mightyscape-1.1-deprecated/extensions/fablabchemnitz/papercraft/openjscad/node_modules/@jscad/openscad-openjscad-translator/dist/web-built.js

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},{}],2:[function(require,module,exports){
(function (global){
/**
 * @license
 * Lodash <https://lodash.com/>
 * Copyright JS Foundation and other contributors <https://js.foundation/>
 * Released under MIT license <https://lodash.com/license>
 * Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE>
 * Copyright Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
 */
;(function() {

  /** Used as a safe reference for `undefined` in pre-ES5 environments. */
  var undefined;

  /** Used as the semantic version number. */
  var VERSION = '4.17.4';

  /** Used as the size to enable large array optimizations. */
  var LARGE_ARRAY_SIZE = 200;

  /** Error message constants. */
  var CORE_ERROR_TEXT = 'Unsupported core-js use. Try https://npms.io/search?q=ponyfill.',
      FUNC_ERROR_TEXT = 'Expected a function';

  /** Used to stand-in for `undefined` hash values. */
  var HASH_UNDEFINED = '__lodash_hash_undefined__';

  /** Used as the maximum memoize cache size. */
  var MAX_MEMOIZE_SIZE = 500;

  /** Used as the internal argument placeholder. */
  var PLACEHOLDER = '__lodash_placeholder__';

  /** Used to compose bitmasks for cloning. */
  var CLONE_DEEP_FLAG = 1,
      CLONE_FLAT_FLAG = 2,
      CLONE_SYMBOLS_FLAG = 4;

  /** Used to compose bitmasks for value comparisons. */
  var COMPARE_PARTIAL_FLAG = 1,
      COMPARE_UNORDERED_FLAG = 2;

  /** Used to compose bitmasks for function metadata. */
  var WRAP_BIND_FLAG = 1,
      WRAP_BIND_KEY_FLAG = 2,
      WRAP_CURRY_BOUND_FLAG = 4,
      WRAP_CURRY_FLAG = 8,
      WRAP_CURRY_RIGHT_FLAG = 16,
      WRAP_PARTIAL_FLAG = 32,
      WRAP_PARTIAL_RIGHT_FLAG = 64,
      WRAP_ARY_FLAG = 128,
      WRAP_REARG_FLAG = 256,
      WRAP_FLIP_FLAG = 512;

  /** Used as default options for `_.truncate`. */
  var DEFAULT_TRUNC_LENGTH = 30,
      DEFAULT_TRUNC_OMISSION = '...';

  /** Used to detect hot functions by number of calls within a span of milliseconds. */
  var HOT_COUNT = 800,
      HOT_SPAN = 16;

  /** Used to indicate the type of lazy iteratees. */
  var LAZY_FILTER_FLAG = 1,
      LAZY_MAP_FLAG = 2,
      LAZY_WHILE_FLAG = 3;

  /** Used as references for various `Number` constants. */
  var INFINITY = 1 / 0,
      MAX_SAFE_INTEGER = 9007199254740991,
      MAX_INTEGER = 1.7976931348623157e+308,
      NAN = 0 / 0;

  /** Used as references for the maximum length and index of an array. */
  var MAX_ARRAY_LENGTH = 4294967295,
      MAX_ARRAY_INDEX = MAX_ARRAY_LENGTH - 1,
      HALF_MAX_ARRAY_LENGTH = MAX_ARRAY_LENGTH >>> 1;

  /** Used to associate wrap methods with their bit flags. */
  var wrapFlags = [
    ['ary', WRAP_ARY_FLAG],
    ['bind', WRAP_BIND_FLAG],
    ['bindKey', WRAP_BIND_KEY_FLAG],
    ['curry', WRAP_CURRY_FLAG],
    ['curryRight', WRAP_CURRY_RIGHT_FLAG],
    ['flip', WRAP_FLIP_FLAG],
    ['partial', WRAP_PARTIAL_FLAG],
    ['partialRight', WRAP_PARTIAL_RIGHT_FLAG],
    ['rearg', WRAP_REARG_FLAG]
  ];

  /** `Object#toString` result references. */
  var argsTag = '[object Arguments]',
      arrayTag = '[object Array]',
      asyncTag = '[object AsyncFunction]',
      boolTag = '[object Boolean]',
      dateTag = '[object Date]',
      domExcTag = '[object DOMException]',
      errorTag = '[object Error]',
      funcTag = '[object Function]',
      genTag = '[object GeneratorFunction]',
      mapTag = '[object Map]',
      numberTag = '[object Number]',
      nullTag = '[object Null]',
      objectTag = '[object Object]',
      promiseTag = '[object Promise]',
      proxyTag = '[object Proxy]',
      regexpTag = '[object RegExp]',
      setTag = '[object Set]',
      stringTag = '[object String]',
      symbolTag = '[object Symbol]',
      undefinedTag = '[object Undefined]',
      weakMapTag = '[object WeakMap]',
      weakSetTag = '[object WeakSet]';

  var arrayBufferTag = '[object ArrayBuffer]',
      dataViewTag = '[object DataView]',
      float32Tag = '[object Float32Array]',
      float64Tag = '[object Float64Array]',
      int8Tag = '[object Int8Array]',
      int16Tag = '[object Int16Array]',
      int32Tag = '[object Int32Array]',
      uint8Tag = '[object Uint8Array]',
      uint8ClampedTag = '[object Uint8ClampedArray]',
      uint16Tag = '[object Uint16Array]',
      uint32Tag = '[object Uint32Array]';

  /** Used to match empty string literals in compiled template source. */
  var reEmptyStringLeading = /\b__p \+= '';/g,
      reEmptyStringMiddle = /\b(__p \+=) '' \+/g,
      reEmptyStringTrailing = /(__e\(.*?\)|\b__t\)) \+\n'';/g;

  /** Used to match HTML entities and HTML characters. */
  var reEscapedHtml = /&(?:amp|lt|gt|quot|#39);/g,
      reUnescapedHtml = /[&<>"']/g,
      reHasEscapedHtml = RegExp(reEscapedHtml.source),
      reHasUnescapedHtml = RegExp(reUnescapedHtml.source);

  /** Used to match template delimiters. */
  var reEscape = /<%-([\s\S]+?)%>/g,
      reEvaluate = /<%([\s\S]+?)%>/g,
      reInterpolate = /<%=([\s\S]+?)%>/g;

  /** Used to match property names within property paths. */
  var reIsDeepProp = /\.|\[(?:[^[\]]*|(["'])(?:(?!\1)[^\\]|\\.)*?\1)\]/,
      reIsPlainProp = /^\w*$/,
      reLeadingDot = /^\./,
      rePropName = /[^.[\]]+|\[(?:(-?\d+(?:\.\d+)?)|(["'])((?:(?!\2)[^\\]|\\.)*?)\2)\]|(?=(?:\.|\[\])(?:\.|\[\]|$))/g;

  /**
   * Used to match `RegExp`
   * [syntax characters](http://ecma-international.org/ecma-262/7.0/#sec-patterns).
   */
  var reRegExpChar = /[\\^$.*+?()[\]{}|]/g,
      reHasRegExpChar = RegExp(reRegExpChar.source);

  /** Used to match leading and trailing whitespace. */
  var reTrim = /^\s+|\s+$/g,
      reTrimStart = /^\s+/,
      reTrimEnd = /\s+$/;

  /** Used to match wrap detail comments. */
  var reWrapComment = /\{(?:\n\/\* \[wrapped with .+\] \*\/)?\n?/,
      reWrapDetails = /\{\n\/\* \[wrapped with (.+)\] \*/,
      reSplitDetails = /,? & /;

  /** Used to match words composed of alphanumeric characters. */
  var reAsciiWord = /[^\x00-\x2f\x3a-\x40\x5b-\x60\x7b-\x7f]+/g;

  /** Used to match backslashes in property paths. */
  var reEscapeChar = /\\(\\)?/g;

  /**
   * Used to match
   * [ES template delimiters](http://ecma-international.org/ecma-262/7.0/#sec-template-literal-lexical-components).
   */
  var reEsTemplate = /\$\{([^\\}]*(?:\\.[^\\}]*)*)\}/g;

  /** Used to match `RegExp` flags from their coerced string values. */
  var reFlags = /\w*$/;

  /** Used to detect bad signed hexadecimal string values. */
  var reIsBadHex = /^[-+]0x[0-9a-f]+$/i;

  /** Used to detect binary string values. */
  var reIsBinary = /^0b[01]+$/i;

  /** Used to detect host constructors (Safari). */
  var reIsHostCtor = /^\[object .+?Constructor\]$/;

  /** Used to detect octal string values. */
  var reIsOctal = /^0o[0-7]+$/i;

  /** Used to detect unsigned integer values. */
  var reIsUint = /^(?:0|[1-9]\d*)$/;

  /** Used to match Latin Unicode letters (excluding mathematical operators). */
  var reLatin = /[\xc0-\xd6\xd8-\xf6\xf8-\xff\u0100-\u017f]/g;

  /** Used to ensure capturing order of template delimiters. */
  var reNoMatch = /($^)/;

  /** Used to match unescaped characters in compiled string literals. */
  var reUnescapedString = /['\n\r\u2028\u2029\\]/g;

  /** Used to compose unicode character classes. */
  var rsAstralRange = '\\ud800-\\udfff',
      rsComboMarksRange = '\\u0300-\\u036f',
      reComboHalfMarksRange = '\\ufe20-\\ufe2f',
      rsComboSymbolsRange = '\\u20d0-\\u20ff',
      rsComboRange = rsComboMarksRange + reComboHalfMarksRange + rsComboSymbolsRange,
      rsDingbatRange = '\\u2700-\\u27bf',
      rsLowerRange = 'a-z\\xdf-\\xf6\\xf8-\\xff',
      rsMathOpRange = '\\xac\\xb1\\xd7\\xf7',
      rsNonCharRange = '\\x00-\\x2f\\x3a-\\x40\\x5b-\\x60\\x7b-\\xbf',
      rsPunctuationRange = '\\u2000-\\u206f',
      rsSpaceRange = ' \\t\\x0b\\f\\xa0\\ufeff\\n\\r\\u2028\\u2029\\u1680\\u180e\\u2000\\u2001\\u2002\\u2003\\u2004\\u2005\\u2006\\u2007\\u2008\\u2009\\u200a\\u202f\\u205f\\u3000',
      rsUpperRange = 'A-Z\\xc0-\\xd6\\xd8-\\xde',
      rsVarRange = '\\ufe0e\\ufe0f',
      rsBreakRange = rsMathOpRange + rsNonCharRange + rsPunctuationRange + rsSpaceRange;

  /** Used to compose unicode capture groups. */
  var rsApos = "['\u2019]",
      rsAstral = '[' + rsAstralRange + ']',
      rsBreak = '[' + rsBreakRange + ']',
      rsCombo = '[' + rsComboRange + ']',
      rsDigits = '\\d+',
      rsDingbat = '[' + rsDingbatRange + ']',
      rsLower = '[' + rsLowerRange + ']',
      rsMisc = '[^' + rsAstralRange + rsBreakRange + rsDigits + rsDingbatRange + rsLowerRange + rsUpperRange + ']',
      rsFitz = '\\ud83c[\\udffb-\\udfff]',
      rsModifier = '(?:' + rsCombo + '|' + rsFitz + ')',
      rsNonAstral = '[^' + rsAstralRange + ']',
      rsRegional = '(?:\\ud83c[\\udde6-\\uddff]){2}',
      rsSurrPair = '[\\ud800-\\udbff][\\udc00-\\udfff]',
      rsUpper = '[' + rsUpperRange + ']',
      rsZWJ = '\\u200d';

  /** Used to compose unicode regexes. */
  var rsMiscLower = '(?:' + rsLower + '|' + rsMisc + ')',
      rsMiscUpper = '(?:' + rsUpper + '|' + rsMisc + ')',
      rsOptContrLower = '(?:' + rsApos + '(?:d|ll|m|re|s|t|ve))?',
      rsOptContrUpper = '(?:' + rsApos + '(?:D|LL|M|RE|S|T|VE))?',
      reOptMod = rsModifier + '?',
      rsOptVar = '[' + rsVarRange + ']?',
      rsOptJoin = '(?:' + rsZWJ + '(?:' + [rsNonAstral, rsRegional, rsSurrPair].join('|') + ')' + rsOptVar + reOptMod + ')*',
      rsOrdLower = '\\d*(?:(?:1st|2nd|3rd|(?![123])\\dth)\\b)',
      rsOrdUpper = '\\d*(?:(?:1ST|2ND|3RD|(?![123])\\dTH)\\b)',
      rsSeq = rsOptVar + reOptMod + rsOptJoin,
      rsEmoji = '(?:' + [rsDingbat, rsRegional, rsSurrPair].join('|') + ')' + rsSeq,
      rsSymbol = '(?:' + [rsNonAstral + rsCombo + '?', rsCombo, rsRegional, rsSurrPair, rsAstral].join('|') + ')';

  /** Used to match apostrophes. */
  var reApos = RegExp(rsApos, 'g');

  /**
   * Used to match [combining diacritical marks](https://en.wikipedia.org/wiki/Combining_Diacritical_Marks) and
   * [combining diacritical marks for symbols](https://en.wikipedia.org/wiki/Combining_Diacritical_Marks_for_Symbols).
   */
  var reComboMark = RegExp(rsCombo, 'g');

  /** Used to match [string symbols](https://mathiasbynens.be/notes/javascript-unicode). */
  var reUnicode = RegExp(rsFitz + '(?=' + rsFitz + ')|' + rsSymbol + rsSeq, 'g');

  /** Used to match complex or compound words. */
  var reUnicodeWord = RegExp([
    rsUpper + '?' + rsLower + '+' + rsOptContrLower + '(?=' + [rsBreak, rsUpper, '$'].join('|') + ')',
    rsMiscUpper + '+' + rsOptContrUpper + '(?=' + [rsBreak, rsUpper + rsMiscLower, '$'].join('|') + ')',
    rsUpper + '?' + rsMiscLower + '+' + rsOptContrLower,
    rsUpper + '+' + rsOptContrUpper,
    rsOrdUpper,
    rsOrdLower,
    rsDigits,
    rsEmoji
  ].join('|'), 'g');

  /** Used to detect strings with [zero-width joiners or code points from the astral planes](http://eev.ee/blog/2015/09/12/dark-corners-of-unicode/). */
  var reHasUnicode = RegExp('[' + rsZWJ + rsAstralRange  + rsComboRange + rsVarRange + ']');

  /** Used to detect strings that need a more robust regexp to match words. */
  var reHasUnicodeWord = /[a-z][A-Z]|[A-Z]{2,}[a-z]|[0-9][a-zA-Z]|[a-zA-Z][0-9]|[^a-zA-Z0-9 ]/;

  /** Used to assign default `context` object properties. */
  var contextProps = [
    'Array', 'Buffer', 'DataView', 'Date', 'Error', 'Float32Array', 'Float64Array',
    'Function', 'Int8Array', 'Int16Array', 'Int32Array', 'Map', 'Math', 'Object',
    'Promise', 'RegExp', 'Set', 'String', 'Symbol', 'TypeError', 'Uint8Array',
    'Uint8ClampedArray', 'Uint16Array', 'Uint32Array', 'WeakMap',
    '_', 'clearTimeout', 'isFinite', 'parseInt', 'setTimeout'
  ];

  /** Used to make template sourceURLs easier to identify. */
  var templateCounter = -1;

  /** Used to identify `toStringTag` values of typed arrays. */
  var typedArrayTags = {};
  typedArrayTags[float32Tag] = typedArrayTags[float64Tag] =
  typedArrayTags[int8Tag] = typedArrayTags[int16Tag] =
  typedArrayTags[int32Tag] = typedArrayTags[uint8Tag] =
  typedArrayTags[uint8ClampedTag] = typedArrayTags[uint16Tag] =
  typedArrayTags[uint32Tag] = true;
  typedArrayTags[argsTag] = typedArrayTags[arrayTag] =
  typedArrayTags[arrayBufferTag] = typedArrayTags[boolTag] =
  typedArrayTags[dataViewTag] = typedArrayTags[dateTag] =
  typedArrayTags[errorTag] = typedArrayTags[funcTag] =
  typedArrayTags[mapTag] = typedArrayTags[numberTag] =
  typedArrayTags[objectTag] = typedArrayTags[regexpTag] =
  typedArrayTags[setTag] = typedArrayTags[stringTag] =
  typedArrayTags[weakMapTag] = false;

  /** Used to identify `toStringTag` values supported by `_.clone`. */
  var cloneableTags = {};
  cloneableTags[argsTag] = cloneableTags[arrayTag] =
  cloneableTags[arrayBufferTag] = cloneableTags[dataViewTag] =
  cloneableTags[boolTag] = cloneableTags[dateTag] =
  cloneableTags[float32Tag] = cloneableTags[float64Tag] =
  cloneableTags[int8Tag] = cloneableTags[int16Tag] =
  cloneableTags[int32Tag] = cloneableTags[mapTag] =
  cloneableTags[numberTag] = cloneableTags[objectTag] =
  cloneableTags[regexpTag] = cloneableTags[setTag] =
  cloneableTags[stringTag] = cloneableTags[symbolTag] =
  cloneableTags[uint8Tag] = cloneableTags[uint8ClampedTag] =
  cloneableTags[uint16Tag] = cloneableTags[uint32Tag] = true;
  cloneableTags[errorTag] = cloneableTags[funcTag] =
  cloneableTags[weakMapTag] = false;

  /** Used to map Latin Unicode letters to basic Latin letters. */
  var deburredLetters = {
    // Latin-1 Supplement block.
    '\xc0': 'A',  '\xc1': 'A', '\xc2': 'A', '\xc3': 'A', '\xc4': 'A', '\xc5': 'A',
    '\xe0': 'a',  '\xe1': 'a', '\xe2': 'a', '\xe3': 'a', '\xe4': 'a', '\xe5': 'a',
    '\xc7': 'C',  '\xe7': 'c',
    '\xd0': 'D',  '\xf0': 'd',
    '\xc8': 'E',  '\xc9': 'E', '\xca': 'E', '\xcb': 'E',
    '\xe8': 'e',  '\xe9': 'e', '\xea': 'e', '\xeb': 'e',
    '\xcc': 'I',  '\xcd': 'I', '\xce': 'I', '\xcf': 'I',
    '\xec': 'i',  '\xed': 'i', '\xee': 'i', '\xef': 'i',
    '\xd1': 'N',  '\xf1': 'n',
    '\xd2': 'O',  '\xd3': 'O', '\xd4': 'O', '\xd5': 'O', '\xd6': 'O', '\xd8': 'O',
    '\xf2': 'o',  '\xf3': 'o', '\xf4': 'o', '\xf5': 'o', '\xf6': 'o', '\xf8': 'o',
    '\xd9': 'U',  '\xda': 'U', '\xdb': 'U', '\xdc': 'U',
    '\xf9': 'u',  '\xfa': 'u', '\xfb': 'u', '\xfc': 'u',
    '\xdd': 'Y',  '\xfd': 'y', '\xff': 'y',
    '\xc6': 'Ae', '\xe6': 'ae',
    '\xde': 'Th', '\xfe': 'th',
    '\xdf': 'ss',
    // Latin Extended-A block.
    '\u0100': 'A',  '\u0102': 'A', '\u0104': 'A',
    '\u0101': 'a',  '\u0103': 'a', '\u0105': 'a',
    '\u0106': 'C',  '\u0108': 'C', '\u010a': 'C', '\u010c': 'C',
    '\u0107': 'c',  '\u0109': 'c', '\u010b': 'c', '\u010d': 'c',
    '\u010e': 'D',  '\u0110': 'D', '\u010f': 'd', '\u0111': 'd',
    '\u0112': 'E',  '\u0114': 'E', '\u0116': 'E', '\u0118': 'E', '\u011a': 'E',
    '\u0113': 'e',  '\u0115': 'e', '\u0117': 'e', '\u0119': 'e', '\u011b': 'e',
    '\u011c': 'G',  '\u011e': 'G', '\u0120': 'G', '\u0122': 'G',
    '\u011d': 'g',  '\u011f': 'g', '\u0121': 'g', '\u0123': 'g',
    '\u0124': 'H',  '\u0126': 'H', '\u0125': 'h', '\u0127': 'h',
    '\u0128': 'I',  '\u012a': 'I', '\u012c': 'I', '\u012e': 'I', '\u0130': 'I',
    '\u0129': 'i',  '\u012b': 'i', '\u012d': 'i', '\u012f': 'i', '\u0131': 'i',
    '\u0134': 'J',  '\u0135': 'j',
    '\u0136': 'K',  '\u0137': 'k', '\u0138': 'k',
    '\u0139': 'L',  '\u013b': 'L', '\u013d': 'L', '\u013f': 'L', '\u0141': 'L',
    '\u013a': 'l',  '\u013c': 'l', '\u013e': 'l', '\u0140': 'l', '\u0142': 'l',
    '\u0143': 'N',  '\u0145': 'N', '\u0147': 'N', '\u014a': 'N',
    '\u0144': 'n',  '\u0146': 'n', '\u0148': 'n', '\u014b': 'n',
    '\u014c': 'O',  '\u014e': 'O', '\u0150': 'O',
    '\u014d': 'o',  '\u014f': 'o', '\u0151': 'o',
    '\u0154': 'R',  '\u0156': 'R', '\u0158': 'R',
    '\u0155': 'r',  '\u0157': 'r', '\u0159': 'r',
    '\u015a': 'S',  '\u015c': 'S', '\u015e': 'S', '\u0160': 'S',
    '\u015b': 's',  '\u015d': 's', '\u015f': 's', '\u0161': 's',
    '\u0162': 'T',  '\u0164': 'T', '\u0166': 'T',
    '\u0163': 't',  '\u0165': 't', '\u0167': 't',
    '\u0168': 'U',  '\u016a': 'U', '\u016c': 'U', '\u016e': 'U', '\u0170': 'U', '\u0172': 'U',
    '\u0169': 'u',  '\u016b': 'u', '\u016d': 'u', '\u016f': 'u', '\u0171': 'u', '\u0173': 'u',
    '\u0174': 'W',  '\u0175': 'w',
    '\u0176': 'Y',  '\u0177': 'y', '\u0178': 'Y',
    '\u0179': 'Z',  '\u017b': 'Z', '\u017d': 'Z',
    '\u017a': 'z',  '\u017c': 'z', '\u017e': 'z',
    '\u0132': 'IJ', '\u0133': 'ij',
    '\u0152': 'Oe', '\u0153': 'oe',
    '\u0149': "'n", '\u017f': 's'
  };

  /** Used to map characters to HTML entities. */
  var htmlEscapes = {
    '&': '&amp;',
    '<': '&lt;',
    '>': '&gt;',
    '"': '&quot;',
    "'": '&#39;'
  };

  /** Used to map HTML entities to characters. */
  var htmlUnescapes = {
    '&amp;': '&',
    '&lt;': '<',
    '&gt;': '>',
    '&quot;': '"',
    '&#39;': "'"
  };

  /** Used to escape characters for inclusion in compiled string literals. */
  var stringEscapes = {
    '\\': '\\',
    "'": "'",
    '\n': 'n',
    '\r': 'r',
    '\u2028': 'u2028',
    '\u2029': 'u2029'
  };

  /** Built-in method references without a dependency on `root`. */
  var freeParseFloat = parseFloat,
      freeParseInt = parseInt;

  /** Detect free variable `global` from Node.js. */
  var freeGlobal = typeof global == 'object' && global && global.Object === Object && global;

  /** Detect free variable `self`. */
  var freeSelf = typeof self == 'object' && self && self.Object === Object && self;

  /** Used as a reference to the global object. */
  var root = freeGlobal || freeSelf || Function('return this')();

  /** Detect free variable `exports`. */
  var freeExports = typeof exports == 'object' && exports && !exports.nodeType && exports;

  /** Detect free variable `module`. */
  var freeModule = freeExports && typeof module == 'object' && module && !module.nodeType && module;

  /** Detect the popular CommonJS extension `module.exports`. */
  var moduleExports = freeModule && freeModule.exports === freeExports;

  /** Detect free variable `process` from Node.js. */
  var freeProcess = moduleExports && freeGlobal.process;

  /** Used to access faster Node.js helpers. */
  var nodeUtil = (function() {
    try {
      return freeProcess && freeProcess.binding && freeProcess.binding('util');
    } catch (e) {}
  }());

  /* Node.js helper references. */
  var nodeIsArrayBuffer = nodeUtil && nodeUtil.isArrayBuffer,
      nodeIsDate = nodeUtil && nodeUtil.isDate,
      nodeIsMap = nodeUtil && nodeUtil.isMap,
      nodeIsRegExp = nodeUtil && nodeUtil.isRegExp,
      nodeIsSet = nodeUtil && nodeUtil.isSet,
      nodeIsTypedArray = nodeUtil && nodeUtil.isTypedArray;

  /*--------------------------------------------------------------------------*/

  /**
   * Adds the key-value `pair` to `map`.
   *
   * @private
   * @param {Object} map The map to modify.
   * @param {Array} pair The key-value pair to add.
   * @returns {Object} Returns `map`.
   */
  function addMapEntry(map, pair) {
    // Don't return `map.set` because it's not chainable in IE 11.
    map.set(pair[0], pair[1]);
    return map;
  }

  /**
   * Adds `value` to `set`.
   *
   * @private
   * @param {Object} set The set to modify.
   * @param {*} value The value to add.
   * @returns {Object} Returns `set`.
   */
  function addSetEntry(set, value) {
    // Don't return `set.add` because it's not chainable in IE 11.
    set.add(value);
    return set;
  }

  /**
   * A faster alternative to `Function#apply`, this function invokes `func`
   * with the `this` binding of `thisArg` and the arguments of `args`.
   *
   * @private
   * @param {Function} func The function to invoke.
   * @param {*} thisArg The `this` binding of `func`.
   * @param {Array} args The arguments to invoke `func` with.
   * @returns {*} Returns the result of `func`.
   */
  function apply(func, thisArg, args) {
    switch (args.length) {
      case 0: return func.call(thisArg);
      case 1: return func.call(thisArg, args[0]);
      case 2: return func.call(thisArg, args[0], args[1]);
      case 3: return func.call(thisArg, args[0], args[1], args[2]);
    }
    return func.apply(thisArg, args);
  }

  /**
   * A specialized version of `baseAggregator` for arrays.
   *
   * @private
   * @param {Array} [array] The array to iterate over.
   * @param {Function} setter The function to set `accumulator` values.
   * @param {Function} iteratee The iteratee to transform keys.
   * @param {Object} accumulator The initial aggregated object.
   * @returns {Function} Returns `accumulator`.
   */
  function arrayAggregator(array, setter, iteratee, accumulator) {
    var index = -1,
        length = array == null ? 0 : array.length;

    while (++index < length) {
      var value = array[index];
      setter(accumulator, value, iteratee(value), array);
    }
    return accumulator;
  }

  /**
   * A specialized version of `_.forEach` for arrays without support for
   * iteratee shorthands.
   *
   * @private
   * @param {Array} [array] The array to iterate over.
   * @param {Function} iteratee The function invoked per iteration.
   * @returns {Array} Returns `array`.
   */
  function arrayEach(array, iteratee) {
    var index = -1,
        length = array == null ? 0 : array.length;

    while (++index < length) {
      if (iteratee(array[index], index, array) === false) {
        break;
      }
    }
    return array;
  }

  /**
   * A specialized version of `_.forEachRight` for arrays without support for
   * iteratee shorthands.
   *
   * @private
   * @param {Array} [array] The array to iterate over.
   * @param {Function} iteratee The function invoked per iteration.
   * @returns {Array} Returns `array`.
   */
  function arrayEachRight(array, iteratee) {
    var length = array == null ? 0 : array.length;

    while (length--) {
      if (iteratee(array[length], length, array) === false) {
        break;
      }
    }
    return array;
  }

  /**
   * A specialized version of `_.every` for arrays without support for
   * iteratee shorthands.
   *
   * @private
   * @param {Array} [array] The array to iterate over.
   * @param {Function} predicate The function invoked per iteration.
   * @returns {boolean} Returns `true` if all elements pass the predicate check,
   *  else `false`.
   */
  function arrayEvery(array, predicate) {
    var index = -1,
        length = array == null ? 0 : array.length;

    while (++index < length) {
      if (!predicate(array[index], index, array)) {
        return false;
      }
    }
    return true;
  }

  /**
   * A specialized version of `_.filter` for arrays without support for
   * iteratee shorthands.
   *
   * @private
   * @param {Array} [array] The array to iterate over.
   * @param {Function} predicate The function invoked per iteration.
   * @returns {Array} Returns the new filtered array.
   */
  function arrayFilter(array, predicate) {
    var index = -1,
        length = array == null ? 0 : array.length,
        resIndex = 0,
        result = [];

    while (++index < length) {
      var value = array[index];
      if (predicate(value, index, array)) {
        result[resIndex++] = value;
      }
    }
    return result;
  }

  /**
   * A specialized version of `_.includes` for arrays without support for
   * specifying an index to search from.
   *
   * @private
   * @param {Array} [array] The array to inspect.
   * @param {*} target The value to search for.
   * @returns {boolean} Returns `true` if `target` is found, else `false`.
   */
  function arrayIncludes(array, value) {
    var length = array == null ? 0 : array.length;
    return !!length && baseIndexOf(array, value, 0) > -1;
  }

  /**
   * This function is like `arrayIncludes` except that it accepts a comparator.
   *
   * @private
   * @param {Array} [array] The array to inspect.
   * @param {*} target The value to search for.
   * @param {Function} comparator The comparator invoked per element.
   * @returns {boolean} Returns `true` if `target` is found, else `false`.
   */
  function arrayIncludesWith(array, value, comparator) {
    var index = -1,
        length = array == null ? 0 : array.length;

    while (++index < length) {
      if (comparator(value, array[index])) {
        return true;
      }
    }
    return false;
  }

  /**
   * A specialized version of `_.map` for arrays without support for iteratee
   * shorthands.
   *
   * @private
   * @param {Array} [array] The array to iterate over.
   * @param {Function} iteratee The function invoked per iteration.
   * @returns {Array} Returns the new mapped array.
   */
  function arrayMap(array, iteratee) {
    var index = -1,
        length = array == null ? 0 : array.length,
        result = Array(length);

    while (++index < length) {
      result[index] = iteratee(array[index], index, array);
    }
    return result;
  }

  /**
   * Appends the elements of `values` to `array`.
   *
   * @private
   * @param {Array} array The array to modify.
   * @param {Array} values The values to append.
   * @returns {Array} Returns `array`.
   */
  function arrayPush(array, values) {
    var index = -1,
        length = values.length,
        offset = array.length;

    while (++index < length) {
      array[offset + index] = values[index];
    }
    return array;
  }

  /**
   * A specialized version of `_.reduce` for arrays without support for
   * iteratee shorthands.
   *
   * @private
   * @param {Array} [array] The array to iterate over.
   * @param {Function} iteratee The function invoked per iteration.
   * @param {*} [accumulator] The initial value.
   * @param {boolean} [initAccum] Specify using the first element of `array` as
   *  the initial value.
   * @returns {*} Returns the accumulated value.
   */
  function arrayReduce(array, iteratee, accumulator, initAccum) {
    var index = -1,
        length = array == null ? 0 : array.length;

    if (initAccum && length) {
      accumulator = array[++index];
    }
    while (++index < length) {
      accumulator = iteratee(accumulator, array[index], index, array);
    }
    return accumulator;
  }

  /**
   * A specialized version of `_.reduceRight` for arrays without support for
   * iteratee shorthands.
   *
   * @private
   * @param {Array} [array] The array to iterate over.
   * @param {Function} iteratee The function invoked per iteration.
   * @param {*} [accumulator] The initial value.
   * @param {boolean} [initAccum] Specify using the last element of `array` as
   *  the initial value.
   * @returns {*} Returns the accumulated value.
   */
  function arrayReduceRight(array, iteratee, accumulator, initAccum) {
    var length = array == null ? 0 : array.length;
    if (initAccum && length) {
      accumulator = array[--length];
    }
    while (length--) {
      accumulator = iteratee(accumulator, array[length], length, array);
    }
    return accumulator;
  }

  /**
   * A specialized version of `_.some` for arrays without support for iteratee
   * shorthands.
   *
   * @private
   * @param {Array} [array] The array to iterate over.
   * @param {Function} predicate The function invoked per iteration.
   * @returns {boolean} Returns `true` if any element passes the predicate check,
   *  else `false`.
   */
  function arraySome(array, predicate) {
    var index = -1,
        length = array == null ? 0 : array.length;

    while (++index < length) {
      if (predicate(array[index], index, array)) {
        return true;
      }
    }
    return false;
  }

  /**
   * Gets the size of an ASCII `string`.
   *
   * @private
   * @param {string} string The string inspect.
   * @returns {number} Returns the string size.
   */
  var asciiSize = baseProperty('length');

  /**
   * Converts an ASCII `string` to an array.
   *
   * @private
   * @param {string} string The string to convert.
   * @returns {Array} Returns the converted array.
   */
  function asciiToArray(string) {
    return string.split('');
  }

  /**
   * Splits an ASCII `string` into an array of its words.
   *
   * @private
   * @param {string} The string to inspect.
   * @returns {Array} Returns the words of `string`.
   */
  function asciiWords(string) {
    return string.match(reAsciiWord) || [];
  }

  /**
   * The base implementation of methods like `_.findKey` and `_.findLastKey`,
   * without support for iteratee shorthands, which iterates over `collection`
   * using `eachFunc`.
   *
   * @private
   * @param {Array|Object} collection The collection to inspect.
   * @param {Function} predicate The function invoked per iteration.
   * @param {Function} eachFunc The function to iterate over `collection`.
   * @returns {*} Returns the found element or its key, else `undefined`.
   */
  function baseFindKey(collection, predicate, eachFunc) {
    var result;
    eachFunc(collection, function(value, key, collection) {
      if (predicate(value, key, collection)) {
        result = key;
        return false;
      }
    });
    return result;
  }

  /**
   * The base implementation of `_.findIndex` and `_.findLastIndex` without
   * support for iteratee shorthands.
   *
   * @private
   * @param {Array} array The array to inspect.
   * @param {Function} predicate The function invoked per iteration.
   * @param {number} fromIndex The index to search from.
   * @param {boolean} [fromRight] Specify iterating from right to left.
   * @returns {number} Returns the index of the matched value, else `-1`.
   */
  function baseFindIndex(array, predicate, fromIndex, fromRight) {
    var length = array.length,
        index = fromIndex + (fromRight ? 1 : -1);

    while ((fromRight ? index-- : ++index < length)) {
      if (predicate(array[index], index, array)) {
        return index;
      }
    }
    return -1;
  }

  /**
   * The base implementation of `_.indexOf` without `fromIndex` bounds checks.
   *
   * @private
   * @param {Array} array The array to inspect.
   * @param {*} value The value to search for.
   * @param {number} fromIndex The index to search from.
   * @returns {number} Returns the index of the matched value, else `-1`.
   */
  function baseIndexOf(array, value, fromIndex) {
    return value === value
      ? strictIndexOf(array, value, fromIndex)
      : baseFindIndex(array, baseIsNaN, fromIndex);
  }

  /**
   * This function is like `baseIndexOf` except that it accepts a comparator.
   *
   * @private
   * @param {Array} array The array to inspect.
   * @param {*} value The value to search for.
   * @param {number} fromIndex The index to search from.
   * @param {Function} comparator The comparator invoked per element.
   * @returns {number} Returns the index of the matched value, else `-1`.
   */
  function baseIndexOfWith(array, value, fromIndex, comparator) {
    var index = fromIndex - 1,
        length = array.length;

    while (++index < length) {
      if (comparator(array[index], value)) {
        return index;
      }
    }
    return -1;
  }

  /**
   * The base implementation of `_.isNaN` without support for number objects.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is `NaN`, else `false`.
   */
  function baseIsNaN(value) {
    return value !== value;
  }

  /**
   * The base implementation of `_.mean` and `_.meanBy` without support for
   * iteratee shorthands.
   *
   * @private
   * @param {Array} array The array to iterate over.
   * @param {Function} iteratee The function invoked per iteration.
   * @returns {number} Returns the mean.
   */
  function baseMean(array, iteratee) {
    var length = array == null ? 0 : array.length;
    return length ? (baseSum(array, iteratee) / length) : NAN;
  }

  /**
   * The base implementation of `_.property` without support for deep paths.
   *
   * @private
   * @param {string} key The key of the property to get.
   * @returns {Function} Returns the new accessor function.
   */
  function baseProperty(key) {
    return function(object) {
      return object == null ? undefined : object[key];
    };
  }

  /**
   * The base implementation of `_.propertyOf` without support for deep paths.
   *
   * @private
   * @param {Object} object The object to query.
   * @returns {Function} Returns the new accessor function.
   */
  function basePropertyOf(object) {
    return function(key) {
      return object == null ? undefined : object[key];
    };
  }

  /**
   * The base implementation of `_.reduce` and `_.reduceRight`, without support
   * for iteratee shorthands, which iterates over `collection` using `eachFunc`.
   *
   * @private
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} iteratee The function invoked per iteration.
   * @param {*} accumulator The initial value.
   * @param {boolean} initAccum Specify using the first or last element of
   *  `collection` as the initial value.
   * @param {Function} eachFunc The function to iterate over `collection`.
   * @returns {*} Returns the accumulated value.
   */
  function baseReduce(collection, iteratee, accumulator, initAccum, eachFunc) {
    eachFunc(collection, function(value, index, collection) {
      accumulator = initAccum
        ? (initAccum = false, value)
        : iteratee(accumulator, value, index, collection);
    });
    return accumulator;
  }

  /**
   * The base implementation of `_.sortBy` which uses `comparer` to define the
   * sort order of `array` and replaces criteria objects with their corresponding
   * values.
   *
   * @private
   * @param {Array} array The array to sort.
   * @param {Function} comparer The function to define sort order.
   * @returns {Array} Returns `array`.
   */
  function baseSortBy(array, comparer) {
    var length = array.length;

    array.sort(comparer);
    while (length--) {
      array[length] = array[length].value;
    }
    return array;
  }

  /**
   * The base implementation of `_.sum` and `_.sumBy` without support for
   * iteratee shorthands.
   *
   * @private
   * @param {Array} array The array to iterate over.
   * @param {Function} iteratee The function invoked per iteration.
   * @returns {number} Returns the sum.
   */
  function baseSum(array, iteratee) {
    var result,
        index = -1,
        length = array.length;

    while (++index < length) {
      var current = iteratee(array[index]);
      if (current !== undefined) {
        result = result === undefined ? current : (result + current);
      }
    }
    return result;
  }

  /**
   * The base implementation of `_.times` without support for iteratee shorthands
   * or max array length checks.
   *
   * @private
   * @param {number} n The number of times to invoke `iteratee`.
   * @param {Function} iteratee The function invoked per iteration.
   * @returns {Array} Returns the array of results.
   */
  function baseTimes(n, iteratee) {
    var index = -1,
        result = Array(n);

    while (++index < n) {
      result[index] = iteratee(index);
    }
    return result;
  }

  /**
   * The base implementation of `_.toPairs` and `_.toPairsIn` which creates an array
   * of key-value pairs for `object` corresponding to the property names of `props`.
   *
   * @private
   * @param {Object} object The object to query.
   * @param {Array} props The property names to get values for.
   * @returns {Object} Returns the key-value pairs.
   */
  function baseToPairs(object, props) {
    return arrayMap(props, function(key) {
      return [key, object[key]];
    });
  }

  /**
   * The base implementation of `_.unary` without support for storing metadata.
   *
   * @private
   * @param {Function} func The function to cap arguments for.
   * @returns {Function} Returns the new capped function.
   */
  function baseUnary(func) {
    return function(value) {
      return func(value);
    };
  }

  /**
   * The base implementation of `_.values` and `_.valuesIn` which creates an
   * array of `object` property values corresponding to the property names
   * of `props`.
   *
   * @private
   * @param {Object} object The object to query.
   * @param {Array} props The property names to get values for.
   * @returns {Object} Returns the array of property values.
   */
  function baseValues(object, props) {
    return arrayMap(props, function(key) {
      return object[key];
    });
  }

  /**
   * Checks if a `cache` value for `key` exists.
   *
   * @private
   * @param {Object} cache The cache to query.
   * @param {string} key The key of the entry to check.
   * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
   */
  function cacheHas(cache, key) {
    return cache.has(key);
  }

  /**
   * Used by `_.trim` and `_.trimStart` to get the index of the first string symbol
   * that is not found in the character symbols.
   *
   * @private
   * @param {Array} strSymbols The string symbols to inspect.
   * @param {Array} chrSymbols The character symbols to find.
   * @returns {number} Returns the index of the first unmatched string symbol.
   */
  function charsStartIndex(strSymbols, chrSymbols) {
    var index = -1,
        length = strSymbols.length;

    while (++index < length && baseIndexOf(chrSymbols, strSymbols[index], 0) > -1) {}
    return index;
  }

  /**
   * Used by `_.trim` and `_.trimEnd` to get the index of the last string symbol
   * that is not found in the character symbols.
   *
   * @private
   * @param {Array} strSymbols The string symbols to inspect.
   * @param {Array} chrSymbols The character symbols to find.
   * @returns {number} Returns the index of the last unmatched string symbol.
   */
  function charsEndIndex(strSymbols, chrSymbols) {
    var index = strSymbols.length;

    while (index-- && baseIndexOf(chrSymbols, strSymbols[index], 0) > -1) {}
    return index;
  }

  /**
   * Gets the number of `placeholder` occurrences in `array`.
   *
   * @private
   * @param {Array} array The array to inspect.
   * @param {*} placeholder The placeholder to search for.
   * @returns {number} Returns the placeholder count.
   */
  function countHolders(array, placeholder) {
    var length = array.length,
        result = 0;

    while (length--) {
      if (array[length] === placeholder) {
        ++result;
      }
    }
    return result;
  }

  /**
   * Used by `_.deburr` to convert Latin-1 Supplement and Latin Extended-A
   * letters to basic Latin letters.
   *
   * @private
   * @param {string} letter The matched letter to deburr.
   * @returns {string} Returns the deburred letter.
   */
  var deburrLetter = basePropertyOf(deburredLetters);

  /**
   * Used by `_.escape` to convert characters to HTML entities.
   *
   * @private
   * @param {string} chr The matched character to escape.
   * @returns {string} Returns the escaped character.
   */
  var escapeHtmlChar = basePropertyOf(htmlEscapes);

  /**
   * Used by `_.template` to escape characters for inclusion in compiled string literals.
   *
   * @private
   * @param {string} chr The matched character to escape.
   * @returns {string} Returns the escaped character.
   */
  function escapeStringChar(chr) {
    return '\\' + stringEscapes[chr];
  }

  /**
   * Gets the value at `key` of `object`.
   *
   * @private
   * @param {Object} [object] The object to query.
   * @param {string} key The key of the property to get.
   * @returns {*} Returns the property value.
   */
  function getValue(object, key) {
    return object == null ? undefined : object[key];
  }

  /**
   * Checks if `string` contains Unicode symbols.
   *
   * @private
   * @param {string} string The string to inspect.
   * @returns {boolean} Returns `true` if a symbol is found, else `false`.
   */
  function hasUnicode(string) {
    return reHasUnicode.test(string);
  }

  /**
   * Checks if `string` contains a word composed of Unicode symbols.
   *
   * @private
   * @param {string} string The string to inspect.
   * @returns {boolean} Returns `true` if a word is found, else `false`.
   */
  function hasUnicodeWord(string) {
    return reHasUnicodeWord.test(string);
  }

  /**
   * Converts `iterator` to an array.
   *
   * @private
   * @param {Object} iterator The iterator to convert.
   * @returns {Array} Returns the converted array.
   */
  function iteratorToArray(iterator) {
    var data,
        result = [];

    while (!(data = iterator.next()).done) {
      result.push(data.value);
    }
    return result;
  }

  /**
   * Converts `map` to its key-value pairs.
   *
   * @private
   * @param {Object} map The map to convert.
   * @returns {Array} Returns the key-value pairs.
   */
  function mapToArray(map) {
    var index = -1,
        result = Array(map.size);

    map.forEach(function(value, key) {
      result[++index] = [key, value];
    });
    return result;
  }

  /**
   * Creates a unary function that invokes `func` with its argument transformed.
   *
   * @private
   * @param {Function} func The function to wrap.
   * @param {Function} transform The argument transform.
   * @returns {Function} Returns the new function.
   */
  function overArg(func, transform) {
    return function(arg) {
      return func(transform(arg));
    };
  }

  /**
   * Replaces all `placeholder` elements in `array` with an internal placeholder
   * and returns an array of their indexes.
   *
   * @private
   * @param {Array} array The array to modify.
   * @param {*} placeholder The placeholder to replace.
   * @returns {Array} Returns the new array of placeholder indexes.
   */
  function replaceHolders(array, placeholder) {
    var index = -1,
        length = array.length,
        resIndex = 0,
        result = [];

    while (++index < length) {
      var value = array[index];
      if (value === placeholder || value === PLACEHOLDER) {
        array[index] = PLACEHOLDER;
        result[resIndex++] = index;
      }
    }
    return result;
  }

  /**
   * Converts `set` to an array of its values.
   *
   * @private
   * @param {Object} set The set to convert.
   * @returns {Array} Returns the values.
   */
  function setToArray(set) {
    var index = -1,
        result = Array(set.size);

    set.forEach(function(value) {
      result[++index] = value;
    });
    return result;
  }

  /**
   * Converts `set` to its value-value pairs.
   *
   * @private
   * @param {Object} set The set to convert.
   * @returns {Array} Returns the value-value pairs.
   */
  function setToPairs(set) {
    var index = -1,
        result = Array(set.size);

    set.forEach(function(value) {
      result[++index] = [value, value];
    });
    return result;
  }

  /**
   * A specialized version of `_.indexOf` which performs strict equality
   * comparisons of values, i.e. `===`.
   *
   * @private
   * @param {Array} array The array to inspect.
   * @param {*} value The value to search for.
   * @param {number} fromIndex The index to search from.
   * @returns {number} Returns the index of the matched value, else `-1`.
   */
  function strictIndexOf(array, value, fromIndex) {
    var index = fromIndex - 1,
        length = array.length;

    while (++index < length) {
      if (array[index] === value) {
        return index;
      }
    }
    return -1;
  }

  /**
   * A specialized version of `_.lastIndexOf` which performs strict equality
   * comparisons of values, i.e. `===`.
   *
   * @private
   * @param {Array} array The array to inspect.
   * @param {*} value The value to search for.
   * @param {number} fromIndex The index to search from.
   * @returns {number} Returns the index of the matched value, else `-1`.
   */
  function strictLastIndexOf(array, value, fromIndex) {
    var index = fromIndex + 1;
    while (index--) {
      if (array[index] === value) {
        return index;
      }
    }
    return index;
  }

  /**
   * Gets the number of symbols in `string`.
   *
   * @private
   * @param {string} string The string to inspect.
   * @returns {number} Returns the string size.
   */
  function stringSize(string) {
    return hasUnicode(string)
      ? unicodeSize(string)
      : asciiSize(string);
  }

  /**
   * Converts `string` to an array.
   *
   * @private
   * @param {string} string The string to convert.
   * @returns {Array} Returns the converted array.
   */
  function stringToArray(string) {
    return hasUnicode(string)
      ? unicodeToArray(string)
      : asciiToArray(string);
  }

  /**
   * Used by `_.unescape` to convert HTML entities to characters.
   *
   * @private
   * @param {string} chr The matched character to unescape.
   * @returns {string} Returns the unescaped character.
   */
  var unescapeHtmlChar = basePropertyOf(htmlUnescapes);

  /**
   * Gets the size of a Unicode `string`.
   *
   * @private
   * @param {string} string The string inspect.
   * @returns {number} Returns the string size.
   */
  function unicodeSize(string) {
    var result = reUnicode.lastIndex = 0;
    while (reUnicode.test(string)) {
      ++result;
    }
    return result;
  }

  /**
   * Converts a Unicode `string` to an array.
   *
   * @private
   * @param {string} string The string to convert.
   * @returns {Array} Returns the converted array.
   */
  function unicodeToArray(string) {
    return string.match(reUnicode) || [];
  }

  /**
   * Splits a Unicode `string` into an array of its words.
   *
   * @private
   * @param {string} The string to inspect.
   * @returns {Array} Returns the words of `string`.
   */
  function unicodeWords(string) {
    return string.match(reUnicodeWord) || [];
  }

  /*--------------------------------------------------------------------------*/

  /**
   * Create a new pristine `lodash` function using the `context` object.
   *
   * @static
   * @memberOf _
   * @since 1.1.0
   * @category Util
   * @param {Object} [context=root] The context object.
   * @returns {Function} Returns a new `lodash` function.
   * @example
   *
   * _.mixin({ 'foo': _.constant('foo') });
   *
   * var lodash = _.runInContext();
   * lodash.mixin({ 'bar': lodash.constant('bar') });
   *
   * _.isFunction(_.foo);
   * // => true
   * _.isFunction(_.bar);
   * // => false
   *
   * lodash.isFunction(lodash.foo);
   * // => false
   * lodash.isFunction(lodash.bar);
   * // => true
   *
   * // Create a suped-up `defer` in Node.js.
   * var defer = _.runInContext({ 'setTimeout': setImmediate }).defer;
   */
  var runInContext = (function runInContext(context) {
    context = context == null ? root : _.defaults(root.Object(), context, _.pick(root, contextProps));

    /** Built-in constructor references. */
    var Array = context.Array,
        Date = context.Date,
        Error = context.Error,
        Function = context.Function,
        Math = context.Math,
        Object = context.Object,
        RegExp = context.RegExp,
        String = context.String,
        TypeError = context.TypeError;

    /** Used for built-in method references. */
    var arrayProto = Array.prototype,
        funcProto = Function.prototype,
        objectProto = Object.prototype;

    /** Used to detect overreaching core-js shims. */
    var coreJsData = context['__core-js_shared__'];

    /** Used to resolve the decompiled source of functions. */
    var funcToString = funcProto.toString;

    /** Used to check objects for own properties. */
    var hasOwnProperty = objectProto.hasOwnProperty;

    /** Used to generate unique IDs. */
    var idCounter = 0;

    /** Used to detect methods masquerading as native. */
    var maskSrcKey = (function() {
      var uid = /[^.]+$/.exec(coreJsData && coreJsData.keys && coreJsData.keys.IE_PROTO || '');
      return uid ? ('Symbol(src)_1.' + uid) : '';
    }());

    /**
     * Used to resolve the
     * [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring)
     * of values.
     */
    var nativeObjectToString = objectProto.toString;

    /** Used to infer the `Object` constructor. */
    var objectCtorString = funcToString.call(Object);

    /** Used to restore the original `_` reference in `_.noConflict`. */
    var oldDash = root._;

    /** Used to detect if a method is native. */
    var reIsNative = RegExp('^' +
      funcToString.call(hasOwnProperty).replace(reRegExpChar, '\\$&')
      .replace(/hasOwnProperty|(function).*?(?=\\\()| for .+?(?=\\\])/g, '$1.*?') + '$'
    );

    /** Built-in value references. */
    var Buffer = moduleExports ? context.Buffer : undefined,
        Symbol = context.Symbol,
        Uint8Array = context.Uint8Array,
        allocUnsafe = Buffer ? Buffer.allocUnsafe : undefined,
        getPrototype = overArg(Object.getPrototypeOf, Object),
        objectCreate = Object.create,
        propertyIsEnumerable = objectProto.propertyIsEnumerable,
        splice = arrayProto.splice,
        spreadableSymbol = Symbol ? Symbol.isConcatSpreadable : undefined,
        symIterator = Symbol ? Symbol.iterator : undefined,
        symToStringTag = Symbol ? Symbol.toStringTag : undefined;

    var defineProperty = (function() {
      try {
        var func = getNative(Object, 'defineProperty');
        func({}, '', {});
        return func;
      } catch (e) {}
    }());

    /** Mocked built-ins. */
    var ctxClearTimeout = context.clearTimeout !== root.clearTimeout && context.clearTimeout,
        ctxNow = Date && Date.now !== root.Date.now && Date.now,
        ctxSetTimeout = context.setTimeout !== root.setTimeout && context.setTimeout;

    /* Built-in method references for those with the same name as other `lodash` methods. */
    var nativeCeil = Math.ceil,
        nativeFloor = Math.floor,
        nativeGetSymbols = Object.getOwnPropertySymbols,
        nativeIsBuffer = Buffer ? Buffer.isBuffer : undefined,
        nativeIsFinite = context.isFinite,
        nativeJoin = arrayProto.join,
        nativeKeys = overArg(Object.keys, Object),
        nativeMax = Math.max,
        nativeMin = Math.min,
        nativeNow = Date.now,
        nativeParseInt = context.parseInt,
        nativeRandom = Math.random,
        nativeReverse = arrayProto.reverse;

    /* Built-in method references that are verified to be native. */
    var DataView = getNative(context, 'DataView'),
        Map = getNative(context, 'Map'),
        Promise = getNative(context, 'Promise'),
        Set = getNative(context, 'Set'),
        WeakMap = getNative(context, 'WeakMap'),
        nativeCreate = getNative(Object, 'create');

    /** Used to store function metadata. */
    var metaMap = WeakMap && new WeakMap;

    /** Used to lookup unminified function names. */
    var realNames = {};

    /** Used to detect maps, sets, and weakmaps. */
    var dataViewCtorString = toSource(DataView),
        mapCtorString = toSource(Map),
        promiseCtorString = toSource(Promise),
        setCtorString = toSource(Set),
        weakMapCtorString = toSource(WeakMap);

    /** Used to convert symbols to primitives and strings. */
    var symbolProto = Symbol ? Symbol.prototype : undefined,
        symbolValueOf = symbolProto ? symbolProto.valueOf : undefined,
        symbolToString = symbolProto ? symbolProto.toString : undefined;

    /*------------------------------------------------------------------------*/

    /**
     * Creates a `lodash` object which wraps `value` to enable implicit method
     * chain sequences. Methods that operate on and return arrays, collections,
     * and functions can be chained together. Methods that retrieve a single value
     * or may return a primitive value will automatically end the chain sequence
     * and return the unwrapped value. Otherwise, the value must be unwrapped
     * with `_#value`.
     *
     * Explicit chain sequences, which must be unwrapped with `_#value`, may be
     * enabled using `_.chain`.
     *
     * The execution of chained methods is lazy, that is, it's deferred until
     * `_#value` is implicitly or explicitly called.
     *
     * Lazy evaluation allows several methods to support shortcut fusion.
     * Shortcut fusion is an optimization to merge iteratee calls; this avoids
     * the creation of intermediate arrays and can greatly reduce the number of
     * iteratee executions. Sections of a chain sequence qualify for shortcut
     * fusion if the section is applied to an array and iteratees accept only
     * one argument. The heuristic for whether a section qualifies for shortcut
     * fusion is subject to change.
     *
     * Chaining is supported in custom builds as long as the `_#value` method is
     * directly or indirectly included in the build.
     *
     * In addition to lodash methods, wrappers have `Array` and `String` methods.
     *
     * The wrapper `Array` methods are:
     * `concat`, `join`, `pop`, `push`, `shift`, `sort`, `splice`, and `unshift`
     *
     * The wrapper `String` methods are:
     * `replace` and `split`
     *
     * The wrapper methods that support shortcut fusion are:
     * `at`, `compact`, `drop`, `dropRight`, `dropWhile`, `filter`, `find`,
     * `findLast`, `head`, `initial`, `last`, `map`, `reject`, `reverse`, `slice`,
     * `tail`, `take`, `takeRight`, `takeRightWhile`, `takeWhile`, and `toArray`
     *
     * The chainable wrapper methods are:
     * `after`, `ary`, `assign`, `assignIn`, `assignInWith`, `assignWith`, `at`,
     * `before`, `bind`, `bindAll`, `bindKey`, `castArray`, `chain`, `chunk`,
     * `commit`, `compact`, `concat`, `conforms`, `constant`, `countBy`, `create`,
     * `curry`, `debounce`, `defaults`, `defaultsDeep`, `defer`, `delay`,
     * `difference`, `differenceBy`, `differenceWith`, `drop`, `dropRight`,
     * `dropRightWhile`, `dropWhile`, `extend`, `extendWith`, `fill`, `filter`,
     * `flatMap`, `flatMapDeep`, `flatMapDepth`, `flatten`, `flattenDeep`,
     * `flattenDepth`, `flip`, `flow`, `flowRight`, `fromPairs`, `functions`,
     * `functionsIn`, `groupBy`, `initial`, `intersection`, `intersectionBy`,
     * `intersectionWith`, `invert`, `invertBy`, `invokeMap`, `iteratee`, `keyBy`,
     * `keys`, `keysIn`, `map`, `mapKeys`, `mapValues`, `matches`, `matchesProperty`,
     * `memoize`, `merge`, `mergeWith`, `method`, `methodOf`, `mixin`, `negate`,
     * `nthArg`, `omit`, `omitBy`, `once`, `orderBy`, `over`, `overArgs`,
     * `overEvery`, `overSome`, `partial`, `partialRight`, `partition`, `pick`,
     * `pickBy`, `plant`, `property`, `propertyOf`, `pull`, `pullAll`, `pullAllBy`,
     * `pullAllWith`, `pullAt`, `push`, `range`, `rangeRight`, `rearg`, `reject`,
     * `remove`, `rest`, `reverse`, `sampleSize`, `set`, `setWith`, `shuffle`,
     * `slice`, `sort`, `sortBy`, `splice`, `spread`, `tail`, `take`, `takeRight`,
     * `takeRightWhile`, `takeWhile`, `tap`, `throttle`, `thru`, `toArray`,
     * `toPairs`, `toPairsIn`, `toPath`, `toPlainObject`, `transform`, `unary`,
     * `union`, `unionBy`, `unionWith`, `uniq`, `uniqBy`, `uniqWith`, `unset`,
     * `unshift`, `unzip`, `unzipWith`, `update`, `updateWith`, `values`,
     * `valuesIn`, `without`, `wrap`, `xor`, `xorBy`, `xorWith`, `zip`,
     * `zipObject`, `zipObjectDeep`, and `zipWith`
     *
     * The wrapper methods that are **not** chainable by default are:
     * `add`, `attempt`, `camelCase`, `capitalize`, `ceil`, `clamp`, `clone`,
     * `cloneDeep`, `cloneDeepWith`, `cloneWith`, `conformsTo`, `deburr`,
     * `defaultTo`, `divide`, `each`, `eachRight`, `endsWith`, `eq`, `escape`,
     * `escapeRegExp`, `every`, `find`, `findIndex`, `findKey`, `findLast`,
     * `findLastIndex`, `findLastKey`, `first`, `floor`, `forEach`, `forEachRight`,
     * `forIn`, `forInRight`, `forOwn`, `forOwnRight`, `get`, `gt`, `gte`, `has`,
     * `hasIn`, `head`, `identity`, `includes`, `indexOf`, `inRange`, `invoke`,
     * `isArguments`, `isArray`, `isArrayBuffer`, `isArrayLike`, `isArrayLikeObject`,
     * `isBoolean`, `isBuffer`, `isDate`, `isElement`, `isEmpty`, `isEqual`,
     * `isEqualWith`, `isError`, `isFinite`, `isFunction`, `isInteger`, `isLength`,
     * `isMap`, `isMatch`, `isMatchWith`, `isNaN`, `isNative`, `isNil`, `isNull`,
     * `isNumber`, `isObject`, `isObjectLike`, `isPlainObject`, `isRegExp`,
     * `isSafeInteger`, `isSet`, `isString`, `isUndefined`, `isTypedArray`,
     * `isWeakMap`, `isWeakSet`, `join`, `kebabCase`, `last`, `lastIndexOf`,
     * `lowerCase`, `lowerFirst`, `lt`, `lte`, `max`, `maxBy`, `mean`, `meanBy`,
     * `min`, `minBy`, `multiply`, `noConflict`, `noop`, `now`, `nth`, `pad`,
     * `padEnd`, `padStart`, `parseInt`, `pop`, `random`, `reduce`, `reduceRight`,
     * `repeat`, `result`, `round`, `runInContext`, `sample`, `shift`, `size`,
     * `snakeCase`, `some`, `sortedIndex`, `sortedIndexBy`, `sortedLastIndex`,
     * `sortedLastIndexBy`, `startCase`, `startsWith`, `stubArray`, `stubFalse`,
     * `stubObject`, `stubString`, `stubTrue`, `subtract`, `sum`, `sumBy`,
     * `template`, `times`, `toFinite`, `toInteger`, `toJSON`, `toLength`,
     * `toLower`, `toNumber`, `toSafeInteger`, `toString`, `toUpper`, `trim`,
     * `trimEnd`, `trimStart`, `truncate`, `unescape`, `uniqueId`, `upperCase`,
     * `upperFirst`, `value`, and `words`
     *
     * @name _
     * @constructor
     * @category Seq
     * @param {*} value The value to wrap in a `lodash` instance.
     * @returns {Object} Returns the new `lodash` wrapper instance.
     * @example
     *
     * function square(n) {
     *   return n * n;
     * }
     *
     * var wrapped = _([1, 2, 3]);
     *
     * // Returns an unwrapped value.
     * wrapped.reduce(_.add);
     * // => 6
     *
     * // Returns a wrapped value.
     * var squares = wrapped.map(square);
     *
     * _.isArray(squares);
     * // => false
     *
     * _.isArray(squares.value());
     * // => true
     */
    function lodash(value) {
      if (isObjectLike(value) && !isArray(value) && !(value instanceof LazyWrapper)) {
        if (value instanceof LodashWrapper) {
          return value;
        }
        if (hasOwnProperty.call(value, '__wrapped__')) {
          return wrapperClone(value);
        }
      }
      return new LodashWrapper(value);
    }

    /**
     * The base implementation of `_.create` without support for assigning
     * properties to the created object.
     *
     * @private
     * @param {Object} proto The object to inherit from.
     * @returns {Object} Returns the new object.
     */
    var baseCreate = (function() {
      function object() {}
      return function(proto) {
        if (!isObject(proto)) {
          return {};
        }
        if (objectCreate) {
          return objectCreate(proto);
        }
        object.prototype = proto;
        var result = new object;
        object.prototype = undefined;
        return result;
      };
    }());

    /**
     * The function whose prototype chain sequence wrappers inherit from.
     *
     * @private
     */
    function baseLodash() {
      // No operation performed.
    }

    /**
     * The base constructor for creating `lodash` wrapper objects.
     *
     * @private
     * @param {*} value The value to wrap.
     * @param {boolean} [chainAll] Enable explicit method chain sequences.
     */
    function LodashWrapper(value, chainAll) {
      this.__wrapped__ = value;
      this.__actions__ = [];
      this.__chain__ = !!chainAll;
      this.__index__ = 0;
      this.__values__ = undefined;
    }

    /**
     * By default, the template delimiters used by lodash are like those in
     * embedded Ruby (ERB) as well as ES2015 template strings. Change the
     * following template settings to use alternative delimiters.
     *
     * @static
     * @memberOf _
     * @type {Object}
     */
    lodash.templateSettings = {

      /**
       * Used to detect `data` property values to be HTML-escaped.
       *
       * @memberOf _.templateSettings
       * @type {RegExp}
       */
      'escape': reEscape,

      /**
       * Used to detect code to be evaluated.
       *
       * @memberOf _.templateSettings
       * @type {RegExp}
       */
      'evaluate': reEvaluate,

      /**
       * Used to detect `data` property values to inject.
       *
       * @memberOf _.templateSettings
       * @type {RegExp}
       */
      'interpolate': reInterpolate,

      /**
       * Used to reference the data object in the template text.
       *
       * @memberOf _.templateSettings
       * @type {string}
       */
      'variable': '',

      /**
       * Used to import variables into the compiled template.
       *
       * @memberOf _.templateSettings
       * @type {Object}
       */
      'imports': {

        /**
         * A reference to the `lodash` function.
         *
         * @memberOf _.templateSettings.imports
         * @type {Function}
         */
        '_': lodash
      }
    };

    // Ensure wrappers are instances of `baseLodash`.
    lodash.prototype = baseLodash.prototype;
    lodash.prototype.constructor = lodash;

    LodashWrapper.prototype = baseCreate(baseLodash.prototype);
    LodashWrapper.prototype.constructor = LodashWrapper;

    /*------------------------------------------------------------------------*/

    /**
     * Creates a lazy wrapper object which wraps `value` to enable lazy evaluation.
     *
     * @private
     * @constructor
     * @param {*} value The value to wrap.
     */
    function LazyWrapper(value) {
      this.__wrapped__ = value;
      this.__actions__ = [];
      this.__dir__ = 1;
      this.__filtered__ = false;
      this.__iteratees__ = [];
      this.__takeCount__ = MAX_ARRAY_LENGTH;
      this.__views__ = [];
    }

    /**
     * Creates a clone of the lazy wrapper object.
     *
     * @private
     * @name clone
     * @memberOf LazyWrapper
     * @returns {Object} Returns the cloned `LazyWrapper` object.
     */
    function lazyClone() {
      var result = new LazyWrapper(this.__wrapped__);
      result.__actions__ = copyArray(this.__actions__);
      result.__dir__ = this.__dir__;
      result.__filtered__ = this.__filtered__;
      result.__iteratees__ = copyArray(this.__iteratees__);
      result.__takeCount__ = this.__takeCount__;
      result.__views__ = copyArray(this.__views__);
      return result;
    }

    /**
     * Reverses the direction of lazy iteration.
     *
     * @private
     * @name reverse
     * @memberOf LazyWrapper
     * @returns {Object} Returns the new reversed `LazyWrapper` object.
     */
    function lazyReverse() {
      if (this.__filtered__) {
        var result = new LazyWrapper(this);
        result.__dir__ = -1;
        result.__filtered__ = true;
      } else {
        result = this.clone();
        result.__dir__ *= -1;
      }
      return result;
    }

    /**
     * Extracts the unwrapped value from its lazy wrapper.
     *
     * @private
     * @name value
     * @memberOf LazyWrapper
     * @returns {*} Returns the unwrapped value.
     */
    function lazyValue() {
      var array = this.__wrapped__.value(),
          dir = this.__dir__,
          isArr = isArray(array),
          isRight = dir < 0,
          arrLength = isArr ? array.length : 0,
          view = getView(0, arrLength, this.__views__),
          start = view.start,
          end = view.end,
          length = end - start,
          index = isRight ? end : (start - 1),
          iteratees = this.__iteratees__,
          iterLength = iteratees.length,
          resIndex = 0,
          takeCount = nativeMin(length, this.__takeCount__);

      if (!isArr || (!isRight && arrLength == length && takeCount == length)) {
        return baseWrapperValue(array, this.__actions__);
      }
      var result = [];

      outer:
      while (length-- && resIndex < takeCount) {
        index += dir;

        var iterIndex = -1,
            value = array[index];

        while (++iterIndex < iterLength) {
          var data = iteratees[iterIndex],
              iteratee = data.iteratee,
              type = data.type,
              computed = iteratee(value);

          if (type == LAZY_MAP_FLAG) {
            value = computed;
          } else if (!computed) {
            if (type == LAZY_FILTER_FLAG) {
              continue outer;
            } else {
              break outer;
            }
          }
        }
        result[resIndex++] = value;
      }
      return result;
    }

    // Ensure `LazyWrapper` is an instance of `baseLodash`.
    LazyWrapper.prototype = baseCreate(baseLodash.prototype);
    LazyWrapper.prototype.constructor = LazyWrapper;

    /*------------------------------------------------------------------------*/

    /**
     * Creates a hash object.
     *
     * @private
     * @constructor
     * @param {Array} [entries] The key-value pairs to cache.
     */
    function Hash(entries) {
      var index = -1,
          length = entries == null ? 0 : entries.length;

      this.clear();
      while (++index < length) {
        var entry = entries[index];
        this.set(entry[0], entry[1]);
      }
    }

    /**
     * Removes all key-value entries from the hash.
     *
     * @private
     * @name clear
     * @memberOf Hash
     */
    function hashClear() {
      this.__data__ = nativeCreate ? nativeCreate(null) : {};
      this.size = 0;
    }

    /**
     * Removes `key` and its value from the hash.
     *
     * @private
     * @name delete
     * @memberOf Hash
     * @param {Object} hash The hash to modify.
     * @param {string} key The key of the value to remove.
     * @returns {boolean} Returns `true` if the entry was removed, else `false`.
     */
    function hashDelete(key) {
      var result = this.has(key) && delete this.__data__[key];
      this.size -= result ? 1 : 0;
      return result;
    }

    /**
     * Gets the hash value for `key`.
     *
     * @private
     * @name get
     * @memberOf Hash
     * @param {string} key The key of the value to get.
     * @returns {*} Returns the entry value.
     */
    function hashGet(key) {
      var data = this.__data__;
      if (nativeCreate) {
        var result = data[key];
        return result === HASH_UNDEFINED ? undefined : result;
      }
      return hasOwnProperty.call(data, key) ? data[key] : undefined;
    }

    /**
     * Checks if a hash value for `key` exists.
     *
     * @private
     * @name has
     * @memberOf Hash
     * @param {string} key The key of the entry to check.
     * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
     */
    function hashHas(key) {
      var data = this.__data__;
      return nativeCreate ? (data[key] !== undefined) : hasOwnProperty.call(data, key);
    }

    /**
     * Sets the hash `key` to `value`.
     *
     * @private
     * @name set
     * @memberOf Hash
     * @param {string} key The key of the value to set.
     * @param {*} value The value to set.
     * @returns {Object} Returns the hash instance.
     */
    function hashSet(key, value) {
      var data = this.__data__;
      this.size += this.has(key) ? 0 : 1;
      data[key] = (nativeCreate && value === undefined) ? HASH_UNDEFINED : value;
      return this;
    }

    // Add methods to `Hash`.
    Hash.prototype.clear = hashClear;
    Hash.prototype['delete'] = hashDelete;
    Hash.prototype.get = hashGet;
    Hash.prototype.has = hashHas;
    Hash.prototype.set = hashSet;

    /*------------------------------------------------------------------------*/

    /**
     * Creates an list cache object.
     *
     * @private
     * @constructor
     * @param {Array} [entries] The key-value pairs to cache.
     */
    function ListCache(entries) {
      var index = -1,
          length = entries == null ? 0 : entries.length;

      this.clear();
      while (++index < length) {
        var entry = entries[index];
        this.set(entry[0], entry[1]);
      }
    }

    /**
     * Removes all key-value entries from the list cache.
     *
     * @private
     * @name clear
     * @memberOf ListCache
     */
    function listCacheClear() {
      this.__data__ = [];
      this.size = 0;
    }

    /**
     * Removes `key` and its value from the list cache.
     *
     * @private
     * @name delete
     * @memberOf ListCache
     * @param {string} key The key of the value to remove.
     * @returns {boolean} Returns `true` if the entry was removed, else `false`.
     */
    function listCacheDelete(key) {
      var data = this.__data__,
          index = assocIndexOf(data, key);

      if (index < 0) {
        return false;
      }
      var lastIndex = data.length - 1;
      if (index == lastIndex) {
        data.pop();
      } else {
        splice.call(data, index, 1);
      }
      --this.size;
      return true;
    }

    /**
     * Gets the list cache value for `key`.
     *
     * @private
     * @name get
     * @memberOf ListCache
     * @param {string} key The key of the value to get.
     * @returns {*} Returns the entry value.
     */
    function listCacheGet(key) {
      var data = this.__data__,
          index = assocIndexOf(data, key);

      return index < 0 ? undefined : data[index][1];
    }

    /**
     * Checks if a list cache value for `key` exists.
     *
     * @private
     * @name has
     * @memberOf ListCache
     * @param {string} key The key of the entry to check.
     * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
     */
    function listCacheHas(key) {
      return assocIndexOf(this.__data__, key) > -1;
    }

    /**
     * Sets the list cache `key` to `value`.
     *
     * @private
     * @name set
     * @memberOf ListCache
     * @param {string} key The key of the value to set.
     * @param {*} value The value to set.
     * @returns {Object} Returns the list cache instance.
     */
    function listCacheSet(key, value) {
      var data = this.__data__,
          index = assocIndexOf(data, key);

      if (index < 0) {
        ++this.size;
        data.push([key, value]);
      } else {
        data[index][1] = value;
      }
      return this;
    }

    // Add methods to `ListCache`.
    ListCache.prototype.clear = listCacheClear;
    ListCache.prototype['delete'] = listCacheDelete;
    ListCache.prototype.get = listCacheGet;
    ListCache.prototype.has = listCacheHas;
    ListCache.prototype.set = listCacheSet;

    /*------------------------------------------------------------------------*/

    /**
     * Creates a map cache object to store key-value pairs.
     *
     * @private
     * @constructor
     * @param {Array} [entries] The key-value pairs to cache.
     */
    function MapCache(entries) {
      var index = -1,
          length = entries == null ? 0 : entries.length;

      this.clear();
      while (++index < length) {
        var entry = entries[index];
        this.set(entry[0], entry[1]);
      }
    }

    /**
     * Removes all key-value entries from the map.
     *
     * @private
     * @name clear
     * @memberOf MapCache
     */
    function mapCacheClear() {
      this.size = 0;
      this.__data__ = {
        'hash': new Hash,
        'map': new (Map || ListCache),
        'string': new Hash
      };
    }

    /**
     * Removes `key` and its value from the map.
     *
     * @private
     * @name delete
     * @memberOf MapCache
     * @param {string} key The key of the value to remove.
     * @returns {boolean} Returns `true` if the entry was removed, else `false`.
     */
    function mapCacheDelete(key) {
      var result = getMapData(this, key)['delete'](key);
      this.size -= result ? 1 : 0;
      return result;
    }

    /**
     * Gets the map value for `key`.
     *
     * @private
     * @name get
     * @memberOf MapCache
     * @param {string} key The key of the value to get.
     * @returns {*} Returns the entry value.
     */
    function mapCacheGet(key) {
      return getMapData(this, key).get(key);
    }

    /**
     * Checks if a map value for `key` exists.
     *
     * @private
     * @name has
     * @memberOf MapCache
     * @param {string} key The key of the entry to check.
     * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
     */
    function mapCacheHas(key) {
      return getMapData(this, key).has(key);
    }

    /**
     * Sets the map `key` to `value`.
     *
     * @private
     * @name set
     * @memberOf MapCache
     * @param {string} key The key of the value to set.
     * @param {*} value The value to set.
     * @returns {Object} Returns the map cache instance.
     */
    function mapCacheSet(key, value) {
      var data = getMapData(this, key),
          size = data.size;

      data.set(key, value);
      this.size += data.size == size ? 0 : 1;
      return this;
    }

    // Add methods to `MapCache`.
    MapCache.prototype.clear = mapCacheClear;
    MapCache.prototype['delete'] = mapCacheDelete;
    MapCache.prototype.get = mapCacheGet;
    MapCache.prototype.has = mapCacheHas;
    MapCache.prototype.set = mapCacheSet;

    /*------------------------------------------------------------------------*/

    /**
     *
     * Creates an array cache object to store unique values.
     *
     * @private
     * @constructor
     * @param {Array} [values] The values to cache.
     */
    function SetCache(values) {
      var index = -1,
          length = values == null ? 0 : values.length;

      this.__data__ = new MapCache;
      while (++index < length) {
        this.add(values[index]);
      }
    }

    /**
     * Adds `value` to the array cache.
     *
     * @private
     * @name add
     * @memberOf SetCache
     * @alias push
     * @param {*} value The value to cache.
     * @returns {Object} Returns the cache instance.
     */
    function setCacheAdd(value) {
      this.__data__.set(value, HASH_UNDEFINED);
      return this;
    }

    /**
     * Checks if `value` is in the array cache.
     *
     * @private
     * @name has
     * @memberOf SetCache
     * @param {*} value The value to search for.
     * @returns {number} Returns `true` if `value` is found, else `false`.
     */
    function setCacheHas(value) {
      return this.__data__.has(value);
    }

    // Add methods to `SetCache`.
    SetCache.prototype.add = SetCache.prototype.push = setCacheAdd;
    SetCache.prototype.has = setCacheHas;

    /*------------------------------------------------------------------------*/

    /**
     * Creates a stack cache object to store key-value pairs.
     *
     * @private
     * @constructor
     * @param {Array} [entries] The key-value pairs to cache.
     */
    function Stack(entries) {
      var data = this.__data__ = new ListCache(entries);
      this.size = data.size;
    }

    /**
     * Removes all key-value entries from the stack.
     *
     * @private
     * @name clear
     * @memberOf Stack
     */
    function stackClear() {
      this.__data__ = new ListCache;
      this.size = 0;
    }

    /**
     * Removes `key` and its value from the stack.
     *
     * @private
     * @name delete
     * @memberOf Stack
     * @param {string} key The key of the value to remove.
     * @returns {boolean} Returns `true` if the entry was removed, else `false`.
     */
    function stackDelete(key) {
      var data = this.__data__,
          result = data['delete'](key);

      this.size = data.size;
      return result;
    }

    /**
     * Gets the stack value for `key`.
     *
     * @private
     * @name get
     * @memberOf Stack
     * @param {string} key The key of the value to get.
     * @returns {*} Returns the entry value.
     */
    function stackGet(key) {
      return this.__data__.get(key);
    }

    /**
     * Checks if a stack value for `key` exists.
     *
     * @private
     * @name has
     * @memberOf Stack
     * @param {string} key The key of the entry to check.
     * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
     */
    function stackHas(key) {
      return this.__data__.has(key);
    }

    /**
     * Sets the stack `key` to `value`.
     *
     * @private
     * @name set
     * @memberOf Stack
     * @param {string} key The key of the value to set.
     * @param {*} value The value to set.
     * @returns {Object} Returns the stack cache instance.
     */
    function stackSet(key, value) {
      var data = this.__data__;
      if (data instanceof ListCache) {
        var pairs = data.__data__;
        if (!Map || (pairs.length < LARGE_ARRAY_SIZE - 1)) {
          pairs.push([key, value]);
          this.size = ++data.size;
          return this;
        }
        data = this.__data__ = new MapCache(pairs);
      }
      data.set(key, value);
      this.size = data.size;
      return this;
    }

    // Add methods to `Stack`.
    Stack.prototype.clear = stackClear;
    Stack.prototype['delete'] = stackDelete;
    Stack.prototype.get = stackGet;
    Stack.prototype.has = stackHas;
    Stack.prototype.set = stackSet;

    /*------------------------------------------------------------------------*/

    /**
     * Creates an array of the enumerable property names of the array-like `value`.
     *
     * @private
     * @param {*} value The value to query.
     * @param {boolean} inherited Specify returning inherited property names.
     * @returns {Array} Returns the array of property names.
     */
    function arrayLikeKeys(value, inherited) {
      var isArr = isArray(value),
          isArg = !isArr && isArguments(value),
          isBuff = !isArr && !isArg && isBuffer(value),
          isType = !isArr && !isArg && !isBuff && isTypedArray(value),
          skipIndexes = isArr || isArg || isBuff || isType,
          result = skipIndexes ? baseTimes(value.length, String) : [],
          length = result.length;

      for (var key in value) {
        if ((inherited || hasOwnProperty.call(value, key)) &&
            !(skipIndexes && (
               // Safari 9 has enumerable `arguments.length` in strict mode.
               key == 'length' ||
               // Node.js 0.10 has enumerable non-index properties on buffers.
               (isBuff && (key == 'offset' || key == 'parent')) ||
               // PhantomJS 2 has enumerable non-index properties on typed arrays.
               (isType && (key == 'buffer' || key == 'byteLength' || key == 'byteOffset')) ||
               // Skip index properties.
               isIndex(key, length)
            ))) {
          result.push(key);
        }
      }
      return result;
    }

    /**
     * A specialized version of `_.sample` for arrays.
     *
     * @private
     * @param {Array} array The array to sample.
     * @returns {*} Returns the random element.
     */
    function arraySample(array) {
      var length = array.length;
      return length ? array[baseRandom(0, length - 1)] : undefined;
    }

    /**
     * A specialized version of `_.sampleSize` for arrays.
     *
     * @private
     * @param {Array} array The array to sample.
     * @param {number} n The number of elements to sample.
     * @returns {Array} Returns the random elements.
     */
    function arraySampleSize(array, n) {
      return shuffleSelf(copyArray(array), baseClamp(n, 0, array.length));
    }

    /**
     * A specialized version of `_.shuffle` for arrays.
     *
     * @private
     * @param {Array} array The array to shuffle.
     * @returns {Array} Returns the new shuffled array.
     */
    function arrayShuffle(array) {
      return shuffleSelf(copyArray(array));
    }

    /**
     * This function is like `assignValue` except that it doesn't assign
     * `undefined` values.
     *
     * @private
     * @param {Object} object The object to modify.
     * @param {string} key The key of the property to assign.
     * @param {*} value The value to assign.
     */
    function assignMergeValue(object, key, value) {
      if ((value !== undefined && !eq(object[key], value)) ||
          (value === undefined && !(key in object))) {
        baseAssignValue(object, key, value);
      }
    }

    /**
     * Assigns `value` to `key` of `object` if the existing value is not equivalent
     * using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
     * for equality comparisons.
     *
     * @private
     * @param {Object} object The object to modify.
     * @param {string} key The key of the property to assign.
     * @param {*} value The value to assign.
     */
    function assignValue(object, key, value) {
      var objValue = object[key];
      if (!(hasOwnProperty.call(object, key) && eq(objValue, value)) ||
          (value === undefined && !(key in object))) {
        baseAssignValue(object, key, value);
      }
    }

    /**
     * Gets the index at which the `key` is found in `array` of key-value pairs.
     *
     * @private
     * @param {Array} array The array to inspect.
     * @param {*} key The key to search for.
     * @returns {number} Returns the index of the matched value, else `-1`.
     */
    function assocIndexOf(array, key) {
      var length = array.length;
      while (length--) {
        if (eq(array[length][0], key)) {
          return length;
        }
      }
      return -1;
    }

    /**
     * Aggregates elements of `collection` on `accumulator` with keys transformed
     * by `iteratee` and values set by `setter`.
     *
     * @private
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} setter The function to set `accumulator` values.
     * @param {Function} iteratee The iteratee to transform keys.
     * @param {Object} accumulator The initial aggregated object.
     * @returns {Function} Returns `accumulator`.
     */
    function baseAggregator(collection, setter, iteratee, accumulator) {
      baseEach(collection, function(value, key, collection) {
        setter(accumulator, value, iteratee(value), collection);
      });
      return accumulator;
    }

    /**
     * The base implementation of `_.assign` without support for multiple sources
     * or `customizer` functions.
     *
     * @private
     * @param {Object} object The destination object.
     * @param {Object} source The source object.
     * @returns {Object} Returns `object`.
     */
    function baseAssign(object, source) {
      return object && copyObject(source, keys(source), object);
    }

    /**
     * The base implementation of `_.assignIn` without support for multiple sources
     * or `customizer` functions.
     *
     * @private
     * @param {Object} object The destination object.
     * @param {Object} source The source object.
     * @returns {Object} Returns `object`.
     */
    function baseAssignIn(object, source) {
      return object && copyObject(source, keysIn(source), object);
    }

    /**
     * The base implementation of `assignValue` and `assignMergeValue` without
     * value checks.
     *
     * @private
     * @param {Object} object The object to modify.
     * @param {string} key The key of the property to assign.
     * @param {*} value The value to assign.
     */
    function baseAssignValue(object, key, value) {
      if (key == '__proto__' && defineProperty) {
        defineProperty(object, key, {
          'configurable': true,
          'enumerable': true,
          'value': value,
          'writable': true
        });
      } else {
        object[key] = value;
      }
    }

    /**
     * The base implementation of `_.at` without support for individual paths.
     *
     * @private
     * @param {Object} object The object to iterate over.
     * @param {string[]} paths The property paths to pick.
     * @returns {Array} Returns the picked elements.
     */
    function baseAt(object, paths) {
      var index = -1,
          length = paths.length,
          result = Array(length),
          skip = object == null;

      while (++index < length) {
        result[index] = skip ? undefined : get(object, paths[index]);
      }
      return result;
    }

    /**
     * The base implementation of `_.clamp` which doesn't coerce arguments.
     *
     * @private
     * @param {number} number The number to clamp.
     * @param {number} [lower] The lower bound.
     * @param {number} upper The upper bound.
     * @returns {number} Returns the clamped number.
     */
    function baseClamp(number, lower, upper) {
      if (number === number) {
        if (upper !== undefined) {
          number = number <= upper ? number : upper;
        }
        if (lower !== undefined) {
          number = number >= lower ? number : lower;
        }
      }
      return number;
    }

    /**
     * The base implementation of `_.clone` and `_.cloneDeep` which tracks
     * traversed objects.
     *
     * @private
     * @param {*} value The value to clone.
     * @param {boolean} bitmask The bitmask flags.
     *  1 - Deep clone
     *  2 - Flatten inherited properties
     *  4 - Clone symbols
     * @param {Function} [customizer] The function to customize cloning.
     * @param {string} [key] The key of `value`.
     * @param {Object} [object] The parent object of `value`.
     * @param {Object} [stack] Tracks traversed objects and their clone counterparts.
     * @returns {*} Returns the cloned value.
     */
    function baseClone(value, bitmask, customizer, key, object, stack) {
      var result,
          isDeep = bitmask & CLONE_DEEP_FLAG,
          isFlat = bitmask & CLONE_FLAT_FLAG,
          isFull = bitmask & CLONE_SYMBOLS_FLAG;

      if (customizer) {
        result = object ? customizer(value, key, object, stack) : customizer(value);
      }
      if (result !== undefined) {
        return result;
      }
      if (!isObject(value)) {
        return value;
      }
      var isArr = isArray(value);
      if (isArr) {
        result = initCloneArray(value);
        if (!isDeep) {
          return copyArray(value, result);
        }
      } else {
        var tag = getTag(value),
            isFunc = tag == funcTag || tag == genTag;

        if (isBuffer(value)) {
          return cloneBuffer(value, isDeep);
        }
        if (tag == objectTag || tag == argsTag || (isFunc && !object)) {
          result = (isFlat || isFunc) ? {} : initCloneObject(value);
          if (!isDeep) {
            return isFlat
              ? copySymbolsIn(value, baseAssignIn(result, value))
              : copySymbols(value, baseAssign(result, value));
          }
        } else {
          if (!cloneableTags[tag]) {
            return object ? value : {};
          }
          result = initCloneByTag(value, tag, baseClone, isDeep);
        }
      }
      // Check for circular references and return its corresponding clone.
      stack || (stack = new Stack);
      var stacked = stack.get(value);
      if (stacked) {
        return stacked;
      }
      stack.set(value, result);

      var keysFunc = isFull
        ? (isFlat ? getAllKeysIn : getAllKeys)
        : (isFlat ? keysIn : keys);

      var props = isArr ? undefined : keysFunc(value);
      arrayEach(props || value, function(subValue, key) {
        if (props) {
          key = subValue;
          subValue = value[key];
        }
        // Recursively populate clone (susceptible to call stack limits).
        assignValue(result, key, baseClone(subValue, bitmask, customizer, key, value, stack));
      });
      return result;
    }

    /**
     * The base implementation of `_.conforms` which doesn't clone `source`.
     *
     * @private
     * @param {Object} source The object of property predicates to conform to.
     * @returns {Function} Returns the new spec function.
     */
    function baseConforms(source) {
      var props = keys(source);
      return function(object) {
        return baseConformsTo(object, source, props);
      };
    }

    /**
     * The base implementation of `_.conformsTo` which accepts `props` to check.
     *
     * @private
     * @param {Object} object The object to inspect.
     * @param {Object} source The object of property predicates to conform to.
     * @returns {boolean} Returns `true` if `object` conforms, else `false`.
     */
    function baseConformsTo(object, source, props) {
      var length = props.length;
      if (object == null) {
        return !length;
      }
      object = Object(object);
      while (length--) {
        var key = props[length],
            predicate = source[key],
            value = object[key];

        if ((value === undefined && !(key in object)) || !predicate(value)) {
          return false;
        }
      }
      return true;
    }

    /**
     * The base implementation of `_.delay` and `_.defer` which accepts `args`
     * to provide to `func`.
     *
     * @private
     * @param {Function} func The function to delay.
     * @param {number} wait The number of milliseconds to delay invocation.
     * @param {Array} args The arguments to provide to `func`.
     * @returns {number|Object} Returns the timer id or timeout object.
     */
    function baseDelay(func, wait, args) {
      if (typeof func != 'function') {
        throw new TypeError(FUNC_ERROR_TEXT);
      }
      return setTimeout(function() { func.apply(undefined, args); }, wait);
    }

    /**
     * The base implementation of methods like `_.difference` without support
     * for excluding multiple arrays or iteratee shorthands.
     *
     * @private
     * @param {Array} array The array to inspect.
     * @param {Array} values The values to exclude.
     * @param {Function} [iteratee] The iteratee invoked per element.
     * @param {Function} [comparator] The comparator invoked per element.
     * @returns {Array} Returns the new array of filtered values.
     */
    function baseDifference(array, values, iteratee, comparator) {
      var index = -1,
          includes = arrayIncludes,
          isCommon = true,
          length = array.length,
          result = [],
          valuesLength = values.length;

      if (!length) {
        return result;
      }
      if (iteratee) {
        values = arrayMap(values, baseUnary(iteratee));
      }
      if (comparator) {
        includes = arrayIncludesWith;
        isCommon = false;
      }
      else if (values.length >= LARGE_ARRAY_SIZE) {
        includes = cacheHas;
        isCommon = false;
        values = new SetCache(values);
      }
      outer:
      while (++index < length) {
        var value = array[index],
            computed = iteratee == null ? value : iteratee(value);

        value = (comparator || value !== 0) ? value : 0;
        if (isCommon && computed === computed) {
          var valuesIndex = valuesLength;
          while (valuesIndex--) {
            if (values[valuesIndex] === computed) {
              continue outer;
            }
          }
          result.push(value);
        }
        else if (!includes(values, computed, comparator)) {
          result.push(value);
        }
      }
      return result;
    }

    /**
     * The base implementation of `_.forEach` without support for iteratee shorthands.
     *
     * @private
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} iteratee The function invoked per iteration.
     * @returns {Array|Object} Returns `collection`.
     */
    var baseEach = createBaseEach(baseForOwn);

    /**
     * The base implementation of `_.forEachRight` without support for iteratee shorthands.
     *
     * @private
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} iteratee The function invoked per iteration.
     * @returns {Array|Object} Returns `collection`.
     */
    var baseEachRight = createBaseEach(baseForOwnRight, true);

    /**
     * The base implementation of `_.every` without support for iteratee shorthands.
     *
     * @private
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} predicate The function invoked per iteration.
     * @returns {boolean} Returns `true` if all elements pass the predicate check,
     *  else `false`
     */
    function baseEvery(collection, predicate) {
      var result = true;
      baseEach(collection, function(value, index, collection) {
        result = !!predicate(value, index, collection);
        return result;
      });
      return result;
    }

    /**
     * The base implementation of methods like `_.max` and `_.min` which accepts a
     * `comparator` to determine the extremum value.
     *
     * @private
     * @param {Array} array The array to iterate over.
     * @param {Function} iteratee The iteratee invoked per iteration.
     * @param {Function} comparator The comparator used to compare values.
     * @returns {*} Returns the extremum value.
     */
    function baseExtremum(array, iteratee, comparator) {
      var index = -1,
          length = array.length;

      while (++index < length) {
        var value = array[index],
            current = iteratee(value);

        if (current != null && (computed === undefined
              ? (current === current && !isSymbol(current))
              : comparator(current, computed)
            )) {
          var computed = current,
              result = value;
        }
      }
      return result;
    }

    /**
     * The base implementation of `_.fill` without an iteratee call guard.
     *
     * @private
     * @param {Array} array The array to fill.
     * @param {*} value The value to fill `array` with.
     * @param {number} [start=0] The start position.
     * @param {number} [end=array.length] The end position.
     * @returns {Array} Returns `array`.
     */
    function baseFill(array, value, start, end) {
      var length = array.length;

      start = toInteger(start);
      if (start < 0) {
        start = -start > length ? 0 : (length + start);
      }
      end = (end === undefined || end > length) ? length : toInteger(end);
      if (end < 0) {
        end += length;
      }
      end = start > end ? 0 : toLength(end);
      while (start < end) {
        array[start++] = value;
      }
      return array;
    }

    /**
     * The base implementation of `_.filter` without support for iteratee shorthands.
     *
     * @private
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} predicate The function invoked per iteration.
     * @returns {Array} Returns the new filtered array.
     */
    function baseFilter(collection, predicate) {
      var result = [];
      baseEach(collection, function(value, index, collection) {
        if (predicate(value, index, collection)) {
          result.push(value);
        }
      });
      return result;
    }

    /**
     * The base implementation of `_.flatten` with support for restricting flattening.
     *
     * @private
     * @param {Array} array The array to flatten.
     * @param {number} depth The maximum recursion depth.
     * @param {boolean} [predicate=isFlattenable] The function invoked per iteration.
     * @param {boolean} [isStrict] Restrict to values that pass `predicate` checks.
     * @param {Array} [result=[]] The initial result value.
     * @returns {Array} Returns the new flattened array.
     */
    function baseFlatten(array, depth, predicate, isStrict, result) {
      var index = -1,
          length = array.length;

      predicate || (predicate = isFlattenable);
      result || (result = []);

      while (++index < length) {
        var value = array[index];
        if (depth > 0 && predicate(value)) {
          if (depth > 1) {
            // Recursively flatten arrays (susceptible to call stack limits).
            baseFlatten(value, depth - 1, predicate, isStrict, result);
          } else {
            arrayPush(result, value);
          }
        } else if (!isStrict) {
          result[result.length] = value;
        }
      }
      return result;
    }

    /**
     * The base implementation of `baseForOwn` which iterates over `object`
     * properties returned by `keysFunc` and invokes `iteratee` for each property.
     * Iteratee functions may exit iteration early by explicitly returning `false`.
     *
     * @private
     * @param {Object} object The object to iterate over.
     * @param {Function} iteratee The function invoked per iteration.
     * @param {Function} keysFunc The function to get the keys of `object`.
     * @returns {Object} Returns `object`.
     */
    var baseFor = createBaseFor();

    /**
     * This function is like `baseFor` except that it iterates over properties
     * in the opposite order.
     *
     * @private
     * @param {Object} object The object to iterate over.
     * @param {Function} iteratee The function invoked per iteration.
     * @param {Function} keysFunc The function to get the keys of `object`.
     * @returns {Object} Returns `object`.
     */
    var baseForRight = createBaseFor(true);

    /**
     * The base implementation of `_.forOwn` without support for iteratee shorthands.
     *
     * @private
     * @param {Object} object The object to iterate over.
     * @param {Function} iteratee The function invoked per iteration.
     * @returns {Object} Returns `object`.
     */
    function baseForOwn(object, iteratee) {
      return object && baseFor(object, iteratee, keys);
    }

    /**
     * The base implementation of `_.forOwnRight` without support for iteratee shorthands.
     *
     * @private
     * @param {Object} object The object to iterate over.
     * @param {Function} iteratee The function invoked per iteration.
     * @returns {Object} Returns `object`.
     */
    function baseForOwnRight(object, iteratee) {
      return object && baseForRight(object, iteratee, keys);
    }

    /**
     * The base implementation of `_.functions` which creates an array of
     * `object` function property names filtered from `props`.
     *
     * @private
     * @param {Object} object The object to inspect.
     * @param {Array} props The property names to filter.
     * @returns {Array} Returns the function names.
     */
    function baseFunctions(object, props) {
      return arrayFilter(props, function(key) {
        return isFunction(object[key]);
      });
    }

    /**
     * The base implementation of `_.get` without support for default values.
     *
     * @private
     * @param {Object} object The object to query.
     * @param {Array|string} path The path of the property to get.
     * @returns {*} Returns the resolved value.
     */
    function baseGet(object, path) {
      path = castPath(path, object);

      var index = 0,
          length = path.length;

      while (object != null && index < length) {
        object = object[toKey(path[index++])];
      }
      return (index && index == length) ? object : undefined;
    }

    /**
     * The base implementation of `getAllKeys` and `getAllKeysIn` which uses
     * `keysFunc` and `symbolsFunc` to get the enumerable property names and
     * symbols of `object`.
     *
     * @private
     * @param {Object} object The object to query.
     * @param {Function} keysFunc The function to get the keys of `object`.
     * @param {Function} symbolsFunc The function to get the symbols of `object`.
     * @returns {Array} Returns the array of property names and symbols.
     */
    function baseGetAllKeys(object, keysFunc, symbolsFunc) {
      var result = keysFunc(object);
      return isArray(object) ? result : arrayPush(result, symbolsFunc(object));
    }

    /**
     * The base implementation of `getTag` without fallbacks for buggy environments.
     *
     * @private
     * @param {*} value The value to query.
     * @returns {string} Returns the `toStringTag`.
     */
    function baseGetTag(value) {
      if (value == null) {
        return value === undefined ? undefinedTag : nullTag;
      }
      return (symToStringTag && symToStringTag in Object(value))
        ? getRawTag(value)
        : objectToString(value);
    }

    /**
     * The base implementation of `_.gt` which doesn't coerce arguments.
     *
     * @private
     * @param {*} value The value to compare.
     * @param {*} other The other value to compare.
     * @returns {boolean} Returns `true` if `value` is greater than `other`,
     *  else `false`.
     */
    function baseGt(value, other) {
      return value > other;
    }

    /**
     * The base implementation of `_.has` without support for deep paths.
     *
     * @private
     * @param {Object} [object] The object to query.
     * @param {Array|string} key The key to check.
     * @returns {boolean} Returns `true` if `key` exists, else `false`.
     */
    function baseHas(object, key) {
      return object != null && hasOwnProperty.call(object, key);
    }

    /**
     * The base implementation of `_.hasIn` without support for deep paths.
     *
     * @private
     * @param {Object} [object] The object to query.
     * @param {Array|string} key The key to check.
     * @returns {boolean} Returns `true` if `key` exists, else `false`.
     */
    function baseHasIn(object, key) {
      return object != null && key in Object(object);
    }

    /**
     * The base implementation of `_.inRange` which doesn't coerce arguments.
     *
     * @private
     * @param {number} number The number to check.
     * @param {number} start The start of the range.
     * @param {number} end The end of the range.
     * @returns {boolean} Returns `true` if `number` is in the range, else `false`.
     */
    function baseInRange(number, start, end) {
      return number >= nativeMin(start, end) && number < nativeMax(start, end);
    }

    /**
     * The base implementation of methods like `_.intersection`, without support
     * for iteratee shorthands, that accepts an array of arrays to inspect.
     *
     * @private
     * @param {Array} arrays The arrays to inspect.
     * @param {Function} [iteratee] The iteratee invoked per element.
     * @param {Function} [comparator] The comparator invoked per element.
     * @returns {Array} Returns the new array of shared values.
     */
    function baseIntersection(arrays, iteratee, comparator) {
      var includes = comparator ? arrayIncludesWith : arrayIncludes,
          length = arrays[0].length,
          othLength = arrays.length,
          othIndex = othLength,
          caches = Array(othLength),
          maxLength = Infinity,
          result = [];

      while (othIndex--) {
        var array = arrays[othIndex];
        if (othIndex && iteratee) {
          array = arrayMap(array, baseUnary(iteratee));
        }
        maxLength = nativeMin(array.length, maxLength);
        caches[othIndex] = !comparator && (iteratee || (length >= 120 && array.length >= 120))
          ? new SetCache(othIndex && array)
          : undefined;
      }
      array = arrays[0];

      var index = -1,
          seen = caches[0];

      outer:
      while (++index < length && result.length < maxLength) {
        var value = array[index],
            computed = iteratee ? iteratee(value) : value;

        value = (comparator || value !== 0) ? value : 0;
        if (!(seen
              ? cacheHas(seen, computed)
              : includes(result, computed, comparator)
            )) {
          othIndex = othLength;
          while (--othIndex) {
            var cache = caches[othIndex];
            if (!(cache
                  ? cacheHas(cache, computed)
                  : includes(arrays[othIndex], computed, comparator))
                ) {
              continue outer;
            }
          }
          if (seen) {
            seen.push(computed);
          }
          result.push(value);
        }
      }
      return result;
    }

    /**
     * The base implementation of `_.invert` and `_.invertBy` which inverts
     * `object` with values transformed by `iteratee` and set by `setter`.
     *
     * @private
     * @param {Object} object The object to iterate over.
     * @param {Function} setter The function to set `accumulator` values.
     * @param {Function} iteratee The iteratee to transform values.
     * @param {Object} accumulator The initial inverted object.
     * @returns {Function} Returns `accumulator`.
     */
    function baseInverter(object, setter, iteratee, accumulator) {
      baseForOwn(object, function(value, key, object) {
        setter(accumulator, iteratee(value), key, object);
      });
      return accumulator;
    }

    /**
     * The base implementation of `_.invoke` without support for individual
     * method arguments.
     *
     * @private
     * @param {Object} object The object to query.
     * @param {Array|string} path The path of the method to invoke.
     * @param {Array} args The arguments to invoke the method with.
     * @returns {*} Returns the result of the invoked method.
     */
    function baseInvoke(object, path, args) {
      path = castPath(path, object);
      object = parent(object, path);
      var func = object == null ? object : object[toKey(last(path))];
      return func == null ? undefined : apply(func, object, args);
    }

    /**
     * The base implementation of `_.isArguments`.
     *
     * @private
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is an `arguments` object,
     */
    function baseIsArguments(value) {
      return isObjectLike(value) && baseGetTag(value) == argsTag;
    }

    /**
     * The base implementation of `_.isArrayBuffer` without Node.js optimizations.
     *
     * @private
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is an array buffer, else `false`.
     */
    function baseIsArrayBuffer(value) {
      return isObjectLike(value) && baseGetTag(value) == arrayBufferTag;
    }

    /**
     * The base implementation of `_.isDate` without Node.js optimizations.
     *
     * @private
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a date object, else `false`.
     */
    function baseIsDate(value) {
      return isObjectLike(value) && baseGetTag(value) == dateTag;
    }

    /**
     * The base implementation of `_.isEqual` which supports partial comparisons
     * and tracks traversed objects.
     *
     * @private
     * @param {*} value The value to compare.
     * @param {*} other The other value to compare.
     * @param {boolean} bitmask The bitmask flags.
     *  1 - Unordered comparison
     *  2 - Partial comparison
     * @param {Function} [customizer] The function to customize comparisons.
     * @param {Object} [stack] Tracks traversed `value` and `other` objects.
     * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
     */
    function baseIsEqual(value, other, bitmask, customizer, stack) {
      if (value === other) {
        return true;
      }
      if (value == null || other == null || (!isObjectLike(value) && !isObjectLike(other))) {
        return value !== value && other !== other;
      }
      return baseIsEqualDeep(value, other, bitmask, customizer, baseIsEqual, stack);
    }

    /**
     * A specialized version of `baseIsEqual` for arrays and objects which performs
     * deep comparisons and tracks traversed objects enabling objects with circular
     * references to be compared.
     *
     * @private
     * @param {Object} object The object to compare.
     * @param {Object} other The other object to compare.
     * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details.
     * @param {Function} customizer The function to customize comparisons.
     * @param {Function} equalFunc The function to determine equivalents of values.
     * @param {Object} [stack] Tracks traversed `object` and `other` objects.
     * @returns {boolean} Returns `true` if the objects are equivalent, else `false`.
     */
    function baseIsEqualDeep(object, other, bitmask, customizer, equalFunc, stack) {
      var objIsArr = isArray(object),
          othIsArr = isArray(other),
          objTag = objIsArr ? arrayTag : getTag(object),
          othTag = othIsArr ? arrayTag : getTag(other);

      objTag = objTag == argsTag ? objectTag : objTag;
      othTag = othTag == argsTag ? objectTag : othTag;

      var objIsObj = objTag == objectTag,
          othIsObj = othTag == objectTag,
          isSameTag = objTag == othTag;

      if (isSameTag && isBuffer(object)) {
        if (!isBuffer(other)) {
          return false;
        }
        objIsArr = true;
        objIsObj = false;
      }
      if (isSameTag && !objIsObj) {
        stack || (stack = new Stack);
        return (objIsArr || isTypedArray(object))
          ? equalArrays(object, other, bitmask, customizer, equalFunc, stack)
          : equalByTag(object, other, objTag, bitmask, customizer, equalFunc, stack);
      }
      if (!(bitmask & COMPARE_PARTIAL_FLAG)) {
        var objIsWrapped = objIsObj && hasOwnProperty.call(object, '__wrapped__'),
            othIsWrapped = othIsObj && hasOwnProperty.call(other, '__wrapped__');

        if (objIsWrapped || othIsWrapped) {
          var objUnwrapped = objIsWrapped ? object.value() : object,
              othUnwrapped = othIsWrapped ? other.value() : other;

          stack || (stack = new Stack);
          return equalFunc(objUnwrapped, othUnwrapped, bitmask, customizer, stack);
        }
      }
      if (!isSameTag) {
        return false;
      }
      stack || (stack = new Stack);
      return equalObjects(object, other, bitmask, customizer, equalFunc, stack);
    }

    /**
     * The base implementation of `_.isMap` without Node.js optimizations.
     *
     * @private
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a map, else `false`.
     */
    function baseIsMap(value) {
      return isObjectLike(value) && getTag(value) == mapTag;
    }

    /**
     * The base implementation of `_.isMatch` without support for iteratee shorthands.
     *
     * @private
     * @param {Object} object The object to inspect.
     * @param {Object} source The object of property values to match.
     * @param {Array} matchData The property names, values, and compare flags to match.
     * @param {Function} [customizer] The function to customize comparisons.
     * @returns {boolean} Returns `true` if `object` is a match, else `false`.
     */
    function baseIsMatch(object, source, matchData, customizer) {
      var index = matchData.length,
          length = index,
          noCustomizer = !customizer;

      if (object == null) {
        return !length;
      }
      object = Object(object);
      while (index--) {
        var data = matchData[index];
        if ((noCustomizer && data[2])
              ? data[1] !== object[data[0]]
              : !(data[0] in object)
            ) {
          return false;
        }
      }
      while (++index < length) {
        data = matchData[index];
        var key = data[0],
            objValue = object[key],
            srcValue = data[1];

        if (noCustomizer && data[2]) {
          if (objValue === undefined && !(key in object)) {
            return false;
          }
        } else {
          var stack = new Stack;
          if (customizer) {
            var result = customizer(objValue, srcValue, key, object, source, stack);
          }
          if (!(result === undefined
                ? baseIsEqual(srcValue, objValue, COMPARE_PARTIAL_FLAG | COMPARE_UNORDERED_FLAG, customizer, stack)
                : result
              )) {
            return false;
          }
        }
      }
      return true;
    }

    /**
     * The base implementation of `_.isNative` without bad shim checks.
     *
     * @private
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a native function,
     *  else `false`.
     */
    function baseIsNative(value) {
      if (!isObject(value) || isMasked(value)) {
        return false;
      }
      var pattern = isFunction(value) ? reIsNative : reIsHostCtor;
      return pattern.test(toSource(value));
    }

    /**
     * The base implementation of `_.isRegExp` without Node.js optimizations.
     *
     * @private
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a regexp, else `false`.
     */
    function baseIsRegExp(value) {
      return isObjectLike(value) && baseGetTag(value) == regexpTag;
    }

    /**
     * The base implementation of `_.isSet` without Node.js optimizations.
     *
     * @private
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a set, else `false`.
     */
    function baseIsSet(value) {
      return isObjectLike(value) && getTag(value) == setTag;
    }

    /**
     * The base implementation of `_.isTypedArray` without Node.js optimizations.
     *
     * @private
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a typed array, else `false`.
     */
    function baseIsTypedArray(value) {
      return isObjectLike(value) &&
        isLength(value.length) && !!typedArrayTags[baseGetTag(value)];
    }

    /**
     * The base implementation of `_.iteratee`.
     *
     * @private
     * @param {*} [value=_.identity] The value to convert to an iteratee.
     * @returns {Function} Returns the iteratee.
     */
    function baseIteratee(value) {
      // Don't store the `typeof` result in a variable to avoid a JIT bug in Safari 9.
      // See https://bugs.webkit.org/show_bug.cgi?id=156034 for more details.
      if (typeof value == 'function') {
        return value;
      }
      if (value == null) {
        return identity;
      }
      if (typeof value == 'object') {
        return isArray(value)
          ? baseMatchesProperty(value[0], value[1])
          : baseMatches(value);
      }
      return property(value);
    }

    /**
     * The base implementation of `_.keys` which doesn't treat sparse arrays as dense.
     *
     * @private
     * @param {Object} object The object to query.
     * @returns {Array} Returns the array of property names.
     */
    function baseKeys(object) {
      if (!isPrototype(object)) {
        return nativeKeys(object);
      }
      var result = [];
      for (var key in Object(object)) {
        if (hasOwnProperty.call(object, key) && key != 'constructor') {
          result.push(key);
        }
      }
      return result;
    }

    /**
     * The base implementation of `_.keysIn` which doesn't treat sparse arrays as dense.
     *
     * @private
     * @param {Object} object The object to query.
     * @returns {Array} Returns the array of property names.
     */
    function baseKeysIn(object) {
      if (!isObject(object)) {
        return nativeKeysIn(object);
      }
      var isProto = isPrototype(object),
          result = [];

      for (var key in object) {
        if (!(key == 'constructor' && (isProto || !hasOwnProperty.call(object, key)))) {
          result.push(key);
        }
      }
      return result;
    }

    /**
     * The base implementation of `_.lt` which doesn't coerce arguments.
     *
     * @private
     * @param {*} value The value to compare.
     * @param {*} other The other value to compare.
     * @returns {boolean} Returns `true` if `value` is less than `other`,
     *  else `false`.
     */
    function baseLt(value, other) {
      return value < other;
    }

    /**
     * The base implementation of `_.map` without support for iteratee shorthands.
     *
     * @private
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} iteratee The function invoked per iteration.
     * @returns {Array} Returns the new mapped array.
     */
    function baseMap(collection, iteratee) {
      var index = -1,
          result = isArrayLike(collection) ? Array(collection.length) : [];

      baseEach(collection, function(value, key, collection) {
        result[++index] = iteratee(value, key, collection);
      });
      return result;
    }

    /**
     * The base implementation of `_.matches` which doesn't clone `source`.
     *
     * @private
     * @param {Object} source The object of property values to match.
     * @returns {Function} Returns the new spec function.
     */
    function baseMatches(source) {
      var matchData = getMatchData(source);
      if (matchData.length == 1 && matchData[0][2]) {
        return matchesStrictComparable(matchData[0][0], matchData[0][1]);
      }
      return function(object) {
        return object === source || baseIsMatch(object, source, matchData);
      };
    }

    /**
     * The base implementation of `_.matchesProperty` which doesn't clone `srcValue`.
     *
     * @private
     * @param {string} path The path of the property to get.
     * @param {*} srcValue The value to match.
     * @returns {Function} Returns the new spec function.
     */
    function baseMatchesProperty(path, srcValue) {
      if (isKey(path) && isStrictComparable(srcValue)) {
        return matchesStrictComparable(toKey(path), srcValue);
      }
      return function(object) {
        var objValue = get(object, path);
        return (objValue === undefined && objValue === srcValue)
          ? hasIn(object, path)
          : baseIsEqual(srcValue, objValue, COMPARE_PARTIAL_FLAG | COMPARE_UNORDERED_FLAG);
      };
    }

    /**
     * The base implementation of `_.merge` without support for multiple sources.
     *
     * @private
     * @param {Object} object The destination object.
     * @param {Object} source The source object.
     * @param {number} srcIndex The index of `source`.
     * @param {Function} [customizer] The function to customize merged values.
     * @param {Object} [stack] Tracks traversed source values and their merged
     *  counterparts.
     */
    function baseMerge(object, source, srcIndex, customizer, stack) {
      if (object === source) {
        return;
      }
      baseFor(source, function(srcValue, key) {
        if (isObject(srcValue)) {
          stack || (stack = new Stack);
          baseMergeDeep(object, source, key, srcIndex, baseMerge, customizer, stack);
        }
        else {
          var newValue = customizer
            ? customizer(object[key], srcValue, (key + ''), object, source, stack)
            : undefined;

          if (newValue === undefined) {
            newValue = srcValue;
          }
          assignMergeValue(object, key, newValue);
        }
      }, keysIn);
    }

    /**
     * A specialized version of `baseMerge` for arrays and objects which performs
     * deep merges and tracks traversed objects enabling objects with circular
     * references to be merged.
     *
     * @private
     * @param {Object} object The destination object.
     * @param {Object} source The source object.
     * @param {string} key The key of the value to merge.
     * @param {number} srcIndex The index of `source`.
     * @param {Function} mergeFunc The function to merge values.
     * @param {Function} [customizer] The function to customize assigned values.
     * @param {Object} [stack] Tracks traversed source values and their merged
     *  counterparts.
     */
    function baseMergeDeep(object, source, key, srcIndex, mergeFunc, customizer, stack) {
      var objValue = object[key],
          srcValue = source[key],
          stacked = stack.get(srcValue);

      if (stacked) {
        assignMergeValue(object, key, stacked);
        return;
      }
      var newValue = customizer
        ? customizer(objValue, srcValue, (key + ''), object, source, stack)
        : undefined;

      var isCommon = newValue === undefined;

      if (isCommon) {
        var isArr = isArray(srcValue),
            isBuff = !isArr && isBuffer(srcValue),
            isTyped = !isArr && !isBuff && isTypedArray(srcValue);

        newValue = srcValue;
        if (isArr || isBuff || isTyped) {
          if (isArray(objValue)) {
            newValue = objValue;
          }
          else if (isArrayLikeObject(objValue)) {
            newValue = copyArray(objValue);
          }
          else if (isBuff) {
            isCommon = false;
            newValue = cloneBuffer(srcValue, true);
          }
          else if (isTyped) {
            isCommon = false;
            newValue = cloneTypedArray(srcValue, true);
          }
          else {
            newValue = [];
          }
        }
        else if (isPlainObject(srcValue) || isArguments(srcValue)) {
          newValue = objValue;
          if (isArguments(objValue)) {
            newValue = toPlainObject(objValue);
          }
          else if (!isObject(objValue) || (srcIndex && isFunction(objValue))) {
            newValue = initCloneObject(srcValue);
          }
        }
        else {
          isCommon = false;
        }
      }
      if (isCommon) {
        // Recursively merge objects and arrays (susceptible to call stack limits).
        stack.set(srcValue, newValue);
        mergeFunc(newValue, srcValue, srcIndex, customizer, stack);
        stack['delete'](srcValue);
      }
      assignMergeValue(object, key, newValue);
    }

    /**
     * The base implementation of `_.nth` which doesn't coerce arguments.
     *
     * @private
     * @param {Array} array The array to query.
     * @param {number} n The index of the element to return.
     * @returns {*} Returns the nth element of `array`.
     */
    function baseNth(array, n) {
      var length = array.length;
      if (!length) {
        return;
      }
      n += n < 0 ? length : 0;
      return isIndex(n, length) ? array[n] : undefined;
    }

    /**
     * The base implementation of `_.orderBy` without param guards.
     *
     * @private
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function[]|Object[]|string[]} iteratees The iteratees to sort by.
     * @param {string[]} orders The sort orders of `iteratees`.
     * @returns {Array} Returns the new sorted array.
     */
    function baseOrderBy(collection, iteratees, orders) {
      var index = -1;
      iteratees = arrayMap(iteratees.length ? iteratees : [identity], baseUnary(getIteratee()));

      var result = baseMap(collection, function(value, key, collection) {
        var criteria = arrayMap(iteratees, function(iteratee) {
          return iteratee(value);
        });
        return { 'criteria': criteria, 'index': ++index, 'value': value };
      });

      return baseSortBy(result, function(object, other) {
        return compareMultiple(object, other, orders);
      });
    }

    /**
     * The base implementation of `_.pick` without support for individual
     * property identifiers.
     *
     * @private
     * @param {Object} object The source object.
     * @param {string[]} paths The property paths to pick.
     * @returns {Object} Returns the new object.
     */
    function basePick(object, paths) {
      return basePickBy(object, paths, function(value, path) {
        return hasIn(object, path);
      });
    }

    /**
     * The base implementation of  `_.pickBy` without support for iteratee shorthands.
     *
     * @private
     * @param {Object} object The source object.
     * @param {string[]} paths The property paths to pick.
     * @param {Function} predicate The function invoked per property.
     * @returns {Object} Returns the new object.
     */
    function basePickBy(object, paths, predicate) {
      var index = -1,
          length = paths.length,
          result = {};

      while (++index < length) {
        var path = paths[index],
            value = baseGet(object, path);

        if (predicate(value, path)) {
          baseSet(result, castPath(path, object), value);
        }
      }
      return result;
    }

    /**
     * A specialized version of `baseProperty` which supports deep paths.
     *
     * @private
     * @param {Array|string} path The path of the property to get.
     * @returns {Function} Returns the new accessor function.
     */
    function basePropertyDeep(path) {
      return function(object) {
        return baseGet(object, path);
      };
    }

    /**
     * The base implementation of `_.pullAllBy` without support for iteratee
     * shorthands.
     *
     * @private
     * @param {Array} array The array to modify.
     * @param {Array} values The values to remove.
     * @param {Function} [iteratee] The iteratee invoked per element.
     * @param {Function} [comparator] The comparator invoked per element.
     * @returns {Array} Returns `array`.
     */
    function basePullAll(array, values, iteratee, comparator) {
      var indexOf = comparator ? baseIndexOfWith : baseIndexOf,
          index = -1,
          length = values.length,
          seen = array;

      if (array === values) {
        values = copyArray(values);
      }
      if (iteratee) {
        seen = arrayMap(array, baseUnary(iteratee));
      }
      while (++index < length) {
        var fromIndex = 0,
            value = values[index],
            computed = iteratee ? iteratee(value) : value;

        while ((fromIndex = indexOf(seen, computed, fromIndex, comparator)) > -1) {
          if (seen !== array) {
            splice.call(seen, fromIndex, 1);
          }
          splice.call(array, fromIndex, 1);
        }
      }
      return array;
    }

    /**
     * The base implementation of `_.pullAt` without support for individual
     * indexes or capturing the removed elements.
     *
     * @private
     * @param {Array} array The array to modify.
     * @param {number[]} indexes The indexes of elements to remove.
     * @returns {Array} Returns `array`.
     */
    function basePullAt(array, indexes) {
      var length = array ? indexes.length : 0,
          lastIndex = length - 1;

      while (length--) {
        var index = indexes[length];
        if (length == lastIndex || index !== previous) {
          var previous = index;
          if (isIndex(index)) {
            splice.call(array, index, 1);
          } else {
            baseUnset(array, index);
          }
        }
      }
      return array;
    }

    /**
     * The base implementation of `_.random` without support for returning
     * floating-point numbers.
     *
     * @private
     * @param {number} lower The lower bound.
     * @param {number} upper The upper bound.
     * @returns {number} Returns the random number.
     */
    function baseRandom(lower, upper) {
      return lower + nativeFloor(nativeRandom() * (upper - lower + 1));
    }

    /**
     * The base implementation of `_.range` and `_.rangeRight` which doesn't
     * coerce arguments.
     *
     * @private
     * @param {number} start The start of the range.
     * @param {number} end The end of the range.
     * @param {number} step The value to increment or decrement by.
     * @param {boolean} [fromRight] Specify iterating from right to left.
     * @returns {Array} Returns the range of numbers.
     */
    function baseRange(start, end, step, fromRight) {
      var index = -1,
          length = nativeMax(nativeCeil((end - start) / (step || 1)), 0),
          result = Array(length);

      while (length--) {
        result[fromRight ? length : ++index] = start;
        start += step;
      }
      return result;
    }

    /**
     * The base implementation of `_.repeat` which doesn't coerce arguments.
     *
     * @private
     * @param {string} string The string to repeat.
     * @param {number} n The number of times to repeat the string.
     * @returns {string} Returns the repeated string.
     */
    function baseRepeat(string, n) {
      var result = '';
      if (!string || n < 1 || n > MAX_SAFE_INTEGER) {
        return result;
      }
      // Leverage the exponentiation by squaring algorithm for a faster repeat.
      // See https://en.wikipedia.org/wiki/Exponentiation_by_squaring for more details.
      do {
        if (n % 2) {
          result += string;
        }
        n = nativeFloor(n / 2);
        if (n) {
          string += string;
        }
      } while (n);

      return result;
    }

    /**
     * The base implementation of `_.rest` which doesn't validate or coerce arguments.
     *
     * @private
     * @param {Function} func The function to apply a rest parameter to.
     * @param {number} [start=func.length-1] The start position of the rest parameter.
     * @returns {Function} Returns the new function.
     */
    function baseRest(func, start) {
      return setToString(overRest(func, start, identity), func + '');
    }

    /**
     * The base implementation of `_.sample`.
     *
     * @private
     * @param {Array|Object} collection The collection to sample.
     * @returns {*} Returns the random element.
     */
    function baseSample(collection) {
      return arraySample(values(collection));
    }

    /**
     * The base implementation of `_.sampleSize` without param guards.
     *
     * @private
     * @param {Array|Object} collection The collection to sample.
     * @param {number} n The number of elements to sample.
     * @returns {Array} Returns the random elements.
     */
    function baseSampleSize(collection, n) {
      var array = values(collection);
      return shuffleSelf(array, baseClamp(n, 0, array.length));
    }

    /**
     * The base implementation of `_.set`.
     *
     * @private
     * @param {Object} object The object to modify.
     * @param {Array|string} path The path of the property to set.
     * @param {*} value The value to set.
     * @param {Function} [customizer] The function to customize path creation.
     * @returns {Object} Returns `object`.
     */
    function baseSet(object, path, value, customizer) {
      if (!isObject(object)) {
        return object;
      }
      path = castPath(path, object);

      var index = -1,
          length = path.length,
          lastIndex = length - 1,
          nested = object;

      while (nested != null && ++index < length) {
        var key = toKey(path[index]),
            newValue = value;

        if (index != lastIndex) {
          var objValue = nested[key];
          newValue = customizer ? customizer(objValue, key, nested) : undefined;
          if (newValue === undefined) {
            newValue = isObject(objValue)
              ? objValue
              : (isIndex(path[index + 1]) ? [] : {});
          }
        }
        assignValue(nested, key, newValue);
        nested = nested[key];
      }
      return object;
    }

    /**
     * The base implementation of `setData` without support for hot loop shorting.
     *
     * @private
     * @param {Function} func The function to associate metadata with.
     * @param {*} data The metadata.
     * @returns {Function} Returns `func`.
     */
    var baseSetData = !metaMap ? identity : function(func, data) {
      metaMap.set(func, data);
      return func;
    };

    /**
     * The base implementation of `setToString` without support for hot loop shorting.
     *
     * @private
     * @param {Function} func The function to modify.
     * @param {Function} string The `toString` result.
     * @returns {Function} Returns `func`.
     */
    var baseSetToString = !defineProperty ? identity : function(func, string) {
      return defineProperty(func, 'toString', {
        'configurable': true,
        'enumerable': false,
        'value': constant(string),
        'writable': true
      });
    };

    /**
     * The base implementation of `_.shuffle`.
     *
     * @private
     * @param {Array|Object} collection The collection to shuffle.
     * @returns {Array} Returns the new shuffled array.
     */
    function baseShuffle(collection) {
      return shuffleSelf(values(collection));
    }

    /**
     * The base implementation of `_.slice` without an iteratee call guard.
     *
     * @private
     * @param {Array} array The array to slice.
     * @param {number} [start=0] The start position.
     * @param {number} [end=array.length] The end position.
     * @returns {Array} Returns the slice of `array`.
     */
    function baseSlice(array, start, end) {
      var index = -1,
          length = array.length;

      if (start < 0) {
        start = -start > length ? 0 : (length + start);
      }
      end = end > length ? length : end;
      if (end < 0) {
        end += length;
      }
      length = start > end ? 0 : ((end - start) >>> 0);
      start >>>= 0;

      var result = Array(length);
      while (++index < length) {
        result[index] = array[index + start];
      }
      return result;
    }

    /**
     * The base implementation of `_.some` without support for iteratee shorthands.
     *
     * @private
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} predicate The function invoked per iteration.
     * @returns {boolean} Returns `true` if any element passes the predicate check,
     *  else `false`.
     */
    function baseSome(collection, predicate) {
      var result;

      baseEach(collection, function(value, index, collection) {
        result = predicate(value, index, collection);
        return !result;
      });
      return !!result;
    }

    /**
     * The base implementation of `_.sortedIndex` and `_.sortedLastIndex` which
     * performs a binary search of `array` to determine the index at which `value`
     * should be inserted into `array` in order to maintain its sort order.
     *
     * @private
     * @param {Array} array The sorted array to inspect.
     * @param {*} value The value to evaluate.
     * @param {boolean} [retHighest] Specify returning the highest qualified index.
     * @returns {number} Returns the index at which `value` should be inserted
     *  into `array`.
     */
    function baseSortedIndex(array, value, retHighest) {
      var low = 0,
          high = array == null ? low : array.length;

      if (typeof value == 'number' && value === value && high <= HALF_MAX_ARRAY_LENGTH) {
        while (low < high) {
          var mid = (low + high) >>> 1,
              computed = array[mid];

          if (computed !== null && !isSymbol(computed) &&
              (retHighest ? (computed <= value) : (computed < value))) {
            low = mid + 1;
          } else {
            high = mid;
          }
        }
        return high;
      }
      return baseSortedIndexBy(array, value, identity, retHighest);
    }

    /**
     * The base implementation of `_.sortedIndexBy` and `_.sortedLastIndexBy`
     * which invokes `iteratee` for `value` and each element of `array` to compute
     * their sort ranking. The iteratee is invoked with one argument; (value).
     *
     * @private
     * @param {Array} array The sorted array to inspect.
     * @param {*} value The value to evaluate.
     * @param {Function} iteratee The iteratee invoked per element.
     * @param {boolean} [retHighest] Specify returning the highest qualified index.
     * @returns {number} Returns the index at which `value` should be inserted
     *  into `array`.
     */
    function baseSortedIndexBy(array, value, iteratee, retHighest) {
      value = iteratee(value);

      var low = 0,
          high = array == null ? 0 : array.length,
          valIsNaN = value !== value,
          valIsNull = value === null,
          valIsSymbol = isSymbol(value),
          valIsUndefined = value === undefined;

      while (low < high) {
        var mid = nativeFloor((low + high) / 2),
            computed = iteratee(array[mid]),
            othIsDefined = computed !== undefined,
            othIsNull = computed === null,
            othIsReflexive = computed === computed,
            othIsSymbol = isSymbol(computed);

        if (valIsNaN) {
          var setLow = retHighest || othIsReflexive;
        } else if (valIsUndefined) {
          setLow = othIsReflexive && (retHighest || othIsDefined);
        } else if (valIsNull) {
          setLow = othIsReflexive && othIsDefined && (retHighest || !othIsNull);
        } else if (valIsSymbol) {
          setLow = othIsReflexive && othIsDefined && !othIsNull && (retHighest || !othIsSymbol);
        } else if (othIsNull || othIsSymbol) {
          setLow = false;
        } else {
          setLow = retHighest ? (computed <= value) : (computed < value);
        }
        if (setLow) {
          low = mid + 1;
        } else {
          high = mid;
        }
      }
      return nativeMin(high, MAX_ARRAY_INDEX);
    }

    /**
     * The base implementation of `_.sortedUniq` and `_.sortedUniqBy` without
     * support for iteratee shorthands.
     *
     * @private
     * @param {Array} array The array to inspect.
     * @param {Function} [iteratee] The iteratee invoked per element.
     * @returns {Array} Returns the new duplicate free array.
     */
    function baseSortedUniq(array, iteratee) {
      var index = -1,
          length = array.length,
          resIndex = 0,
          result = [];

      while (++index < length) {
        var value = array[index],
            computed = iteratee ? iteratee(value) : value;

        if (!index || !eq(computed, seen)) {
          var seen = computed;
          result[resIndex++] = value === 0 ? 0 : value;
        }
      }
      return result;
    }

    /**
     * The base implementation of `_.toNumber` which doesn't ensure correct
     * conversions of binary, hexadecimal, or octal string values.
     *
     * @private
     * @param {*} value The value to process.
     * @returns {number} Returns the number.
     */
    function baseToNumber(value) {
      if (typeof value == 'number') {
        return value;
      }
      if (isSymbol(value)) {
        return NAN;
      }
      return +value;
    }

    /**
     * The base implementation of `_.toString` which doesn't convert nullish
     * values to empty strings.
     *
     * @private
     * @param {*} value The value to process.
     * @returns {string} Returns the string.
     */
    function baseToString(value) {
      // Exit early for strings to avoid a performance hit in some environments.
      if (typeof value == 'string') {
        return value;
      }
      if (isArray(value)) {
        // Recursively convert values (susceptible to call stack limits).
        return arrayMap(value, baseToString) + '';
      }
      if (isSymbol(value)) {
        return symbolToString ? symbolToString.call(value) : '';
      }
      var result = (value + '');
      return (result == '0' && (1 / value) == -INFINITY) ? '-0' : result;
    }

    /**
     * The base implementation of `_.uniqBy` without support for iteratee shorthands.
     *
     * @private
     * @param {Array} array The array to inspect.
     * @param {Function} [iteratee] The iteratee invoked per element.
     * @param {Function} [comparator] The comparator invoked per element.
     * @returns {Array} Returns the new duplicate free array.
     */
    function baseUniq(array, iteratee, comparator) {
      var index = -1,
          includes = arrayIncludes,
          length = array.length,
          isCommon = true,
          result = [],
          seen = result;

      if (comparator) {
        isCommon = false;
        includes = arrayIncludesWith;
      }
      else if (length >= LARGE_ARRAY_SIZE) {
        var set = iteratee ? null : createSet(array);
        if (set) {
          return setToArray(set);
        }
        isCommon = false;
        includes = cacheHas;
        seen = new SetCache;
      }
      else {
        seen = iteratee ? [] : result;
      }
      outer:
      while (++index < length) {
        var value = array[index],
            computed = iteratee ? iteratee(value) : value;

        value = (comparator || value !== 0) ? value : 0;
        if (isCommon && computed === computed) {
          var seenIndex = seen.length;
          while (seenIndex--) {
            if (seen[seenIndex] === computed) {
              continue outer;
            }
          }
          if (iteratee) {
            seen.push(computed);
          }
          result.push(value);
        }
        else if (!includes(seen, computed, comparator)) {
          if (seen !== result) {
            seen.push(computed);
          }
          result.push(value);
        }
      }
      return result;
    }

    /**
     * The base implementation of `_.unset`.
     *
     * @private
     * @param {Object} object The object to modify.
     * @param {Array|string} path The property path to unset.
     * @returns {boolean} Returns `true` if the property is deleted, else `false`.
     */
    function baseUnset(object, path) {
      path = castPath(path, object);
      object = parent(object, path);
      return object == null || delete object[toKey(last(path))];
    }

    /**
     * The base implementation of `_.update`.
     *
     * @private
     * @param {Object} object The object to modify.
     * @param {Array|string} path The path of the property to update.
     * @param {Function} updater The function to produce the updated value.
     * @param {Function} [customizer] The function to customize path creation.
     * @returns {Object} Returns `object`.
     */
    function baseUpdate(object, path, updater, customizer) {
      return baseSet(object, path, updater(baseGet(object, path)), customizer);
    }

    /**
     * The base implementation of methods like `_.dropWhile` and `_.takeWhile`
     * without support for iteratee shorthands.
     *
     * @private
     * @param {Array} array The array to query.
     * @param {Function} predicate The function invoked per iteration.
     * @param {boolean} [isDrop] Specify dropping elements instead of taking them.
     * @param {boolean} [fromRight] Specify iterating from right to left.
     * @returns {Array} Returns the slice of `array`.
     */
    function baseWhile(array, predicate, isDrop, fromRight) {
      var length = array.length,
          index = fromRight ? length : -1;

      while ((fromRight ? index-- : ++index < length) &&
        predicate(array[index], index, array)) {}

      return isDrop
        ? baseSlice(array, (fromRight ? 0 : index), (fromRight ? index + 1 : length))
        : baseSlice(array, (fromRight ? index + 1 : 0), (fromRight ? length : index));
    }

    /**
     * The base implementation of `wrapperValue` which returns the result of
     * performing a sequence of actions on the unwrapped `value`, where each
     * successive action is supplied the return value of the previous.
     *
     * @private
     * @param {*} value The unwrapped value.
     * @param {Array} actions Actions to perform to resolve the unwrapped value.
     * @returns {*} Returns the resolved value.
     */
    function baseWrapperValue(value, actions) {
      var result = value;
      if (result instanceof LazyWrapper) {
        result = result.value();
      }
      return arrayReduce(actions, function(result, action) {
        return action.func.apply(action.thisArg, arrayPush([result], action.args));
      }, result);
    }

    /**
     * The base implementation of methods like `_.xor`, without support for
     * iteratee shorthands, that accepts an array of arrays to inspect.
     *
     * @private
     * @param {Array} arrays The arrays to inspect.
     * @param {Function} [iteratee] The iteratee invoked per element.
     * @param {Function} [comparator] The comparator invoked per element.
     * @returns {Array} Returns the new array of values.
     */
    function baseXor(arrays, iteratee, comparator) {
      var length = arrays.length;
      if (length < 2) {
        return length ? baseUniq(arrays[0]) : [];
      }
      var index = -1,
          result = Array(length);

      while (++index < length) {
        var array = arrays[index],
            othIndex = -1;

        while (++othIndex < length) {
          if (othIndex != index) {
            result[index] = baseDifference(result[index] || array, arrays[othIndex], iteratee, comparator);
          }
        }
      }
      return baseUniq(baseFlatten(result, 1), iteratee, comparator);
    }

    /**
     * This base implementation of `_.zipObject` which assigns values using `assignFunc`.
     *
     * @private
     * @param {Array} props The property identifiers.
     * @param {Array} values The property values.
     * @param {Function} assignFunc The function to assign values.
     * @returns {Object} Returns the new object.
     */
    function baseZipObject(props, values, assignFunc) {
      var index = -1,
          length = props.length,
          valsLength = values.length,
          result = {};

      while (++index < length) {
        var value = index < valsLength ? values[index] : undefined;
        assignFunc(result, props[index], value);
      }
      return result;
    }

    /**
     * Casts `value` to an empty array if it's not an array like object.
     *
     * @private
     * @param {*} value The value to inspect.
     * @returns {Array|Object} Returns the cast array-like object.
     */
    function castArrayLikeObject(value) {
      return isArrayLikeObject(value) ? value : [];
    }

    /**
     * Casts `value` to `identity` if it's not a function.
     *
     * @private
     * @param {*} value The value to inspect.
     * @returns {Function} Returns cast function.
     */
    function castFunction(value) {
      return typeof value == 'function' ? value : identity;
    }

    /**
     * Casts `value` to a path array if it's not one.
     *
     * @private
     * @param {*} value The value to inspect.
     * @param {Object} [object] The object to query keys on.
     * @returns {Array} Returns the cast property path array.
     */
    function castPath(value, object) {
      if (isArray(value)) {
        return value;
      }
      return isKey(value, object) ? [value] : stringToPath(toString(value));
    }

    /**
     * A `baseRest` alias which can be replaced with `identity` by module
     * replacement plugins.
     *
     * @private
     * @type {Function}
     * @param {Function} func The function to apply a rest parameter to.
     * @returns {Function} Returns the new function.
     */
    var castRest = baseRest;

    /**
     * Casts `array` to a slice if it's needed.
     *
     * @private
     * @param {Array} array The array to inspect.
     * @param {number} start The start position.
     * @param {number} [end=array.length] The end position.
     * @returns {Array} Returns the cast slice.
     */
    function castSlice(array, start, end) {
      var length = array.length;
      end = end === undefined ? length : end;
      return (!start && end >= length) ? array : baseSlice(array, start, end);
    }

    /**
     * A simple wrapper around the global [`clearTimeout`](https://mdn.io/clearTimeout).
     *
     * @private
     * @param {number|Object} id The timer id or timeout object of the timer to clear.
     */
    var clearTimeout = ctxClearTimeout || function(id) {
      return root.clearTimeout(id);
    };

    /**
     * Creates a clone of  `buffer`.
     *
     * @private
     * @param {Buffer} buffer The buffer to clone.
     * @param {boolean} [isDeep] Specify a deep clone.
     * @returns {Buffer} Returns the cloned buffer.
     */
    function cloneBuffer(buffer, isDeep) {
      if (isDeep) {
        return buffer.slice();
      }
      var length = buffer.length,
          result = allocUnsafe ? allocUnsafe(length) : new buffer.constructor(length);

      buffer.copy(result);
      return result;
    }

    /**
     * Creates a clone of `arrayBuffer`.
     *
     * @private
     * @param {ArrayBuffer} arrayBuffer The array buffer to clone.
     * @returns {ArrayBuffer} Returns the cloned array buffer.
     */
    function cloneArrayBuffer(arrayBuffer) {
      var result = new arrayBuffer.constructor(arrayBuffer.byteLength);
      new Uint8Array(result).set(new Uint8Array(arrayBuffer));
      return result;
    }

    /**
     * Creates a clone of `dataView`.
     *
     * @private
     * @param {Object} dataView The data view to clone.
     * @param {boolean} [isDeep] Specify a deep clone.
     * @returns {Object} Returns the cloned data view.
     */
    function cloneDataView(dataView, isDeep) {
      var buffer = isDeep ? cloneArrayBuffer(dataView.buffer) : dataView.buffer;
      return new dataView.constructor(buffer, dataView.byteOffset, dataView.byteLength);
    }

    /**
     * Creates a clone of `map`.
     *
     * @private
     * @param {Object} map The map to clone.
     * @param {Function} cloneFunc The function to clone values.
     * @param {boolean} [isDeep] Specify a deep clone.
     * @returns {Object} Returns the cloned map.
     */
    function cloneMap(map, isDeep, cloneFunc) {
      var array = isDeep ? cloneFunc(mapToArray(map), CLONE_DEEP_FLAG) : mapToArray(map);
      return arrayReduce(array, addMapEntry, new map.constructor);
    }

    /**
     * Creates a clone of `regexp`.
     *
     * @private
     * @param {Object} regexp The regexp to clone.
     * @returns {Object} Returns the cloned regexp.
     */
    function cloneRegExp(regexp) {
      var result = new regexp.constructor(regexp.source, reFlags.exec(regexp));
      result.lastIndex = regexp.lastIndex;
      return result;
    }

    /**
     * Creates a clone of `set`.
     *
     * @private
     * @param {Object} set The set to clone.
     * @param {Function} cloneFunc The function to clone values.
     * @param {boolean} [isDeep] Specify a deep clone.
     * @returns {Object} Returns the cloned set.
     */
    function cloneSet(set, isDeep, cloneFunc) {
      var array = isDeep ? cloneFunc(setToArray(set), CLONE_DEEP_FLAG) : setToArray(set);
      return arrayReduce(array, addSetEntry, new set.constructor);
    }

    /**
     * Creates a clone of the `symbol` object.
     *
     * @private
     * @param {Object} symbol The symbol object to clone.
     * @returns {Object} Returns the cloned symbol object.
     */
    function cloneSymbol(symbol) {
      return symbolValueOf ? Object(symbolValueOf.call(symbol)) : {};
    }

    /**
     * Creates a clone of `typedArray`.
     *
     * @private
     * @param {Object} typedArray The typed array to clone.
     * @param {boolean} [isDeep] Specify a deep clone.
     * @returns {Object} Returns the cloned typed array.
     */
    function cloneTypedArray(typedArray, isDeep) {
      var buffer = isDeep ? cloneArrayBuffer(typedArray.buffer) : typedArray.buffer;
      return new typedArray.constructor(buffer, typedArray.byteOffset, typedArray.length);
    }

    /**
     * Compares values to sort them in ascending order.
     *
     * @private
     * @param {*} value The value to compare.
     * @param {*} other The other value to compare.
     * @returns {number} Returns the sort order indicator for `value`.
     */
    function compareAscending(value, other) {
      if (value !== other) {
        var valIsDefined = value !== undefined,
            valIsNull = value === null,
            valIsReflexive = value === value,
            valIsSymbol = isSymbol(value);

        var othIsDefined = other !== undefined,
            othIsNull = other === null,
            othIsReflexive = other === other,
            othIsSymbol = isSymbol(other);

        if ((!othIsNull && !othIsSymbol && !valIsSymbol && value > other) ||
            (valIsSymbol && othIsDefined && othIsReflexive && !othIsNull && !othIsSymbol) ||
            (valIsNull && othIsDefined && othIsReflexive) ||
            (!valIsDefined && othIsReflexive) ||
            !valIsReflexive) {
          return 1;
        }
        if ((!valIsNull && !valIsSymbol && !othIsSymbol && value < other) ||
            (othIsSymbol && valIsDefined && valIsReflexive && !valIsNull && !valIsSymbol) ||
            (othIsNull && valIsDefined && valIsReflexive) ||
            (!othIsDefined && valIsReflexive) ||
            !othIsReflexive) {
          return -1;
        }
      }
      return 0;
    }

    /**
     * Used by `_.orderBy` to compare multiple properties of a value to another
     * and stable sort them.
     *
     * If `orders` is unspecified, all values are sorted in ascending order. Otherwise,
     * specify an order of "desc" for descending or "asc" for ascending sort order
     * of corresponding values.
     *
     * @private
     * @param {Object} object The object to compare.
     * @param {Object} other The other object to compare.
     * @param {boolean[]|string[]} orders The order to sort by for each property.
     * @returns {number} Returns the sort order indicator for `object`.
     */
    function compareMultiple(object, other, orders) {
      var index = -1,
          objCriteria = object.criteria,
          othCriteria = other.criteria,
          length = objCriteria.length,
          ordersLength = orders.length;

      while (++index < length) {
        var result = compareAscending(objCriteria[index], othCriteria[index]);
        if (result) {
          if (index >= ordersLength) {
            return result;
          }
          var order = orders[index];
          return result * (order == 'desc' ? -1 : 1);
        }
      }
      // Fixes an `Array#sort` bug in the JS engine embedded in Adobe applications
      // that causes it, under certain circumstances, to provide the same value for
      // `object` and `other`. See https://github.com/jashkenas/underscore/pull/1247
      // for more details.
      //
      // This also ensures a stable sort in V8 and other engines.
      // See https://bugs.chromium.org/p/v8/issues/detail?id=90 for more details.
      return object.index - other.index;
    }

    /**
     * Creates an array that is the composition of partially applied arguments,
     * placeholders, and provided arguments into a single array of arguments.
     *
     * @private
     * @param {Array} args The provided arguments.
     * @param {Array} partials The arguments to prepend to those provided.
     * @param {Array} holders The `partials` placeholder indexes.
     * @params {boolean} [isCurried] Specify composing for a curried function.
     * @returns {Array} Returns the new array of composed arguments.
     */
    function composeArgs(args, partials, holders, isCurried) {
      var argsIndex = -1,
          argsLength = args.length,
          holdersLength = holders.length,
          leftIndex = -1,
          leftLength = partials.length,
          rangeLength = nativeMax(argsLength - holdersLength, 0),
          result = Array(leftLength + rangeLength),
          isUncurried = !isCurried;

      while (++leftIndex < leftLength) {
        result[leftIndex] = partials[leftIndex];
      }
      while (++argsIndex < holdersLength) {
        if (isUncurried || argsIndex < argsLength) {
          result[holders[argsIndex]] = args[argsIndex];
        }
      }
      while (rangeLength--) {
        result[leftIndex++] = args[argsIndex++];
      }
      return result;
    }

    /**
     * This function is like `composeArgs` except that the arguments composition
     * is tailored for `_.partialRight`.
     *
     * @private
     * @param {Array} args The provided arguments.
     * @param {Array} partials The arguments to append to those provided.
     * @param {Array} holders The `partials` placeholder indexes.
     * @params {boolean} [isCurried] Specify composing for a curried function.
     * @returns {Array} Returns the new array of composed arguments.
     */
    function composeArgsRight(args, partials, holders, isCurried) {
      var argsIndex = -1,
          argsLength = args.length,
          holdersIndex = -1,
          holdersLength = holders.length,
          rightIndex = -1,
          rightLength = partials.length,
          rangeLength = nativeMax(argsLength - holdersLength, 0),
          result = Array(rangeLength + rightLength),
          isUncurried = !isCurried;

      while (++argsIndex < rangeLength) {
        result[argsIndex] = args[argsIndex];
      }
      var offset = argsIndex;
      while (++rightIndex < rightLength) {
        result[offset + rightIndex] = partials[rightIndex];
      }
      while (++holdersIndex < holdersLength) {
        if (isUncurried || argsIndex < argsLength) {
          result[offset + holders[holdersIndex]] = args[argsIndex++];
        }
      }
      return result;
    }

    /**
     * Copies the values of `source` to `array`.
     *
     * @private
     * @param {Array} source The array to copy values from.
     * @param {Array} [array=[]] The array to copy values to.
     * @returns {Array} Returns `array`.
     */
    function copyArray(source, array) {
      var index = -1,
          length = source.length;

      array || (array = Array(length));
      while (++index < length) {
        array[index] = source[index];
      }
      return array;
    }

    /**
     * Copies properties of `source` to `object`.
     *
     * @private
     * @param {Object} source The object to copy properties from.
     * @param {Array} props The property identifiers to copy.
     * @param {Object} [object={}] The object to copy properties to.
     * @param {Function} [customizer] The function to customize copied values.
     * @returns {Object} Returns `object`.
     */
    function copyObject(source, props, object, customizer) {
      var isNew = !object;
      object || (object = {});

      var index = -1,
          length = props.length;

      while (++index < length) {
        var key = props[index];

        var newValue = customizer
          ? customizer(object[key], source[key], key, object, source)
          : undefined;

        if (newValue === undefined) {
          newValue = source[key];
        }
        if (isNew) {
          baseAssignValue(object, key, newValue);
        } else {
          assignValue(object, key, newValue);
        }
      }
      return object;
    }

    /**
     * Copies own symbols of `source` to `object`.
     *
     * @private
     * @param {Object} source The object to copy symbols from.
     * @param {Object} [object={}] The object to copy symbols to.
     * @returns {Object} Returns `object`.
     */
    function copySymbols(source, object) {
      return copyObject(source, getSymbols(source), object);
    }

    /**
     * Copies own and inherited symbols of `source` to `object`.
     *
     * @private
     * @param {Object} source The object to copy symbols from.
     * @param {Object} [object={}] The object to copy symbols to.
     * @returns {Object} Returns `object`.
     */
    function copySymbolsIn(source, object) {
      return copyObject(source, getSymbolsIn(source), object);
    }

    /**
     * Creates a function like `_.groupBy`.
     *
     * @private
     * @param {Function} setter The function to set accumulator values.
     * @param {Function} [initializer] The accumulator object initializer.
     * @returns {Function} Returns the new aggregator function.
     */
    function createAggregator(setter, initializer) {
      return function(collection, iteratee) {
        var func = isArray(collection) ? arrayAggregator : baseAggregator,
            accumulator = initializer ? initializer() : {};

        return func(collection, setter, getIteratee(iteratee, 2), accumulator);
      };
    }

    /**
     * Creates a function like `_.assign`.
     *
     * @private
     * @param {Function} assigner The function to assign values.
     * @returns {Function} Returns the new assigner function.
     */
    function createAssigner(assigner) {
      return baseRest(function(object, sources) {
        var index = -1,
            length = sources.length,
            customizer = length > 1 ? sources[length - 1] : undefined,
            guard = length > 2 ? sources[2] : undefined;

        customizer = (assigner.length > 3 && typeof customizer == 'function')
          ? (length--, customizer)
          : undefined;

        if (guard && isIterateeCall(sources[0], sources[1], guard)) {
          customizer = length < 3 ? undefined : customizer;
          length = 1;
        }
        object = Object(object);
        while (++index < length) {
          var source = sources[index];
          if (source) {
            assigner(object, source, index, customizer);
          }
        }
        return object;
      });
    }

    /**
     * Creates a `baseEach` or `baseEachRight` function.
     *
     * @private
     * @param {Function} eachFunc The function to iterate over a collection.
     * @param {boolean} [fromRight] Specify iterating from right to left.
     * @returns {Function} Returns the new base function.
     */
    function createBaseEach(eachFunc, fromRight) {
      return function(collection, iteratee) {
        if (collection == null) {
          return collection;
        }
        if (!isArrayLike(collection)) {
          return eachFunc(collection, iteratee);
        }
        var length = collection.length,
            index = fromRight ? length : -1,
            iterable = Object(collection);

        while ((fromRight ? index-- : ++index < length)) {
          if (iteratee(iterable[index], index, iterable) === false) {
            break;
          }
        }
        return collection;
      };
    }

    /**
     * Creates a base function for methods like `_.forIn` and `_.forOwn`.
     *
     * @private
     * @param {boolean} [fromRight] Specify iterating from right to left.
     * @returns {Function} Returns the new base function.
     */
    function createBaseFor(fromRight) {
      return function(object, iteratee, keysFunc) {
        var index = -1,
            iterable = Object(object),
            props = keysFunc(object),
            length = props.length;

        while (length--) {
          var key = props[fromRight ? length : ++index];
          if (iteratee(iterable[key], key, iterable) === false) {
            break;
          }
        }
        return object;
      };
    }

    /**
     * Creates a function that wraps `func` to invoke it with the optional `this`
     * binding of `thisArg`.
     *
     * @private
     * @param {Function} func The function to wrap.
     * @param {number} bitmask The bitmask flags. See `createWrap` for more details.
     * @param {*} [thisArg] The `this` binding of `func`.
     * @returns {Function} Returns the new wrapped function.
     */
    function createBind(func, bitmask, thisArg) {
      var isBind = bitmask & WRAP_BIND_FLAG,
          Ctor = createCtor(func);

      function wrapper() {
        var fn = (this && this !== root && this instanceof wrapper) ? Ctor : func;
        return fn.apply(isBind ? thisArg : this, arguments);
      }
      return wrapper;
    }

    /**
     * Creates a function like `_.lowerFirst`.
     *
     * @private
     * @param {string} methodName The name of the `String` case method to use.
     * @returns {Function} Returns the new case function.
     */
    function createCaseFirst(methodName) {
      return function(string) {
        string = toString(string);

        var strSymbols = hasUnicode(string)
          ? stringToArray(string)
          : undefined;

        var chr = strSymbols
          ? strSymbols[0]
          : string.charAt(0);

        var trailing = strSymbols
          ? castSlice(strSymbols, 1).join('')
          : string.slice(1);

        return chr[methodName]() + trailing;
      };
    }

    /**
     * Creates a function like `_.camelCase`.
     *
     * @private
     * @param {Function} callback The function to combine each word.
     * @returns {Function} Returns the new compounder function.
     */
    function createCompounder(callback) {
      return function(string) {
        return arrayReduce(words(deburr(string).replace(reApos, '')), callback, '');
      };
    }

    /**
     * Creates a function that produces an instance of `Ctor` regardless of
     * whether it was invoked as part of a `new` expression or by `call` or `apply`.
     *
     * @private
     * @param {Function} Ctor The constructor to wrap.
     * @returns {Function} Returns the new wrapped function.
     */
    function createCtor(Ctor) {
      return function() {
        // Use a `switch` statement to work with class constructors. See
        // http://ecma-international.org/ecma-262/7.0/#sec-ecmascript-function-objects-call-thisargument-argumentslist
        // for more details.
        var args = arguments;
        switch (args.length) {
          case 0: return new Ctor;
          case 1: return new Ctor(args[0]);
          case 2: return new Ctor(args[0], args[1]);
          case 3: return new Ctor(args[0], args[1], args[2]);
          case 4: return new Ctor(args[0], args[1], args[2], args[3]);
          case 5: return new Ctor(args[0], args[1], args[2], args[3], args[4]);
          case 6: return new Ctor(args[0], args[1], args[2], args[3], args[4], args[5]);
          case 7: return new Ctor(args[0], args[1], args[2], args[3], args[4], args[5], args[6]);
        }
        var thisBinding = baseCreate(Ctor.prototype),
            result = Ctor.apply(thisBinding, args);

        // Mimic the constructor's `return` behavior.
        // See https://es5.github.io/#x13.2.2 for more details.
        return isObject(result) ? result : thisBinding;
      };
    }

    /**
     * Creates a function that wraps `func` to enable currying.
     *
     * @private
     * @param {Function} func The function to wrap.
     * @param {number} bitmask The bitmask flags. See `createWrap` for more details.
     * @param {number} arity The arity of `func`.
     * @returns {Function} Returns the new wrapped function.
     */
    function createCurry(func, bitmask, arity) {
      var Ctor = createCtor(func);

      function wrapper() {
        var length = arguments.length,
            args = Array(length),
            index = length,
            placeholder = getHolder(wrapper);

        while (index--) {
          args[index] = arguments[index];
        }
        var holders = (length < 3 && args[0] !== placeholder && args[length - 1] !== placeholder)
          ? []
          : replaceHolders(args, placeholder);

        length -= holders.length;
        if (length < arity) {
          return createRecurry(
            func, bitmask, createHybrid, wrapper.placeholder, undefined,
            args, holders, undefined, undefined, arity - length);
        }
        var fn = (this && this !== root && this instanceof wrapper) ? Ctor : func;
        return apply(fn, this, args);
      }
      return wrapper;
    }

    /**
     * Creates a `_.find` or `_.findLast` function.
     *
     * @private
     * @param {Function} findIndexFunc The function to find the collection index.
     * @returns {Function} Returns the new find function.
     */
    function createFind(findIndexFunc) {
      return function(collection, predicate, fromIndex) {
        var iterable = Object(collection);
        if (!isArrayLike(collection)) {
          var iteratee = getIteratee(predicate, 3);
          collection = keys(collection);
          predicate = function(key) { return iteratee(iterable[key], key, iterable); };
        }
        var index = findIndexFunc(collection, predicate, fromIndex);
        return index > -1 ? iterable[iteratee ? collection[index] : index] : undefined;
      };
    }

    /**
     * Creates a `_.flow` or `_.flowRight` function.
     *
     * @private
     * @param {boolean} [fromRight] Specify iterating from right to left.
     * @returns {Function} Returns the new flow function.
     */
    function createFlow(fromRight) {
      return flatRest(function(funcs) {
        var length = funcs.length,
            index = length,
            prereq = LodashWrapper.prototype.thru;

        if (fromRight) {
          funcs.reverse();
        }
        while (index--) {
          var func = funcs[index];
          if (typeof func != 'function') {
            throw new TypeError(FUNC_ERROR_TEXT);
          }
          if (prereq && !wrapper && getFuncName(func) == 'wrapper') {
            var wrapper = new LodashWrapper([], true);
          }
        }
        index = wrapper ? index : length;
        while (++index < length) {
          func = funcs[index];

          var funcName = getFuncName(func),
              data = funcName == 'wrapper' ? getData(func) : undefined;

          if (data && isLaziable(data[0]) &&
                data[1] == (WRAP_ARY_FLAG | WRAP_CURRY_FLAG | WRAP_PARTIAL_FLAG | WRAP_REARG_FLAG) &&
                !data[4].length && data[9] == 1
              ) {
            wrapper = wrapper[getFuncName(data[0])].apply(wrapper, data[3]);
          } else {
            wrapper = (func.length == 1 && isLaziable(func))
              ? wrapper[funcName]()
              : wrapper.thru(func);
          }
        }
        return function() {
          var args = arguments,
              value = args[0];

          if (wrapper && args.length == 1 && isArray(value)) {
            return wrapper.plant(value).value();
          }
          var index = 0,
              result = length ? funcs[index].apply(this, args) : value;

          while (++index < length) {
            result = funcs[index].call(this, result);
          }
          return result;
        };
      });
    }

    /**
     * Creates a function that wraps `func` to invoke it with optional `this`
     * binding of `thisArg`, partial application, and currying.
     *
     * @private
     * @param {Function|string} func The function or method name to wrap.
     * @param {number} bitmask The bitmask flags. See `createWrap` for more details.
     * @param {*} [thisArg] The `this` binding of `func`.
     * @param {Array} [partials] The arguments to prepend to those provided to
     *  the new function.
     * @param {Array} [holders] The `partials` placeholder indexes.
     * @param {Array} [partialsRight] The arguments to append to those provided
     *  to the new function.
     * @param {Array} [holdersRight] The `partialsRight` placeholder indexes.
     * @param {Array} [argPos] The argument positions of the new function.
     * @param {number} [ary] The arity cap of `func`.
     * @param {number} [arity] The arity of `func`.
     * @returns {Function} Returns the new wrapped function.
     */
    function createHybrid(func, bitmask, thisArg, partials, holders, partialsRight, holdersRight, argPos, ary, arity) {
      var isAry = bitmask & WRAP_ARY_FLAG,
          isBind = bitmask & WRAP_BIND_FLAG,
          isBindKey = bitmask & WRAP_BIND_KEY_FLAG,
          isCurried = bitmask & (WRAP_CURRY_FLAG | WRAP_CURRY_RIGHT_FLAG),
          isFlip = bitmask & WRAP_FLIP_FLAG,
          Ctor = isBindKey ? undefined : createCtor(func);

      function wrapper() {
        var length = arguments.length,
            args = Array(length),
            index = length;

        while (index--) {
          args[index] = arguments[index];
        }
        if (isCurried) {
          var placeholder = getHolder(wrapper),
              holdersCount = countHolders(args, placeholder);
        }
        if (partials) {
          args = composeArgs(args, partials, holders, isCurried);
        }
        if (partialsRight) {
          args = composeArgsRight(args, partialsRight, holdersRight, isCurried);
        }
        length -= holdersCount;
        if (isCurried && length < arity) {
          var newHolders = replaceHolders(args, placeholder);
          return createRecurry(
            func, bitmask, createHybrid, wrapper.placeholder, thisArg,
            args, newHolders, argPos, ary, arity - length
          );
        }
        var thisBinding = isBind ? thisArg : this,
            fn = isBindKey ? thisBinding[func] : func;

        length = args.length;
        if (argPos) {
          args = reorder(args, argPos);
        } else if (isFlip && length > 1) {
          args.reverse();
        }
        if (isAry && ary < length) {
          args.length = ary;
        }
        if (this && this !== root && this instanceof wrapper) {
          fn = Ctor || createCtor(fn);
        }
        return fn.apply(thisBinding, args);
      }
      return wrapper;
    }

    /**
     * Creates a function like `_.invertBy`.
     *
     * @private
     * @param {Function} setter The function to set accumulator values.
     * @param {Function} toIteratee The function to resolve iteratees.
     * @returns {Function} Returns the new inverter function.
     */
    function createInverter(setter, toIteratee) {
      return function(object, iteratee) {
        return baseInverter(object, setter, toIteratee(iteratee), {});
      };
    }

    /**
     * Creates a function that performs a mathematical operation on two values.
     *
     * @private
     * @param {Function} operator The function to perform the operation.
     * @param {number} [defaultValue] The value used for `undefined` arguments.
     * @returns {Function} Returns the new mathematical operation function.
     */
    function createMathOperation(operator, defaultValue) {
      return function(value, other) {
        var result;
        if (value === undefined && other === undefined) {
          return defaultValue;
        }
        if (value !== undefined) {
          result = value;
        }
        if (other !== undefined) {
          if (result === undefined) {
            return other;
          }
          if (typeof value == 'string' || typeof other == 'string') {
            value = baseToString(value);
            other = baseToString(other);
          } else {
            value = baseToNumber(value);
            other = baseToNumber(other);
          }
          result = operator(value, other);
        }
        return result;
      };
    }

    /**
     * Creates a function like `_.over`.
     *
     * @private
     * @param {Function} arrayFunc The function to iterate over iteratees.
     * @returns {Function} Returns the new over function.
     */
    function createOver(arrayFunc) {
      return flatRest(function(iteratees) {
        iteratees = arrayMap(iteratees, baseUnary(getIteratee()));
        return baseRest(function(args) {
          var thisArg = this;
          return arrayFunc(iteratees, function(iteratee) {
            return apply(iteratee, thisArg, args);
          });
        });
      });
    }

    /**
     * Creates the padding for `string` based on `length`. The `chars` string
     * is truncated if the number of characters exceeds `length`.
     *
     * @private
     * @param {number} length The padding length.
     * @param {string} [chars=' '] The string used as padding.
     * @returns {string} Returns the padding for `string`.
     */
    function createPadding(length, chars) {
      chars = chars === undefined ? ' ' : baseToString(chars);

      var charsLength = chars.length;
      if (charsLength < 2) {
        return charsLength ? baseRepeat(chars, length) : chars;
      }
      var result = baseRepeat(chars, nativeCeil(length / stringSize(chars)));
      return hasUnicode(chars)
        ? castSlice(stringToArray(result), 0, length).join('')
        : result.slice(0, length);
    }

    /**
     * Creates a function that wraps `func` to invoke it with the `this` binding
     * of `thisArg` and `partials` prepended to the arguments it receives.
     *
     * @private
     * @param {Function} func The function to wrap.
     * @param {number} bitmask The bitmask flags. See `createWrap` for more details.
     * @param {*} thisArg The `this` binding of `func`.
     * @param {Array} partials The arguments to prepend to those provided to
     *  the new function.
     * @returns {Function} Returns the new wrapped function.
     */
    function createPartial(func, bitmask, thisArg, partials) {
      var isBind = bitmask & WRAP_BIND_FLAG,
          Ctor = createCtor(func);

      function wrapper() {
        var argsIndex = -1,
            argsLength = arguments.length,
            leftIndex = -1,
            leftLength = partials.length,
            args = Array(leftLength + argsLength),
            fn = (this && this !== root && this instanceof wrapper) ? Ctor : func;

        while (++leftIndex < leftLength) {
          args[leftIndex] = partials[leftIndex];
        }
        while (argsLength--) {
          args[leftIndex++] = arguments[++argsIndex];
        }
        return apply(fn, isBind ? thisArg : this, args);
      }
      return wrapper;
    }

    /**
     * Creates a `_.range` or `_.rangeRight` function.
     *
     * @private
     * @param {boolean} [fromRight] Specify iterating from right to left.
     * @returns {Function} Returns the new range function.
     */
    function createRange(fromRight) {
      return function(start, end, step) {
        if (step && typeof step != 'number' && isIterateeCall(start, end, step)) {
          end = step = undefined;
        }
        // Ensure the sign of `-0` is preserved.
        start = toFinite(start);
        if (end === undefined) {
          end = start;
          start = 0;
        } else {
          end = toFinite(end);
        }
        step = step === undefined ? (start < end ? 1 : -1) : toFinite(step);
        return baseRange(start, end, step, fromRight);
      };
    }

    /**
     * Creates a function that performs a relational operation on two values.
     *
     * @private
     * @param {Function} operator The function to perform the operation.
     * @returns {Function} Returns the new relational operation function.
     */
    function createRelationalOperation(operator) {
      return function(value, other) {
        if (!(typeof value == 'string' && typeof other == 'string')) {
          value = toNumber(value);
          other = toNumber(other);
        }
        return operator(value, other);
      };
    }

    /**
     * Creates a function that wraps `func` to continue currying.
     *
     * @private
     * @param {Function} func The function to wrap.
     * @param {number} bitmask The bitmask flags. See `createWrap` for more details.
     * @param {Function} wrapFunc The function to create the `func` wrapper.
     * @param {*} placeholder The placeholder value.
     * @param {*} [thisArg] The `this` binding of `func`.
     * @param {Array} [partials] The arguments to prepend to those provided to
     *  the new function.
     * @param {Array} [holders] The `partials` placeholder indexes.
     * @param {Array} [argPos] The argument positions of the new function.
     * @param {number} [ary] The arity cap of `func`.
     * @param {number} [arity] The arity of `func`.
     * @returns {Function} Returns the new wrapped function.
     */
    function createRecurry(func, bitmask, wrapFunc, placeholder, thisArg, partials, holders, argPos, ary, arity) {
      var isCurry = bitmask & WRAP_CURRY_FLAG,
          newHolders = isCurry ? holders : undefined,
          newHoldersRight = isCurry ? undefined : holders,
          newPartials = isCurry ? partials : undefined,
          newPartialsRight = isCurry ? undefined : partials;

      bitmask |= (isCurry ? WRAP_PARTIAL_FLAG : WRAP_PARTIAL_RIGHT_FLAG);
      bitmask &= ~(isCurry ? WRAP_PARTIAL_RIGHT_FLAG : WRAP_PARTIAL_FLAG);

      if (!(bitmask & WRAP_CURRY_BOUND_FLAG)) {
        bitmask &= ~(WRAP_BIND_FLAG | WRAP_BIND_KEY_FLAG);
      }
      var newData = [
        func, bitmask, thisArg, newPartials, newHolders, newPartialsRight,
        newHoldersRight, argPos, ary, arity
      ];

      var result = wrapFunc.apply(undefined, newData);
      if (isLaziable(func)) {
        setData(result, newData);
      }
      result.placeholder = placeholder;
      return setWrapToString(result, func, bitmask);
    }

    /**
     * Creates a function like `_.round`.
     *
     * @private
     * @param {string} methodName The name of the `Math` method to use when rounding.
     * @returns {Function} Returns the new round function.
     */
    function createRound(methodName) {
      var func = Math[methodName];
      return function(number, precision) {
        number = toNumber(number);
        precision = precision == null ? 0 : nativeMin(toInteger(precision), 292);
        if (precision) {
          // Shift with exponential notation to avoid floating-point issues.
          // See [MDN](https://mdn.io/round#Examples) for more details.
          var pair = (toString(number) + 'e').split('e'),
              value = func(pair[0] + 'e' + (+pair[1] + precision));

          pair = (toString(value) + 'e').split('e');
          return +(pair[0] + 'e' + (+pair[1] - precision));
        }
        return func(number);
      };
    }

    /**
     * Creates a set object of `values`.
     *
     * @private
     * @param {Array} values The values to add to the set.
     * @returns {Object} Returns the new set.
     */
    var createSet = !(Set && (1 / setToArray(new Set([,-0]))[1]) == INFINITY) ? noop : function(values) {
      return new Set(values);
    };

    /**
     * Creates a `_.toPairs` or `_.toPairsIn` function.
     *
     * @private
     * @param {Function} keysFunc The function to get the keys of a given object.
     * @returns {Function} Returns the new pairs function.
     */
    function createToPairs(keysFunc) {
      return function(object) {
        var tag = getTag(object);
        if (tag == mapTag) {
          return mapToArray(object);
        }
        if (tag == setTag) {
          return setToPairs(object);
        }
        return baseToPairs(object, keysFunc(object));
      };
    }

    /**
     * Creates a function that either curries or invokes `func` with optional
     * `this` binding and partially applied arguments.
     *
     * @private
     * @param {Function|string} func The function or method name to wrap.
     * @param {number} bitmask The bitmask flags.
     *    1 - `_.bind`
     *    2 - `_.bindKey`
     *    4 - `_.curry` or `_.curryRight` of a bound function
     *    8 - `_.curry`
     *   16 - `_.curryRight`
     *   32 - `_.partial`
     *   64 - `_.partialRight`
     *  128 - `_.rearg`
     *  256 - `_.ary`
     *  512 - `_.flip`
     * @param {*} [thisArg] The `this` binding of `func`.
     * @param {Array} [partials] The arguments to be partially applied.
     * @param {Array} [holders] The `partials` placeholder indexes.
     * @param {Array} [argPos] The argument positions of the new function.
     * @param {number} [ary] The arity cap of `func`.
     * @param {number} [arity] The arity of `func`.
     * @returns {Function} Returns the new wrapped function.
     */
    function createWrap(func, bitmask, thisArg, partials, holders, argPos, ary, arity) {
      var isBindKey = bitmask & WRAP_BIND_KEY_FLAG;
      if (!isBindKey && typeof func != 'function') {
        throw new TypeError(FUNC_ERROR_TEXT);
      }
      var length = partials ? partials.length : 0;
      if (!length) {
        bitmask &= ~(WRAP_PARTIAL_FLAG | WRAP_PARTIAL_RIGHT_FLAG);
        partials = holders = undefined;
      }
      ary = ary === undefined ? ary : nativeMax(toInteger(ary), 0);
      arity = arity === undefined ? arity : toInteger(arity);
      length -= holders ? holders.length : 0;

      if (bitmask & WRAP_PARTIAL_RIGHT_FLAG) {
        var partialsRight = partials,
            holdersRight = holders;

        partials = holders = undefined;
      }
      var data = isBindKey ? undefined : getData(func);

      var newData = [
        func, bitmask, thisArg, partials, holders, partialsRight, holdersRight,
        argPos, ary, arity
      ];

      if (data) {
        mergeData(newData, data);
      }
      func = newData[0];
      bitmask = newData[1];
      thisArg = newData[2];
      partials = newData[3];
      holders = newData[4];
      arity = newData[9] = newData[9] === undefined
        ? (isBindKey ? 0 : func.length)
        : nativeMax(newData[9] - length, 0);

      if (!arity && bitmask & (WRAP_CURRY_FLAG | WRAP_CURRY_RIGHT_FLAG)) {
        bitmask &= ~(WRAP_CURRY_FLAG | WRAP_CURRY_RIGHT_FLAG);
      }
      if (!bitmask || bitmask == WRAP_BIND_FLAG) {
        var result = createBind(func, bitmask, thisArg);
      } else if (bitmask == WRAP_CURRY_FLAG || bitmask == WRAP_CURRY_RIGHT_FLAG) {
        result = createCurry(func, bitmask, arity);
      } else if ((bitmask == WRAP_PARTIAL_FLAG || bitmask == (WRAP_BIND_FLAG | WRAP_PARTIAL_FLAG)) && !holders.length) {
        result = createPartial(func, bitmask, thisArg, partials);
      } else {
        result = createHybrid.apply(undefined, newData);
      }
      var setter = data ? baseSetData : setData;
      return setWrapToString(setter(result, newData), func, bitmask);
    }

    /**
     * Used by `_.defaults` to customize its `_.assignIn` use to assign properties
     * of source objects to the destination object for all destination properties
     * that resolve to `undefined`.
     *
     * @private
     * @param {*} objValue The destination value.
     * @param {*} srcValue The source value.
     * @param {string} key The key of the property to assign.
     * @param {Object} object The parent object of `objValue`.
     * @returns {*} Returns the value to assign.
     */
    function customDefaultsAssignIn(objValue, srcValue, key, object) {
      if (objValue === undefined ||
          (eq(objValue, objectProto[key]) && !hasOwnProperty.call(object, key))) {
        return srcValue;
      }
      return objValue;
    }

    /**
     * Used by `_.defaultsDeep` to customize its `_.merge` use to merge source
     * objects into destination objects that are passed thru.
     *
     * @private
     * @param {*} objValue The destination value.
     * @param {*} srcValue The source value.
     * @param {string} key The key of the property to merge.
     * @param {Object} object The parent object of `objValue`.
     * @param {Object} source The parent object of `srcValue`.
     * @param {Object} [stack] Tracks traversed source values and their merged
     *  counterparts.
     * @returns {*} Returns the value to assign.
     */
    function customDefaultsMerge(objValue, srcValue, key, object, source, stack) {
      if (isObject(objValue) && isObject(srcValue)) {
        // Recursively merge objects and arrays (susceptible to call stack limits).
        stack.set(srcValue, objValue);
        baseMerge(objValue, srcValue, undefined, customDefaultsMerge, stack);
        stack['delete'](srcValue);
      }
      return objValue;
    }

    /**
     * Used by `_.omit` to customize its `_.cloneDeep` use to only clone plain
     * objects.
     *
     * @private
     * @param {*} value The value to inspect.
     * @param {string} key The key of the property to inspect.
     * @returns {*} Returns the uncloned value or `undefined` to defer cloning to `_.cloneDeep`.
     */
    function customOmitClone(value) {
      return isPlainObject(value) ? undefined : value;
    }

    /**
     * A specialized version of `baseIsEqualDeep` for arrays with support for
     * partial deep comparisons.
     *
     * @private
     * @param {Array} array The array to compare.
     * @param {Array} other The other array to compare.
     * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details.
     * @param {Function} customizer The function to customize comparisons.
     * @param {Function} equalFunc The function to determine equivalents of values.
     * @param {Object} stack Tracks traversed `array` and `other` objects.
     * @returns {boolean} Returns `true` if the arrays are equivalent, else `false`.
     */
    function equalArrays(array, other, bitmask, customizer, equalFunc, stack) {
      var isPartial = bitmask & COMPARE_PARTIAL_FLAG,
          arrLength = array.length,
          othLength = other.length;

      if (arrLength != othLength && !(isPartial && othLength > arrLength)) {
        return false;
      }
      // Assume cyclic values are equal.
      var stacked = stack.get(array);
      if (stacked && stack.get(other)) {
        return stacked == other;
      }
      var index = -1,
          result = true,
          seen = (bitmask & COMPARE_UNORDERED_FLAG) ? new SetCache : undefined;

      stack.set(array, other);
      stack.set(other, array);

      // Ignore non-index properties.
      while (++index < arrLength) {
        var arrValue = array[index],
            othValue = other[index];

        if (customizer) {
          var compared = isPartial
            ? customizer(othValue, arrValue, index, other, array, stack)
            : customizer(arrValue, othValue, index, array, other, stack);
        }
        if (compared !== undefined) {
          if (compared) {
            continue;
          }
          result = false;
          break;
        }
        // Recursively compare arrays (susceptible to call stack limits).
        if (seen) {
          if (!arraySome(other, function(othValue, othIndex) {
                if (!cacheHas(seen, othIndex) &&
                    (arrValue === othValue || equalFunc(arrValue, othValue, bitmask, customizer, stack))) {
                  return seen.push(othIndex);
                }
              })) {
            result = false;
            break;
          }
        } else if (!(
              arrValue === othValue ||
                equalFunc(arrValue, othValue, bitmask, customizer, stack)
            )) {
          result = false;
          break;
        }
      }
      stack['delete'](array);
      stack['delete'](other);
      return result;
    }

    /**
     * A specialized version of `baseIsEqualDeep` for comparing objects of
     * the same `toStringTag`.
     *
     * **Note:** This function only supports comparing values with tags of
     * `Boolean`, `Date`, `Error`, `Number`, `RegExp`, or `String`.
     *
     * @private
     * @param {Object} object The object to compare.
     * @param {Object} other The other object to compare.
     * @param {string} tag The `toStringTag` of the objects to compare.
     * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details.
     * @param {Function} customizer The function to customize comparisons.
     * @param {Function} equalFunc The function to determine equivalents of values.
     * @param {Object} stack Tracks traversed `object` and `other` objects.
     * @returns {boolean} Returns `true` if the objects are equivalent, else `false`.
     */
    function equalByTag(object, other, tag, bitmask, customizer, equalFunc, stack) {
      switch (tag) {
        case dataViewTag:
          if ((object.byteLength != other.byteLength) ||
              (object.byteOffset != other.byteOffset)) {
            return false;
          }
          object = object.buffer;
          other = other.buffer;

        case arrayBufferTag:
          if ((object.byteLength != other.byteLength) ||
              !equalFunc(new Uint8Array(object), new Uint8Array(other))) {
            return false;
          }
          return true;

        case boolTag:
        case dateTag:
        case numberTag:
          // Coerce booleans to `1` or `0` and dates to milliseconds.
          // Invalid dates are coerced to `NaN`.
          return eq(+object, +other);

        case errorTag:
          return object.name == other.name && object.message == other.message;

        case regexpTag:
        case stringTag:
          // Coerce regexes to strings and treat strings, primitives and objects,
          // as equal. See http://www.ecma-international.org/ecma-262/7.0/#sec-regexp.prototype.tostring
          // for more details.
          return object == (other + '');

        case mapTag:
          var convert = mapToArray;

        case setTag:
          var isPartial = bitmask & COMPARE_PARTIAL_FLAG;
          convert || (convert = setToArray);

          if (object.size != other.size && !isPartial) {
            return false;
          }
          // Assume cyclic values are equal.
          var stacked = stack.get(object);
          if (stacked) {
            return stacked == other;
          }
          bitmask |= COMPARE_UNORDERED_FLAG;

          // Recursively compare objects (susceptible to call stack limits).
          stack.set(object, other);
          var result = equalArrays(convert(object), convert(other), bitmask, customizer, equalFunc, stack);
          stack['delete'](object);
          return result;

        case symbolTag:
          if (symbolValueOf) {
            return symbolValueOf.call(object) == symbolValueOf.call(other);
          }
      }
      return false;
    }

    /**
     * A specialized version of `baseIsEqualDeep` for objects with support for
     * partial deep comparisons.
     *
     * @private
     * @param {Object} object The object to compare.
     * @param {Object} other The other object to compare.
     * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details.
     * @param {Function} customizer The function to customize comparisons.
     * @param {Function} equalFunc The function to determine equivalents of values.
     * @param {Object} stack Tracks traversed `object` and `other` objects.
     * @returns {boolean} Returns `true` if the objects are equivalent, else `false`.
     */
    function equalObjects(object, other, bitmask, customizer, equalFunc, stack) {
      var isPartial = bitmask & COMPARE_PARTIAL_FLAG,
          objProps = getAllKeys(object),
          objLength = objProps.length,
          othProps = getAllKeys(other),
          othLength = othProps.length;

      if (objLength != othLength && !isPartial) {
        return false;
      }
      var index = objLength;
      while (index--) {
        var key = objProps[index];
        if (!(isPartial ? key in other : hasOwnProperty.call(other, key))) {
          return false;
        }
      }
      // Assume cyclic values are equal.
      var stacked = stack.get(object);
      if (stacked && stack.get(other)) {
        return stacked == other;
      }
      var result = true;
      stack.set(object, other);
      stack.set(other, object);

      var skipCtor = isPartial;
      while (++index < objLength) {
        key = objProps[index];
        var objValue = object[key],
            othValue = other[key];

        if (customizer) {
          var compared = isPartial
            ? customizer(othValue, objValue, key, other, object, stack)
            : customizer(objValue, othValue, key, object, other, stack);
        }
        // Recursively compare objects (susceptible to call stack limits).
        if (!(compared === undefined
              ? (objValue === othValue || equalFunc(objValue, othValue, bitmask, customizer, stack))
              : compared
            )) {
          result = false;
          break;
        }
        skipCtor || (skipCtor = key == 'constructor');
      }
      if (result && !skipCtor) {
        var objCtor = object.constructor,
            othCtor = other.constructor;

        // Non `Object` object instances with different constructors are not equal.
        if (objCtor != othCtor &&
            ('constructor' in object && 'constructor' in other) &&
            !(typeof objCtor == 'function' && objCtor instanceof objCtor &&
              typeof othCtor == 'function' && othCtor instanceof othCtor)) {
          result = false;
        }
      }
      stack['delete'](object);
      stack['delete'](other);
      return result;
    }

    /**
     * A specialized version of `baseRest` which flattens the rest array.
     *
     * @private
     * @param {Function} func The function to apply a rest parameter to.
     * @returns {Function} Returns the new function.
     */
    function flatRest(func) {
      return setToString(overRest(func, undefined, flatten), func + '');
    }

    /**
     * Creates an array of own enumerable property names and symbols of `object`.
     *
     * @private
     * @param {Object} object The object to query.
     * @returns {Array} Returns the array of property names and symbols.
     */
    function getAllKeys(object) {
      return baseGetAllKeys(object, keys, getSymbols);
    }

    /**
     * Creates an array of own and inherited enumerable property names and
     * symbols of `object`.
     *
     * @private
     * @param {Object} object The object to query.
     * @returns {Array} Returns the array of property names and symbols.
     */
    function getAllKeysIn(object) {
      return baseGetAllKeys(object, keysIn, getSymbolsIn);
    }

    /**
     * Gets metadata for `func`.
     *
     * @private
     * @param {Function} func The function to query.
     * @returns {*} Returns the metadata for `func`.
     */
    var getData = !metaMap ? noop : function(func) {
      return metaMap.get(func);
    };

    /**
     * Gets the name of `func`.
     *
     * @private
     * @param {Function} func The function to query.
     * @returns {string} Returns the function name.
     */
    function getFuncName(func) {
      var result = (func.name + ''),
          array = realNames[result],
          length = hasOwnProperty.call(realNames, result) ? array.length : 0;

      while (length--) {
        var data = array[length],
            otherFunc = data.func;
        if (otherFunc == null || otherFunc == func) {
          return data.name;
        }
      }
      return result;
    }

    /**
     * Gets the argument placeholder value for `func`.
     *
     * @private
     * @param {Function} func The function to inspect.
     * @returns {*} Returns the placeholder value.
     */
    function getHolder(func) {
      var object = hasOwnProperty.call(lodash, 'placeholder') ? lodash : func;
      return object.placeholder;
    }

    /**
     * Gets the appropriate "iteratee" function. If `_.iteratee` is customized,
     * this function returns the custom method, otherwise it returns `baseIteratee`.
     * If arguments are provided, the chosen function is invoked with them and
     * its result is returned.
     *
     * @private
     * @param {*} [value] The value to convert to an iteratee.
     * @param {number} [arity] The arity of the created iteratee.
     * @returns {Function} Returns the chosen function or its result.
     */
    function getIteratee() {
      var result = lodash.iteratee || iteratee;
      result = result === iteratee ? baseIteratee : result;
      return arguments.length ? result(arguments[0], arguments[1]) : result;
    }

    /**
     * Gets the data for `map`.
     *
     * @private
     * @param {Object} map The map to query.
     * @param {string} key The reference key.
     * @returns {*} Returns the map data.
     */
    function getMapData(map, key) {
      var data = map.__data__;
      return isKeyable(key)
        ? data[typeof key == 'string' ? 'string' : 'hash']
        : data.map;
    }

    /**
     * Gets the property names, values, and compare flags of `object`.
     *
     * @private
     * @param {Object} object The object to query.
     * @returns {Array} Returns the match data of `object`.
     */
    function getMatchData(object) {
      var result = keys(object),
          length = result.length;

      while (length--) {
        var key = result[length],
            value = object[key];

        result[length] = [key, value, isStrictComparable(value)];
      }
      return result;
    }

    /**
     * Gets the native function at `key` of `object`.
     *
     * @private
     * @param {Object} object The object to query.
     * @param {string} key The key of the method to get.
     * @returns {*} Returns the function if it's native, else `undefined`.
     */
    function getNative(object, key) {
      var value = getValue(object, key);
      return baseIsNative(value) ? value : undefined;
    }

    /**
     * A specialized version of `baseGetTag` which ignores `Symbol.toStringTag` values.
     *
     * @private
     * @param {*} value The value to query.
     * @returns {string} Returns the raw `toStringTag`.
     */
    function getRawTag(value) {
      var isOwn = hasOwnProperty.call(value, symToStringTag),
          tag = value[symToStringTag];

      try {
        value[symToStringTag] = undefined;
        var unmasked = true;
      } catch (e) {}

      var result = nativeObjectToString.call(value);
      if (unmasked) {
        if (isOwn) {
          value[symToStringTag] = tag;
        } else {
          delete value[symToStringTag];
        }
      }
      return result;
    }

    /**
     * Creates an array of the own enumerable symbols of `object`.
     *
     * @private
     * @param {Object} object The object to query.
     * @returns {Array} Returns the array of symbols.
     */
    var getSymbols = !nativeGetSymbols ? stubArray : function(object) {
      if (object == null) {
        return [];
      }
      object = Object(object);
      return arrayFilter(nativeGetSymbols(object), function(symbol) {
        return propertyIsEnumerable.call(object, symbol);
      });
    };

    /**
     * Creates an array of the own and inherited enumerable symbols of `object`.
     *
     * @private
     * @param {Object} object The object to query.
     * @returns {Array} Returns the array of symbols.
     */
    var getSymbolsIn = !nativeGetSymbols ? stubArray : function(object) {
      var result = [];
      while (object) {
        arrayPush(result, getSymbols(object));
        object = getPrototype(object);
      }
      return result;
    };

    /**
     * Gets the `toStringTag` of `value`.
     *
     * @private
     * @param {*} value The value to query.
     * @returns {string} Returns the `toStringTag`.
     */
    var getTag = baseGetTag;

    // Fallback for data views, maps, sets, and weak maps in IE 11 and promises in Node.js < 6.
    if ((DataView && getTag(new DataView(new ArrayBuffer(1))) != dataViewTag) ||
        (Map && getTag(new Map) != mapTag) ||
        (Promise && getTag(Promise.resolve()) != promiseTag) ||
        (Set && getTag(new Set) != setTag) ||
        (WeakMap && getTag(new WeakMap) != weakMapTag)) {
      getTag = function(value) {
        var result = baseGetTag(value),
            Ctor = result == objectTag ? value.constructor : undefined,
            ctorString = Ctor ? toSource(Ctor) : '';

        if (ctorString) {
          switch (ctorString) {
            case dataViewCtorString: return dataViewTag;
            case mapCtorString: return mapTag;
            case promiseCtorString: return promiseTag;
            case setCtorString: return setTag;
            case weakMapCtorString: return weakMapTag;
          }
        }
        return result;
      };
    }

    /**
     * Gets the view, applying any `transforms` to the `start` and `end` positions.
     *
     * @private
     * @param {number} start The start of the view.
     * @param {number} end The end of the view.
     * @param {Array} transforms The transformations to apply to the view.
     * @returns {Object} Returns an object containing the `start` and `end`
     *  positions of the view.
     */
    function getView(start, end, transforms) {
      var index = -1,
          length = transforms.length;

      while (++index < length) {
        var data = transforms[index],
            size = data.size;

        switch (data.type) {
          case 'drop':      start += size; break;
          case 'dropRight': end -= size; break;
          case 'take':      end = nativeMin(end, start + size); break;
          case 'takeRight': start = nativeMax(start, end - size); break;
        }
      }
      return { 'start': start, 'end': end };
    }

    /**
     * Extracts wrapper details from the `source` body comment.
     *
     * @private
     * @param {string} source The source to inspect.
     * @returns {Array} Returns the wrapper details.
     */
    function getWrapDetails(source) {
      var match = source.match(reWrapDetails);
      return match ? match[1].split(reSplitDetails) : [];
    }

    /**
     * Checks if `path` exists on `object`.
     *
     * @private
     * @param {Object} object The object to query.
     * @param {Array|string} path The path to check.
     * @param {Function} hasFunc The function to check properties.
     * @returns {boolean} Returns `true` if `path` exists, else `false`.
     */
    function hasPath(object, path, hasFunc) {
      path = castPath(path, object);

      var index = -1,
          length = path.length,
          result = false;

      while (++index < length) {
        var key = toKey(path[index]);
        if (!(result = object != null && hasFunc(object, key))) {
          break;
        }
        object = object[key];
      }
      if (result || ++index != length) {
        return result;
      }
      length = object == null ? 0 : object.length;
      return !!length && isLength(length) && isIndex(key, length) &&
        (isArray(object) || isArguments(object));
    }

    /**
     * Initializes an array clone.
     *
     * @private
     * @param {Array} array The array to clone.
     * @returns {Array} Returns the initialized clone.
     */
    function initCloneArray(array) {
      var length = array.length,
          result = array.constructor(length);

      // Add properties assigned by `RegExp#exec`.
      if (length && typeof array[0] == 'string' && hasOwnProperty.call(array, 'index')) {
        result.index = array.index;
        result.input = array.input;
      }
      return result;
    }

    /**
     * Initializes an object clone.
     *
     * @private
     * @param {Object} object The object to clone.
     * @returns {Object} Returns the initialized clone.
     */
    function initCloneObject(object) {
      return (typeof object.constructor == 'function' && !isPrototype(object))
        ? baseCreate(getPrototype(object))
        : {};
    }

    /**
     * Initializes an object clone based on its `toStringTag`.
     *
     * **Note:** This function only supports cloning values with tags of
     * `Boolean`, `Date`, `Error`, `Number`, `RegExp`, or `String`.
     *
     * @private
     * @param {Object} object The object to clone.
     * @param {string} tag The `toStringTag` of the object to clone.
     * @param {Function} cloneFunc The function to clone values.
     * @param {boolean} [isDeep] Specify a deep clone.
     * @returns {Object} Returns the initialized clone.
     */
    function initCloneByTag(object, tag, cloneFunc, isDeep) {
      var Ctor = object.constructor;
      switch (tag) {
        case arrayBufferTag:
          return cloneArrayBuffer(object);

        case boolTag:
        case dateTag:
          return new Ctor(+object);

        case dataViewTag:
          return cloneDataView(object, isDeep);

        case float32Tag: case float64Tag:
        case int8Tag: case int16Tag: case int32Tag:
        case uint8Tag: case uint8ClampedTag: case uint16Tag: case uint32Tag:
          return cloneTypedArray(object, isDeep);

        case mapTag:
          return cloneMap(object, isDeep, cloneFunc);

        case numberTag:
        case stringTag:
          return new Ctor(object);

        case regexpTag:
          return cloneRegExp(object);

        case setTag:
          return cloneSet(object, isDeep, cloneFunc);

        case symbolTag:
          return cloneSymbol(object);
      }
    }

    /**
     * Inserts wrapper `details` in a comment at the top of the `source` body.
     *
     * @private
     * @param {string} source The source to modify.
     * @returns {Array} details The details to insert.
     * @returns {string} Returns the modified source.
     */
    function insertWrapDetails(source, details) {
      var length = details.length;
      if (!length) {
        return source;
      }
      var lastIndex = length - 1;
      details[lastIndex] = (length > 1 ? '& ' : '') + details[lastIndex];
      details = details.join(length > 2 ? ', ' : ' ');
      return source.replace(reWrapComment, '{\n/* [wrapped with ' + details + '] */\n');
    }

    /**
     * Checks if `value` is a flattenable `arguments` object or array.
     *
     * @private
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is flattenable, else `false`.
     */
    function isFlattenable(value) {
      return isArray(value) || isArguments(value) ||
        !!(spreadableSymbol && value && value[spreadableSymbol]);
    }

    /**
     * Checks if `value` is a valid array-like index.
     *
     * @private
     * @param {*} value The value to check.
     * @param {number} [length=MAX_SAFE_INTEGER] The upper bounds of a valid index.
     * @returns {boolean} Returns `true` if `value` is a valid index, else `false`.
     */
    function isIndex(value, length) {
      length = length == null ? MAX_SAFE_INTEGER : length;
      return !!length &&
        (typeof value == 'number' || reIsUint.test(value)) &&
        (value > -1 && value % 1 == 0 && value < length);
    }

    /**
     * Checks if the given arguments are from an iteratee call.
     *
     * @private
     * @param {*} value The potential iteratee value argument.
     * @param {*} index The potential iteratee index or key argument.
     * @param {*} object The potential iteratee object argument.
     * @returns {boolean} Returns `true` if the arguments are from an iteratee call,
     *  else `false`.
     */
    function isIterateeCall(value, index, object) {
      if (!isObject(object)) {
        return false;
      }
      var type = typeof index;
      if (type == 'number'
            ? (isArrayLike(object) && isIndex(index, object.length))
            : (type == 'string' && index in object)
          ) {
        return eq(object[index], value);
      }
      return false;
    }

    /**
     * Checks if `value` is a property name and not a property path.
     *
     * @private
     * @param {*} value The value to check.
     * @param {Object} [object] The object to query keys on.
     * @returns {boolean} Returns `true` if `value` is a property name, else `false`.
     */
    function isKey(value, object) {
      if (isArray(value)) {
        return false;
      }
      var type = typeof value;
      if (type == 'number' || type == 'symbol' || type == 'boolean' ||
          value == null || isSymbol(value)) {
        return true;
      }
      return reIsPlainProp.test(value) || !reIsDeepProp.test(value) ||
        (object != null && value in Object(object));
    }

    /**
     * Checks if `value` is suitable for use as unique object key.
     *
     * @private
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is suitable, else `false`.
     */
    function isKeyable(value) {
      var type = typeof value;
      return (type == 'string' || type == 'number' || type == 'symbol' || type == 'boolean')
        ? (value !== '__proto__')
        : (value === null);
    }

    /**
     * Checks if `func` has a lazy counterpart.
     *
     * @private
     * @param {Function} func The function to check.
     * @returns {boolean} Returns `true` if `func` has a lazy counterpart,
     *  else `false`.
     */
    function isLaziable(func) {
      var funcName = getFuncName(func),
          other = lodash[funcName];

      if (typeof other != 'function' || !(funcName in LazyWrapper.prototype)) {
        return false;
      }
      if (func === other) {
        return true;
      }
      var data = getData(other);
      return !!data && func === data[0];
    }

    /**
     * Checks if `func` has its source masked.
     *
     * @private
     * @param {Function} func The function to check.
     * @returns {boolean} Returns `true` if `func` is masked, else `false`.
     */
    function isMasked(func) {
      return !!maskSrcKey && (maskSrcKey in func);
    }

    /**
     * Checks if `func` is capable of being masked.
     *
     * @private
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `func` is maskable, else `false`.
     */
    var isMaskable = coreJsData ? isFunction : stubFalse;

    /**
     * Checks if `value` is likely a prototype object.
     *
     * @private
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a prototype, else `false`.
     */
    function isPrototype(value) {
      var Ctor = value && value.constructor,
          proto = (typeof Ctor == 'function' && Ctor.prototype) || objectProto;

      return value === proto;
    }

    /**
     * Checks if `value` is suitable for strict equality comparisons, i.e. `===`.
     *
     * @private
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` if suitable for strict
     *  equality comparisons, else `false`.
     */
    function isStrictComparable(value) {
      return value === value && !isObject(value);
    }

    /**
     * A specialized version of `matchesProperty` for source values suitable
     * for strict equality comparisons, i.e. `===`.
     *
     * @private
     * @param {string} key The key of the property to get.
     * @param {*} srcValue The value to match.
     * @returns {Function} Returns the new spec function.
     */
    function matchesStrictComparable(key, srcValue) {
      return function(object) {
        if (object == null) {
          return false;
        }
        return object[key] === srcValue &&
          (srcValue !== undefined || (key in Object(object)));
      };
    }

    /**
     * A specialized version of `_.memoize` which clears the memoized function's
     * cache when it exceeds `MAX_MEMOIZE_SIZE`.
     *
     * @private
     * @param {Function} func The function to have its output memoized.
     * @returns {Function} Returns the new memoized function.
     */
    function memoizeCapped(func) {
      var result = memoize(func, function(key) {
        if (cache.size === MAX_MEMOIZE_SIZE) {
          cache.clear();
        }
        return key;
      });

      var cache = result.cache;
      return result;
    }

    /**
     * Merges the function metadata of `source` into `data`.
     *
     * Merging metadata reduces the number of wrappers used to invoke a function.
     * This is possible because methods like `_.bind`, `_.curry`, and `_.partial`
     * may be applied regardless of execution order. Methods like `_.ary` and
     * `_.rearg` modify function arguments, making the order in which they are
     * executed important, preventing the merging of metadata. However, we make
     * an exception for a safe combined case where curried functions have `_.ary`
     * and or `_.rearg` applied.
     *
     * @private
     * @param {Array} data The destination metadata.
     * @param {Array} source The source metadata.
     * @returns {Array} Returns `data`.
     */
    function mergeData(data, source) {
      var bitmask = data[1],
          srcBitmask = source[1],
          newBitmask = bitmask | srcBitmask,
          isCommon = newBitmask < (WRAP_BIND_FLAG | WRAP_BIND_KEY_FLAG | WRAP_ARY_FLAG);

      var isCombo =
        ((srcBitmask == WRAP_ARY_FLAG) && (bitmask == WRAP_CURRY_FLAG)) ||
        ((srcBitmask == WRAP_ARY_FLAG) && (bitmask == WRAP_REARG_FLAG) && (data[7].length <= source[8])) ||
        ((srcBitmask == (WRAP_ARY_FLAG | WRAP_REARG_FLAG)) && (source[7].length <= source[8]) && (bitmask == WRAP_CURRY_FLAG));

      // Exit early if metadata can't be merged.
      if (!(isCommon || isCombo)) {
        return data;
      }
      // Use source `thisArg` if available.
      if (srcBitmask & WRAP_BIND_FLAG) {
        data[2] = source[2];
        // Set when currying a bound function.
        newBitmask |= bitmask & WRAP_BIND_FLAG ? 0 : WRAP_CURRY_BOUND_FLAG;
      }
      // Compose partial arguments.
      var value = source[3];
      if (value) {
        var partials = data[3];
        data[3] = partials ? composeArgs(partials, value, source[4]) : value;
        data[4] = partials ? replaceHolders(data[3], PLACEHOLDER) : source[4];
      }
      // Compose partial right arguments.
      value = source[5];
      if (value) {
        partials = data[5];
        data[5] = partials ? composeArgsRight(partials, value, source[6]) : value;
        data[6] = partials ? replaceHolders(data[5], PLACEHOLDER) : source[6];
      }
      // Use source `argPos` if available.
      value = source[7];
      if (value) {
        data[7] = value;
      }
      // Use source `ary` if it's smaller.
      if (srcBitmask & WRAP_ARY_FLAG) {
        data[8] = data[8] == null ? source[8] : nativeMin(data[8], source[8]);
      }
      // Use source `arity` if one is not provided.
      if (data[9] == null) {
        data[9] = source[9];
      }
      // Use source `func` and merge bitmasks.
      data[0] = source[0];
      data[1] = newBitmask;

      return data;
    }

    /**
     * This function is like
     * [`Object.keys`](http://ecma-international.org/ecma-262/7.0/#sec-object.keys)
     * except that it includes inherited enumerable properties.
     *
     * @private
     * @param {Object} object The object to query.
     * @returns {Array} Returns the array of property names.
     */
    function nativeKeysIn(object) {
      var result = [];
      if (object != null) {
        for (var key in Object(object)) {
          result.push(key);
        }
      }
      return result;
    }

    /**
     * Converts `value` to a string using `Object.prototype.toString`.
     *
     * @private
     * @param {*} value The value to convert.
     * @returns {string} Returns the converted string.
     */
    function objectToString(value) {
      return nativeObjectToString.call(value);
    }

    /**
     * A specialized version of `baseRest` which transforms the rest array.
     *
     * @private
     * @param {Function} func The function to apply a rest parameter to.
     * @param {number} [start=func.length-1] The start position of the rest parameter.
     * @param {Function} transform The rest array transform.
     * @returns {Function} Returns the new function.
     */
    function overRest(func, start, transform) {
      start = nativeMax(start === undefined ? (func.length - 1) : start, 0);
      return function() {
        var args = arguments,
            index = -1,
            length = nativeMax(args.length - start, 0),
            array = Array(length);

        while (++index < length) {
          array[index] = args[start + index];
        }
        index = -1;
        var otherArgs = Array(start + 1);
        while (++index < start) {
          otherArgs[index] = args[index];
        }
        otherArgs[start] = transform(array);
        return apply(func, this, otherArgs);
      };
    }

    /**
     * Gets the parent value at `path` of `object`.
     *
     * @private
     * @param {Object} object The object to query.
     * @param {Array} path The path to get the parent value of.
     * @returns {*} Returns the parent value.
     */
    function parent(object, path) {
      return path.length < 2 ? object : baseGet(object, baseSlice(path, 0, -1));
    }

    /**
     * Reorder `array` according to the specified indexes where the element at
     * the first index is assigned as the first element, the element at
     * the second index is assigned as the second element, and so on.
     *
     * @private
     * @param {Array} array The array to reorder.
     * @param {Array} indexes The arranged array indexes.
     * @returns {Array} Returns `array`.
     */
    function reorder(array, indexes) {
      var arrLength = array.length,
          length = nativeMin(indexes.length, arrLength),
          oldArray = copyArray(array);

      while (length--) {
        var index = indexes[length];
        array[length] = isIndex(index, arrLength) ? oldArray[index] : undefined;
      }
      return array;
    }

    /**
     * Sets metadata for `func`.
     *
     * **Note:** If this function becomes hot, i.e. is invoked a lot in a short
     * period of time, it will trip its breaker and transition to an identity
     * function to avoid garbage collection pauses in V8. See
     * [V8 issue 2070](https://bugs.chromium.org/p/v8/issues/detail?id=2070)
     * for more details.
     *
     * @private
     * @param {Function} func The function to associate metadata with.
     * @param {*} data The metadata.
     * @returns {Function} Returns `func`.
     */
    var setData = shortOut(baseSetData);

    /**
     * A simple wrapper around the global [`setTimeout`](https://mdn.io/setTimeout).
     *
     * @private
     * @param {Function} func The function to delay.
     * @param {number} wait The number of milliseconds to delay invocation.
     * @returns {number|Object} Returns the timer id or timeout object.
     */
    var setTimeout = ctxSetTimeout || function(func, wait) {
      return root.setTimeout(func, wait);
    };

    /**
     * Sets the `toString` method of `func` to return `string`.
     *
     * @private
     * @param {Function} func The function to modify.
     * @param {Function} string The `toString` result.
     * @returns {Function} Returns `func`.
     */
    var setToString = shortOut(baseSetToString);

    /**
     * Sets the `toString` method of `wrapper` to mimic the source of `reference`
     * with wrapper details in a comment at the top of the source body.
     *
     * @private
     * @param {Function} wrapper The function to modify.
     * @param {Function} reference The reference function.
     * @param {number} bitmask The bitmask flags. See `createWrap` for more details.
     * @returns {Function} Returns `wrapper`.
     */
    function setWrapToString(wrapper, reference, bitmask) {
      var source = (reference + '');
      return setToString(wrapper, insertWrapDetails(source, updateWrapDetails(getWrapDetails(source), bitmask)));
    }

    /**
     * Creates a function that'll short out and invoke `identity` instead
     * of `func` when it's called `HOT_COUNT` or more times in `HOT_SPAN`
     * milliseconds.
     *
     * @private
     * @param {Function} func The function to restrict.
     * @returns {Function} Returns the new shortable function.
     */
    function shortOut(func) {
      var count = 0,
          lastCalled = 0;

      return function() {
        var stamp = nativeNow(),
            remaining = HOT_SPAN - (stamp - lastCalled);

        lastCalled = stamp;
        if (remaining > 0) {
          if (++count >= HOT_COUNT) {
            return arguments[0];
          }
        } else {
          count = 0;
        }
        return func.apply(undefined, arguments);
      };
    }

    /**
     * A specialized version of `_.shuffle` which mutates and sets the size of `array`.
     *
     * @private
     * @param {Array} array The array to shuffle.
     * @param {number} [size=array.length] The size of `array`.
     * @returns {Array} Returns `array`.
     */
    function shuffleSelf(array, size) {
      var index = -1,
          length = array.length,
          lastIndex = length - 1;

      size = size === undefined ? length : size;
      while (++index < size) {
        var rand = baseRandom(index, lastIndex),
            value = array[rand];

        array[rand] = array[index];
        array[index] = value;
      }
      array.length = size;
      return array;
    }

    /**
     * Converts `string` to a property path array.
     *
     * @private
     * @param {string} string The string to convert.
     * @returns {Array} Returns the property path array.
     */
    var stringToPath = memoizeCapped(function(string) {
      var result = [];
      if (reLeadingDot.test(string)) {
        result.push('');
      }
      string.replace(rePropName, function(match, number, quote, string) {
        result.push(quote ? string.replace(reEscapeChar, '$1') : (number || match));
      });
      return result;
    });

    /**
     * Converts `value` to a string key if it's not a string or symbol.
     *
     * @private
     * @param {*} value The value to inspect.
     * @returns {string|symbol} Returns the key.
     */
    function toKey(value) {
      if (typeof value == 'string' || isSymbol(value)) {
        return value;
      }
      var result = (value + '');
      return (result == '0' && (1 / value) == -INFINITY) ? '-0' : result;
    }

    /**
     * Converts `func` to its source code.
     *
     * @private
     * @param {Function} func The function to convert.
     * @returns {string} Returns the source code.
     */
    function toSource(func) {
      if (func != null) {
        try {
          return funcToString.call(func);
        } catch (e) {}
        try {
          return (func + '');
        } catch (e) {}
      }
      return '';
    }

    /**
     * Updates wrapper `details` based on `bitmask` flags.
     *
     * @private
     * @returns {Array} details The details to modify.
     * @param {number} bitmask The bitmask flags. See `createWrap` for more details.
     * @returns {Array} Returns `details`.
     */
    function updateWrapDetails(details, bitmask) {
      arrayEach(wrapFlags, function(pair) {
        var value = '_.' + pair[0];
        if ((bitmask & pair[1]) && !arrayIncludes(details, value)) {
          details.push(value);
        }
      });
      return details.sort();
    }

    /**
     * Creates a clone of `wrapper`.
     *
     * @private
     * @param {Object} wrapper The wrapper to clone.
     * @returns {Object} Returns the cloned wrapper.
     */
    function wrapperClone(wrapper) {
      if (wrapper instanceof LazyWrapper) {
        return wrapper.clone();
      }
      var result = new LodashWrapper(wrapper.__wrapped__, wrapper.__chain__);
      result.__actions__ = copyArray(wrapper.__actions__);
      result.__index__  = wrapper.__index__;
      result.__values__ = wrapper.__values__;
      return result;
    }

    /*------------------------------------------------------------------------*/

    /**
     * Creates an array of elements split into groups the length of `size`.
     * If `array` can't be split evenly, the final chunk will be the remaining
     * elements.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Array
     * @param {Array} array The array to process.
     * @param {number} [size=1] The length of each chunk
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
     * @returns {Array} Returns the new array of chunks.
     * @example
     *
     * _.chunk(['a', 'b', 'c', 'd'], 2);
     * // => [['a', 'b'], ['c', 'd']]
     *
     * _.chunk(['a', 'b', 'c', 'd'], 3);
     * // => [['a', 'b', 'c'], ['d']]
     */
    function chunk(array, size, guard) {
      if ((guard ? isIterateeCall(array, size, guard) : size === undefined)) {
        size = 1;
      } else {
        size = nativeMax(toInteger(size), 0);
      }
      var length = array == null ? 0 : array.length;
      if (!length || size < 1) {
        return [];
      }
      var index = 0,
          resIndex = 0,
          result = Array(nativeCeil(length / size));

      while (index < length) {
        result[resIndex++] = baseSlice(array, index, (index += size));
      }
      return result;
    }

    /**
     * Creates an array with all falsey values removed. The values `false`, `null`,
     * `0`, `""`, `undefined`, and `NaN` are falsey.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Array
     * @param {Array} array The array to compact.
     * @returns {Array} Returns the new array of filtered values.
     * @example
     *
     * _.compact([0, 1, false, 2, '', 3]);
     * // => [1, 2, 3]
     */
    function compact(array) {
      var index = -1,
          length = array == null ? 0 : array.length,
          resIndex = 0,
          result = [];

      while (++index < length) {
        var value = array[index];
        if (value) {
          result[resIndex++] = value;
        }
      }
      return result;
    }

    /**
     * Creates a new array concatenating `array` with any additional arrays
     * and/or values.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {Array} array The array to concatenate.
     * @param {...*} [values] The values to concatenate.
     * @returns {Array} Returns the new concatenated array.
     * @example
     *
     * var array = [1];
     * var other = _.concat(array, 2, [3], [[4]]);
     *
     * console.log(other);
     * // => [1, 2, 3, [4]]
     *
     * console.log(array);
     * // => [1]
     */
    function concat() {
      var length = arguments.length;
      if (!length) {
        return [];
      }
      var args = Array(length - 1),
          array = arguments[0],
          index = length;

      while (index--) {
        args[index - 1] = arguments[index];
      }
      return arrayPush(isArray(array) ? copyArray(array) : [array], baseFlatten(args, 1));
    }

    /**
     * Creates an array of `array` values not included in the other given arrays
     * using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
     * for equality comparisons. The order and references of result values are
     * determined by the first array.
     *
     * **Note:** Unlike `_.pullAll`, this method returns a new array.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Array
     * @param {Array} array The array to inspect.
     * @param {...Array} [values] The values to exclude.
     * @returns {Array} Returns the new array of filtered values.
     * @see _.without, _.xor
     * @example
     *
     * _.difference([2, 1], [2, 3]);
     * // => [1]
     */
    var difference = baseRest(function(array, values) {
      return isArrayLikeObject(array)
        ? baseDifference(array, baseFlatten(values, 1, isArrayLikeObject, true))
        : [];
    });

    /**
     * This method is like `_.difference` except that it accepts `iteratee` which
     * is invoked for each element of `array` and `values` to generate the criterion
     * by which they're compared. The order and references of result values are
     * determined by the first array. The iteratee is invoked with one argument:
     * (value).
     *
     * **Note:** Unlike `_.pullAllBy`, this method returns a new array.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {Array} array The array to inspect.
     * @param {...Array} [values] The values to exclude.
     * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
     * @returns {Array} Returns the new array of filtered values.
     * @example
     *
     * _.differenceBy([2.1, 1.2], [2.3, 3.4], Math.floor);
     * // => [1.2]
     *
     * // The `_.property` iteratee shorthand.
     * _.differenceBy([{ 'x': 2 }, { 'x': 1 }], [{ 'x': 1 }], 'x');
     * // => [{ 'x': 2 }]
     */
    var differenceBy = baseRest(function(array, values) {
      var iteratee = last(values);
      if (isArrayLikeObject(iteratee)) {
        iteratee = undefined;
      }
      return isArrayLikeObject(array)
        ? baseDifference(array, baseFlatten(values, 1, isArrayLikeObject, true), getIteratee(iteratee, 2))
        : [];
    });

    /**
     * This method is like `_.difference` except that it accepts `comparator`
     * which is invoked to compare elements of `array` to `values`. The order and
     * references of result values are determined by the first array. The comparator
     * is invoked with two arguments: (arrVal, othVal).
     *
     * **Note:** Unlike `_.pullAllWith`, this method returns a new array.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {Array} array The array to inspect.
     * @param {...Array} [values] The values to exclude.
     * @param {Function} [comparator] The comparator invoked per element.
     * @returns {Array} Returns the new array of filtered values.
     * @example
     *
     * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }];
     *
     * _.differenceWith(objects, [{ 'x': 1, 'y': 2 }], _.isEqual);
     * // => [{ 'x': 2, 'y': 1 }]
     */
    var differenceWith = baseRest(function(array, values) {
      var comparator = last(values);
      if (isArrayLikeObject(comparator)) {
        comparator = undefined;
      }
      return isArrayLikeObject(array)
        ? baseDifference(array, baseFlatten(values, 1, isArrayLikeObject, true), undefined, comparator)
        : [];
    });

    /**
     * Creates a slice of `array` with `n` elements dropped from the beginning.
     *
     * @static
     * @memberOf _
     * @since 0.5.0
     * @category Array
     * @param {Array} array The array to query.
     * @param {number} [n=1] The number of elements to drop.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
     * @returns {Array} Returns the slice of `array`.
     * @example
     *
     * _.drop([1, 2, 3]);
     * // => [2, 3]
     *
     * _.drop([1, 2, 3], 2);
     * // => [3]
     *
     * _.drop([1, 2, 3], 5);
     * // => []
     *
     * _.drop([1, 2, 3], 0);
     * // => [1, 2, 3]
     */
    function drop(array, n, guard) {
      var length = array == null ? 0 : array.length;
      if (!length) {
        return [];
      }
      n = (guard || n === undefined) ? 1 : toInteger(n);
      return baseSlice(array, n < 0 ? 0 : n, length);
    }

    /**
     * Creates a slice of `array` with `n` elements dropped from the end.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Array
     * @param {Array} array The array to query.
     * @param {number} [n=1] The number of elements to drop.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
     * @returns {Array} Returns the slice of `array`.
     * @example
     *
     * _.dropRight([1, 2, 3]);
     * // => [1, 2]
     *
     * _.dropRight([1, 2, 3], 2);
     * // => [1]
     *
     * _.dropRight([1, 2, 3], 5);
     * // => []
     *
     * _.dropRight([1, 2, 3], 0);
     * // => [1, 2, 3]
     */
    function dropRight(array, n, guard) {
      var length = array == null ? 0 : array.length;
      if (!length) {
        return [];
      }
      n = (guard || n === undefined) ? 1 : toInteger(n);
      n = length - n;
      return baseSlice(array, 0, n < 0 ? 0 : n);
    }

    /**
     * Creates a slice of `array` excluding elements dropped from the end.
     * Elements are dropped until `predicate` returns falsey. The predicate is
     * invoked with three arguments: (value, index, array).
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Array
     * @param {Array} array The array to query.
     * @param {Function} [predicate=_.identity] The function invoked per iteration.
     * @returns {Array} Returns the slice of `array`.
     * @example
     *
     * var users = [
     *   { 'user': 'barney',  'active': true },
     *   { 'user': 'fred',    'active': false },
     *   { 'user': 'pebbles', 'active': false }
     * ];
     *
     * _.dropRightWhile(users, function(o) { return !o.active; });
     * // => objects for ['barney']
     *
     * // The `_.matches` iteratee shorthand.
     * _.dropRightWhile(users, { 'user': 'pebbles', 'active': false });
     * // => objects for ['barney', 'fred']
     *
     * // The `_.matchesProperty` iteratee shorthand.
     * _.dropRightWhile(users, ['active', false]);
     * // => objects for ['barney']
     *
     * // The `_.property` iteratee shorthand.
     * _.dropRightWhile(users, 'active');
     * // => objects for ['barney', 'fred', 'pebbles']
     */
    function dropRightWhile(array, predicate) {
      return (array && array.length)
        ? baseWhile(array, getIteratee(predicate, 3), true, true)
        : [];
    }

    /**
     * Creates a slice of `array` excluding elements dropped from the beginning.
     * Elements are dropped until `predicate` returns falsey. The predicate is
     * invoked with three arguments: (value, index, array).
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Array
     * @param {Array} array The array to query.
     * @param {Function} [predicate=_.identity] The function invoked per iteration.
     * @returns {Array} Returns the slice of `array`.
     * @example
     *
     * var users = [
     *   { 'user': 'barney',  'active': false },
     *   { 'user': 'fred',    'active': false },
     *   { 'user': 'pebbles', 'active': true }
     * ];
     *
     * _.dropWhile(users, function(o) { return !o.active; });
     * // => objects for ['pebbles']
     *
     * // The `_.matches` iteratee shorthand.
     * _.dropWhile(users, { 'user': 'barney', 'active': false });
     * // => objects for ['fred', 'pebbles']
     *
     * // The `_.matchesProperty` iteratee shorthand.
     * _.dropWhile(users, ['active', false]);
     * // => objects for ['pebbles']
     *
     * // The `_.property` iteratee shorthand.
     * _.dropWhile(users, 'active');
     * // => objects for ['barney', 'fred', 'pebbles']
     */
    function dropWhile(array, predicate) {
      return (array && array.length)
        ? baseWhile(array, getIteratee(predicate, 3), true)
        : [];
    }

    /**
     * Fills elements of `array` with `value` from `start` up to, but not
     * including, `end`.
     *
     * **Note:** This method mutates `array`.
     *
     * @static
     * @memberOf _
     * @since 3.2.0
     * @category Array
     * @param {Array} array The array to fill.
     * @param {*} value The value to fill `array` with.
     * @param {number} [start=0] The start position.
     * @param {number} [end=array.length] The end position.
     * @returns {Array} Returns `array`.
     * @example
     *
     * var array = [1, 2, 3];
     *
     * _.fill(array, 'a');
     * console.log(array);
     * // => ['a', 'a', 'a']
     *
     * _.fill(Array(3), 2);
     * // => [2, 2, 2]
     *
     * _.fill([4, 6, 8, 10], '*', 1, 3);
     * // => [4, '*', '*', 10]
     */
    function fill(array, value, start, end) {
      var length = array == null ? 0 : array.length;
      if (!length) {
        return [];
      }
      if (start && typeof start != 'number' && isIterateeCall(array, value, start)) {
        start = 0;
        end = length;
      }
      return baseFill(array, value, start, end);
    }

    /**
     * This method is like `_.find` except that it returns the index of the first
     * element `predicate` returns truthy for instead of the element itself.
     *
     * @static
     * @memberOf _
     * @since 1.1.0
     * @category Array
     * @param {Array} array The array to inspect.
     * @param {Function} [predicate=_.identity] The function invoked per iteration.
     * @param {number} [fromIndex=0] The index to search from.
     * @returns {number} Returns the index of the found element, else `-1`.
     * @example
     *
     * var users = [
     *   { 'user': 'barney',  'active': false },
     *   { 'user': 'fred',    'active': false },
     *   { 'user': 'pebbles', 'active': true }
     * ];
     *
     * _.findIndex(users, function(o) { return o.user == 'barney'; });
     * // => 0
     *
     * // The `_.matches` iteratee shorthand.
     * _.findIndex(users, { 'user': 'fred', 'active': false });
     * // => 1
     *
     * // The `_.matchesProperty` iteratee shorthand.
     * _.findIndex(users, ['active', false]);
     * // => 0
     *
     * // The `_.property` iteratee shorthand.
     * _.findIndex(users, 'active');
     * // => 2
     */
    function findIndex(array, predicate, fromIndex) {
      var length = array == null ? 0 : array.length;
      if (!length) {
        return -1;
      }
      var index = fromIndex == null ? 0 : toInteger(fromIndex);
      if (index < 0) {
        index = nativeMax(length + index, 0);
      }
      return baseFindIndex(array, getIteratee(predicate, 3), index);
    }

    /**
     * This method is like `_.findIndex` except that it iterates over elements
     * of `collection` from right to left.
     *
     * @static
     * @memberOf _
     * @since 2.0.0
     * @category Array
     * @param {Array} array The array to inspect.
     * @param {Function} [predicate=_.identity] The function invoked per iteration.
     * @param {number} [fromIndex=array.length-1] The index to search from.
     * @returns {number} Returns the index of the found element, else `-1`.
     * @example
     *
     * var users = [
     *   { 'user': 'barney',  'active': true },
     *   { 'user': 'fred',    'active': false },
     *   { 'user': 'pebbles', 'active': false }
     * ];
     *
     * _.findLastIndex(users, function(o) { return o.user == 'pebbles'; });
     * // => 2
     *
     * // The `_.matches` iteratee shorthand.
     * _.findLastIndex(users, { 'user': 'barney', 'active': true });
     * // => 0
     *
     * // The `_.matchesProperty` iteratee shorthand.
     * _.findLastIndex(users, ['active', false]);
     * // => 2
     *
     * // The `_.property` iteratee shorthand.
     * _.findLastIndex(users, 'active');
     * // => 0
     */
    function findLastIndex(array, predicate, fromIndex) {
      var length = array == null ? 0 : array.length;
      if (!length) {
        return -1;
      }
      var index = length - 1;
      if (fromIndex !== undefined) {
        index = toInteger(fromIndex);
        index = fromIndex < 0
          ? nativeMax(length + index, 0)
          : nativeMin(index, length - 1);
      }
      return baseFindIndex(array, getIteratee(predicate, 3), index, true);
    }

    /**
     * Flattens `array` a single level deep.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Array
     * @param {Array} array The array to flatten.
     * @returns {Array} Returns the new flattened array.
     * @example
     *
     * _.flatten([1, [2, [3, [4]], 5]]);
     * // => [1, 2, [3, [4]], 5]
     */
    function flatten(array) {
      var length = array == null ? 0 : array.length;
      return length ? baseFlatten(array, 1) : [];
    }

    /**
     * Recursively flattens `array`.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Array
     * @param {Array} array The array to flatten.
     * @returns {Array} Returns the new flattened array.
     * @example
     *
     * _.flattenDeep([1, [2, [3, [4]], 5]]);
     * // => [1, 2, 3, 4, 5]
     */
    function flattenDeep(array) {
      var length = array == null ? 0 : array.length;
      return length ? baseFlatten(array, INFINITY) : [];
    }

    /**
     * Recursively flatten `array` up to `depth` times.
     *
     * @static
     * @memberOf _
     * @since 4.4.0
     * @category Array
     * @param {Array} array The array to flatten.
     * @param {number} [depth=1] The maximum recursion depth.
     * @returns {Array} Returns the new flattened array.
     * @example
     *
     * var array = [1, [2, [3, [4]], 5]];
     *
     * _.flattenDepth(array, 1);
     * // => [1, 2, [3, [4]], 5]
     *
     * _.flattenDepth(array, 2);
     * // => [1, 2, 3, [4], 5]
     */
    function flattenDepth(array, depth) {
      var length = array == null ? 0 : array.length;
      if (!length) {
        return [];
      }
      depth = depth === undefined ? 1 : toInteger(depth);
      return baseFlatten(array, depth);
    }

    /**
     * The inverse of `_.toPairs`; this method returns an object composed
     * from key-value `pairs`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {Array} pairs The key-value pairs.
     * @returns {Object} Returns the new object.
     * @example
     *
     * _.fromPairs([['a', 1], ['b', 2]]);
     * // => { 'a': 1, 'b': 2 }
     */
    function fromPairs(pairs) {
      var index = -1,
          length = pairs == null ? 0 : pairs.length,
          result = {};

      while (++index < length) {
        var pair = pairs[index];
        result[pair[0]] = pair[1];
      }
      return result;
    }

    /**
     * Gets the first element of `array`.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @alias first
     * @category Array
     * @param {Array} array The array to query.
     * @returns {*} Returns the first element of `array`.
     * @example
     *
     * _.head([1, 2, 3]);
     * // => 1
     *
     * _.head([]);
     * // => undefined
     */
    function head(array) {
      return (array && array.length) ? array[0] : undefined;
    }

    /**
     * Gets the index at which the first occurrence of `value` is found in `array`
     * using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
     * for equality comparisons. If `fromIndex` is negative, it's used as the
     * offset from the end of `array`.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Array
     * @param {Array} array The array to inspect.
     * @param {*} value The value to search for.
     * @param {number} [fromIndex=0] The index to search from.
     * @returns {number} Returns the index of the matched value, else `-1`.
     * @example
     *
     * _.indexOf([1, 2, 1, 2], 2);
     * // => 1
     *
     * // Search from the `fromIndex`.
     * _.indexOf([1, 2, 1, 2], 2, 2);
     * // => 3
     */
    function indexOf(array, value, fromIndex) {
      var length = array == null ? 0 : array.length;
      if (!length) {
        return -1;
      }
      var index = fromIndex == null ? 0 : toInteger(fromIndex);
      if (index < 0) {
        index = nativeMax(length + index, 0);
      }
      return baseIndexOf(array, value, index);
    }

    /**
     * Gets all but the last element of `array`.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Array
     * @param {Array} array The array to query.
     * @returns {Array} Returns the slice of `array`.
     * @example
     *
     * _.initial([1, 2, 3]);
     * // => [1, 2]
     */
    function initial(array) {
      var length = array == null ? 0 : array.length;
      return length ? baseSlice(array, 0, -1) : [];
    }

    /**
     * Creates an array of unique values that are included in all given arrays
     * using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
     * for equality comparisons. The order and references of result values are
     * determined by the first array.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Array
     * @param {...Array} [arrays] The arrays to inspect.
     * @returns {Array} Returns the new array of intersecting values.
     * @example
     *
     * _.intersection([2, 1], [2, 3]);
     * // => [2]
     */
    var intersection = baseRest(function(arrays) {
      var mapped = arrayMap(arrays, castArrayLikeObject);
      return (mapped.length && mapped[0] === arrays[0])
        ? baseIntersection(mapped)
        : [];
    });

    /**
     * This method is like `_.intersection` except that it accepts `iteratee`
     * which is invoked for each element of each `arrays` to generate the criterion
     * by which they're compared. The order and references of result values are
     * determined by the first array. The iteratee is invoked with one argument:
     * (value).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {...Array} [arrays] The arrays to inspect.
     * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
     * @returns {Array} Returns the new array of intersecting values.
     * @example
     *
     * _.intersectionBy([2.1, 1.2], [2.3, 3.4], Math.floor);
     * // => [2.1]
     *
     * // The `_.property` iteratee shorthand.
     * _.intersectionBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x');
     * // => [{ 'x': 1 }]
     */
    var intersectionBy = baseRest(function(arrays) {
      var iteratee = last(arrays),
          mapped = arrayMap(arrays, castArrayLikeObject);

      if (iteratee === last(mapped)) {
        iteratee = undefined;
      } else {
        mapped.pop();
      }
      return (mapped.length && mapped[0] === arrays[0])
        ? baseIntersection(mapped, getIteratee(iteratee, 2))
        : [];
    });

    /**
     * This method is like `_.intersection` except that it accepts `comparator`
     * which is invoked to compare elements of `arrays`. The order and references
     * of result values are determined by the first array. The comparator is
     * invoked with two arguments: (arrVal, othVal).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {...Array} [arrays] The arrays to inspect.
     * @param {Function} [comparator] The comparator invoked per element.
     * @returns {Array} Returns the new array of intersecting values.
     * @example
     *
     * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }];
     * var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }];
     *
     * _.intersectionWith(objects, others, _.isEqual);
     * // => [{ 'x': 1, 'y': 2 }]
     */
    var intersectionWith = baseRest(function(arrays) {
      var comparator = last(arrays),
          mapped = arrayMap(arrays, castArrayLikeObject);

      comparator = typeof comparator == 'function' ? comparator : undefined;
      if (comparator) {
        mapped.pop();
      }
      return (mapped.length && mapped[0] === arrays[0])
        ? baseIntersection(mapped, undefined, comparator)
        : [];
    });

    /**
     * Converts all elements in `array` into a string separated by `separator`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {Array} array The array to convert.
     * @param {string} [separator=','] The element separator.
     * @returns {string} Returns the joined string.
     * @example
     *
     * _.join(['a', 'b', 'c'], '~');
     * // => 'a~b~c'
     */
    function join(array, separator) {
      return array == null ? '' : nativeJoin.call(array, separator);
    }

    /**
     * Gets the last element of `array`.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Array
     * @param {Array} array The array to query.
     * @returns {*} Returns the last element of `array`.
     * @example
     *
     * _.last([1, 2, 3]);
     * // => 3
     */
    function last(array) {
      var length = array == null ? 0 : array.length;
      return length ? array[length - 1] : undefined;
    }

    /**
     * This method is like `_.indexOf` except that it iterates over elements of
     * `array` from right to left.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Array
     * @param {Array} array The array to inspect.
     * @param {*} value The value to search for.
     * @param {number} [fromIndex=array.length-1] The index to search from.
     * @returns {number} Returns the index of the matched value, else `-1`.
     * @example
     *
     * _.lastIndexOf([1, 2, 1, 2], 2);
     * // => 3
     *
     * // Search from the `fromIndex`.
     * _.lastIndexOf([1, 2, 1, 2], 2, 2);
     * // => 1
     */
    function lastIndexOf(array, value, fromIndex) {
      var length = array == null ? 0 : array.length;
      if (!length) {
        return -1;
      }
      var index = length;
      if (fromIndex !== undefined) {
        index = toInteger(fromIndex);
        index = index < 0 ? nativeMax(length + index, 0) : nativeMin(index, length - 1);
      }
      return value === value
        ? strictLastIndexOf(array, value, index)
        : baseFindIndex(array, baseIsNaN, index, true);
    }

    /**
     * Gets the element at index `n` of `array`. If `n` is negative, the nth
     * element from the end is returned.
     *
     * @static
     * @memberOf _
     * @since 4.11.0
     * @category Array
     * @param {Array} array The array to query.
     * @param {number} [n=0] The index of the element to return.
     * @returns {*} Returns the nth element of `array`.
     * @example
     *
     * var array = ['a', 'b', 'c', 'd'];
     *
     * _.nth(array, 1);
     * // => 'b'
     *
     * _.nth(array, -2);
     * // => 'c';
     */
    function nth(array, n) {
      return (array && array.length) ? baseNth(array, toInteger(n)) : undefined;
    }

    /**
     * Removes all given values from `array` using
     * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
     * for equality comparisons.
     *
     * **Note:** Unlike `_.without`, this method mutates `array`. Use `_.remove`
     * to remove elements from an array by predicate.
     *
     * @static
     * @memberOf _
     * @since 2.0.0
     * @category Array
     * @param {Array} array The array to modify.
     * @param {...*} [values] The values to remove.
     * @returns {Array} Returns `array`.
     * @example
     *
     * var array = ['a', 'b', 'c', 'a', 'b', 'c'];
     *
     * _.pull(array, 'a', 'c');
     * console.log(array);
     * // => ['b', 'b']
     */
    var pull = baseRest(pullAll);

    /**
     * This method is like `_.pull` except that it accepts an array of values to remove.
     *
     * **Note:** Unlike `_.difference`, this method mutates `array`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {Array} array The array to modify.
     * @param {Array} values The values to remove.
     * @returns {Array} Returns `array`.
     * @example
     *
     * var array = ['a', 'b', 'c', 'a', 'b', 'c'];
     *
     * _.pullAll(array, ['a', 'c']);
     * console.log(array);
     * // => ['b', 'b']
     */
    function pullAll(array, values) {
      return (array && array.length && values && values.length)
        ? basePullAll(array, values)
        : array;
    }

    /**
     * This method is like `_.pullAll` except that it accepts `iteratee` which is
     * invoked for each element of `array` and `values` to generate the criterion
     * by which they're compared. The iteratee is invoked with one argument: (value).
     *
     * **Note:** Unlike `_.differenceBy`, this method mutates `array`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {Array} array The array to modify.
     * @param {Array} values The values to remove.
     * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
     * @returns {Array} Returns `array`.
     * @example
     *
     * var array = [{ 'x': 1 }, { 'x': 2 }, { 'x': 3 }, { 'x': 1 }];
     *
     * _.pullAllBy(array, [{ 'x': 1 }, { 'x': 3 }], 'x');
     * console.log(array);
     * // => [{ 'x': 2 }]
     */
    function pullAllBy(array, values, iteratee) {
      return (array && array.length && values && values.length)
        ? basePullAll(array, values, getIteratee(iteratee, 2))
        : array;
    }

    /**
     * This method is like `_.pullAll` except that it accepts `comparator` which
     * is invoked to compare elements of `array` to `values`. The comparator is
     * invoked with two arguments: (arrVal, othVal).
     *
     * **Note:** Unlike `_.differenceWith`, this method mutates `array`.
     *
     * @static
     * @memberOf _
     * @since 4.6.0
     * @category Array
     * @param {Array} array The array to modify.
     * @param {Array} values The values to remove.
     * @param {Function} [comparator] The comparator invoked per element.
     * @returns {Array} Returns `array`.
     * @example
     *
     * var array = [{ 'x': 1, 'y': 2 }, { 'x': 3, 'y': 4 }, { 'x': 5, 'y': 6 }];
     *
     * _.pullAllWith(array, [{ 'x': 3, 'y': 4 }], _.isEqual);
     * console.log(array);
     * // => [{ 'x': 1, 'y': 2 }, { 'x': 5, 'y': 6 }]
     */
    function pullAllWith(array, values, comparator) {
      return (array && array.length && values && values.length)
        ? basePullAll(array, values, undefined, comparator)
        : array;
    }

    /**
     * Removes elements from `array` corresponding to `indexes` and returns an
     * array of removed elements.
     *
     * **Note:** Unlike `_.at`, this method mutates `array`.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Array
     * @param {Array} array The array to modify.
     * @param {...(number|number[])} [indexes] The indexes of elements to remove.
     * @returns {Array} Returns the new array of removed elements.
     * @example
     *
     * var array = ['a', 'b', 'c', 'd'];
     * var pulled = _.pullAt(array, [1, 3]);
     *
     * console.log(array);
     * // => ['a', 'c']
     *
     * console.log(pulled);
     * // => ['b', 'd']
     */
    var pullAt = flatRest(function(array, indexes) {
      var length = array == null ? 0 : array.length,
          result = baseAt(array, indexes);

      basePullAt(array, arrayMap(indexes, function(index) {
        return isIndex(index, length) ? +index : index;
      }).sort(compareAscending));

      return result;
    });

    /**
     * Removes all elements from `array` that `predicate` returns truthy for
     * and returns an array of the removed elements. The predicate is invoked
     * with three arguments: (value, index, array).
     *
     * **Note:** Unlike `_.filter`, this method mutates `array`. Use `_.pull`
     * to pull elements from an array by value.
     *
     * @static
     * @memberOf _
     * @since 2.0.0
     * @category Array
     * @param {Array} array The array to modify.
     * @param {Function} [predicate=_.identity] The function invoked per iteration.
     * @returns {Array} Returns the new array of removed elements.
     * @example
     *
     * var array = [1, 2, 3, 4];
     * var evens = _.remove(array, function(n) {
     *   return n % 2 == 0;
     * });
     *
     * console.log(array);
     * // => [1, 3]
     *
     * console.log(evens);
     * // => [2, 4]
     */
    function remove(array, predicate) {
      var result = [];
      if (!(array && array.length)) {
        return result;
      }
      var index = -1,
          indexes = [],
          length = array.length;

      predicate = getIteratee(predicate, 3);
      while (++index < length) {
        var value = array[index];
        if (predicate(value, index, array)) {
          result.push(value);
          indexes.push(index);
        }
      }
      basePullAt(array, indexes);
      return result;
    }

    /**
     * Reverses `array` so that the first element becomes the last, the second
     * element becomes the second to last, and so on.
     *
     * **Note:** This method mutates `array` and is based on
     * [`Array#reverse`](https://mdn.io/Array/reverse).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {Array} array The array to modify.
     * @returns {Array} Returns `array`.
     * @example
     *
     * var array = [1, 2, 3];
     *
     * _.reverse(array);
     * // => [3, 2, 1]
     *
     * console.log(array);
     * // => [3, 2, 1]
     */
    function reverse(array) {
      return array == null ? array : nativeReverse.call(array);
    }

    /**
     * Creates a slice of `array` from `start` up to, but not including, `end`.
     *
     * **Note:** This method is used instead of
     * [`Array#slice`](https://mdn.io/Array/slice) to ensure dense arrays are
     * returned.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Array
     * @param {Array} array The array to slice.
     * @param {number} [start=0] The start position.
     * @param {number} [end=array.length] The end position.
     * @returns {Array} Returns the slice of `array`.
     */
    function slice(array, start, end) {
      var length = array == null ? 0 : array.length;
      if (!length) {
        return [];
      }
      if (end && typeof end != 'number' && isIterateeCall(array, start, end)) {
        start = 0;
        end = length;
      }
      else {
        start = start == null ? 0 : toInteger(start);
        end = end === undefined ? length : toInteger(end);
      }
      return baseSlice(array, start, end);
    }

    /**
     * Uses a binary search to determine the lowest index at which `value`
     * should be inserted into `array` in order to maintain its sort order.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Array
     * @param {Array} array The sorted array to inspect.
     * @param {*} value The value to evaluate.
     * @returns {number} Returns the index at which `value` should be inserted
     *  into `array`.
     * @example
     *
     * _.sortedIndex([30, 50], 40);
     * // => 1
     */
    function sortedIndex(array, value) {
      return baseSortedIndex(array, value);
    }

    /**
     * This method is like `_.sortedIndex` except that it accepts `iteratee`
     * which is invoked for `value` and each element of `array` to compute their
     * sort ranking. The iteratee is invoked with one argument: (value).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {Array} array The sorted array to inspect.
     * @param {*} value The value to evaluate.
     * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
     * @returns {number} Returns the index at which `value` should be inserted
     *  into `array`.
     * @example
     *
     * var objects = [{ 'x': 4 }, { 'x': 5 }];
     *
     * _.sortedIndexBy(objects, { 'x': 4 }, function(o) { return o.x; });
     * // => 0
     *
     * // The `_.property` iteratee shorthand.
     * _.sortedIndexBy(objects, { 'x': 4 }, 'x');
     * // => 0
     */
    function sortedIndexBy(array, value, iteratee) {
      return baseSortedIndexBy(array, value, getIteratee(iteratee, 2));
    }

    /**
     * This method is like `_.indexOf` except that it performs a binary
     * search on a sorted `array`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {Array} array The array to inspect.
     * @param {*} value The value to search for.
     * @returns {number} Returns the index of the matched value, else `-1`.
     * @example
     *
     * _.sortedIndexOf([4, 5, 5, 5, 6], 5);
     * // => 1
     */
    function sortedIndexOf(array, value) {
      var length = array == null ? 0 : array.length;
      if (length) {
        var index = baseSortedIndex(array, value);
        if (index < length && eq(array[index], value)) {
          return index;
        }
      }
      return -1;
    }

    /**
     * This method is like `_.sortedIndex` except that it returns the highest
     * index at which `value` should be inserted into `array` in order to
     * maintain its sort order.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Array
     * @param {Array} array The sorted array to inspect.
     * @param {*} value The value to evaluate.
     * @returns {number} Returns the index at which `value` should be inserted
     *  into `array`.
     * @example
     *
     * _.sortedLastIndex([4, 5, 5, 5, 6], 5);
     * // => 4
     */
    function sortedLastIndex(array, value) {
      return baseSortedIndex(array, value, true);
    }

    /**
     * This method is like `_.sortedLastIndex` except that it accepts `iteratee`
     * which is invoked for `value` and each element of `array` to compute their
     * sort ranking. The iteratee is invoked with one argument: (value).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {Array} array The sorted array to inspect.
     * @param {*} value The value to evaluate.
     * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
     * @returns {number} Returns the index at which `value` should be inserted
     *  into `array`.
     * @example
     *
     * var objects = [{ 'x': 4 }, { 'x': 5 }];
     *
     * _.sortedLastIndexBy(objects, { 'x': 4 }, function(o) { return o.x; });
     * // => 1
     *
     * // The `_.property` iteratee shorthand.
     * _.sortedLastIndexBy(objects, { 'x': 4 }, 'x');
     * // => 1
     */
    function sortedLastIndexBy(array, value, iteratee) {
      return baseSortedIndexBy(array, value, getIteratee(iteratee, 2), true);
    }

    /**
     * This method is like `_.lastIndexOf` except that it performs a binary
     * search on a sorted `array`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {Array} array The array to inspect.
     * @param {*} value The value to search for.
     * @returns {number} Returns the index of the matched value, else `-1`.
     * @example
     *
     * _.sortedLastIndexOf([4, 5, 5, 5, 6], 5);
     * // => 3
     */
    function sortedLastIndexOf(array, value) {
      var length = array == null ? 0 : array.length;
      if (length) {
        var index = baseSortedIndex(array, value, true) - 1;
        if (eq(array[index], value)) {
          return index;
        }
      }
      return -1;
    }

    /**
     * This method is like `_.uniq` except that it's designed and optimized
     * for sorted arrays.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {Array} array The array to inspect.
     * @returns {Array} Returns the new duplicate free array.
     * @example
     *
     * _.sortedUniq([1, 1, 2]);
     * // => [1, 2]
     */
    function sortedUniq(array) {
      return (array && array.length)
        ? baseSortedUniq(array)
        : [];
    }

    /**
     * This method is like `_.uniqBy` except that it's designed and optimized
     * for sorted arrays.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {Array} array The array to inspect.
     * @param {Function} [iteratee] The iteratee invoked per element.
     * @returns {Array} Returns the new duplicate free array.
     * @example
     *
     * _.sortedUniqBy([1.1, 1.2, 2.3, 2.4], Math.floor);
     * // => [1.1, 2.3]
     */
    function sortedUniqBy(array, iteratee) {
      return (array && array.length)
        ? baseSortedUniq(array, getIteratee(iteratee, 2))
        : [];
    }

    /**
     * Gets all but the first element of `array`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {Array} array The array to query.
     * @returns {Array} Returns the slice of `array`.
     * @example
     *
     * _.tail([1, 2, 3]);
     * // => [2, 3]
     */
    function tail(array) {
      var length = array == null ? 0 : array.length;
      return length ? baseSlice(array, 1, length) : [];
    }

    /**
     * Creates a slice of `array` with `n` elements taken from the beginning.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Array
     * @param {Array} array The array to query.
     * @param {number} [n=1] The number of elements to take.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
     * @returns {Array} Returns the slice of `array`.
     * @example
     *
     * _.take([1, 2, 3]);
     * // => [1]
     *
     * _.take([1, 2, 3], 2);
     * // => [1, 2]
     *
     * _.take([1, 2, 3], 5);
     * // => [1, 2, 3]
     *
     * _.take([1, 2, 3], 0);
     * // => []
     */
    function take(array, n, guard) {
      if (!(array && array.length)) {
        return [];
      }
      n = (guard || n === undefined) ? 1 : toInteger(n);
      return baseSlice(array, 0, n < 0 ? 0 : n);
    }

    /**
     * Creates a slice of `array` with `n` elements taken from the end.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Array
     * @param {Array} array The array to query.
     * @param {number} [n=1] The number of elements to take.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
     * @returns {Array} Returns the slice of `array`.
     * @example
     *
     * _.takeRight([1, 2, 3]);
     * // => [3]
     *
     * _.takeRight([1, 2, 3], 2);
     * // => [2, 3]
     *
     * _.takeRight([1, 2, 3], 5);
     * // => [1, 2, 3]
     *
     * _.takeRight([1, 2, 3], 0);
     * // => []
     */
    function takeRight(array, n, guard) {
      var length = array == null ? 0 : array.length;
      if (!length) {
        return [];
      }
      n = (guard || n === undefined) ? 1 : toInteger(n);
      n = length - n;
      return baseSlice(array, n < 0 ? 0 : n, length);
    }

    /**
     * Creates a slice of `array` with elements taken from the end. Elements are
     * taken until `predicate` returns falsey. The predicate is invoked with
     * three arguments: (value, index, array).
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Array
     * @param {Array} array The array to query.
     * @param {Function} [predicate=_.identity] The function invoked per iteration.
     * @returns {Array} Returns the slice of `array`.
     * @example
     *
     * var users = [
     *   { 'user': 'barney',  'active': true },
     *   { 'user': 'fred',    'active': false },
     *   { 'user': 'pebbles', 'active': false }
     * ];
     *
     * _.takeRightWhile(users, function(o) { return !o.active; });
     * // => objects for ['fred', 'pebbles']
     *
     * // The `_.matches` iteratee shorthand.
     * _.takeRightWhile(users, { 'user': 'pebbles', 'active': false });
     * // => objects for ['pebbles']
     *
     * // The `_.matchesProperty` iteratee shorthand.
     * _.takeRightWhile(users, ['active', false]);
     * // => objects for ['fred', 'pebbles']
     *
     * // The `_.property` iteratee shorthand.
     * _.takeRightWhile(users, 'active');
     * // => []
     */
    function takeRightWhile(array, predicate) {
      return (array && array.length)
        ? baseWhile(array, getIteratee(predicate, 3), false, true)
        : [];
    }

    /**
     * Creates a slice of `array` with elements taken from the beginning. Elements
     * are taken until `predicate` returns falsey. The predicate is invoked with
     * three arguments: (value, index, array).
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Array
     * @param {Array} array The array to query.
     * @param {Function} [predicate=_.identity] The function invoked per iteration.
     * @returns {Array} Returns the slice of `array`.
     * @example
     *
     * var users = [
     *   { 'user': 'barney',  'active': false },
     *   { 'user': 'fred',    'active': false },
     *   { 'user': 'pebbles', 'active': true }
     * ];
     *
     * _.takeWhile(users, function(o) { return !o.active; });
     * // => objects for ['barney', 'fred']
     *
     * // The `_.matches` iteratee shorthand.
     * _.takeWhile(users, { 'user': 'barney', 'active': false });
     * // => objects for ['barney']
     *
     * // The `_.matchesProperty` iteratee shorthand.
     * _.takeWhile(users, ['active', false]);
     * // => objects for ['barney', 'fred']
     *
     * // The `_.property` iteratee shorthand.
     * _.takeWhile(users, 'active');
     * // => []
     */
    function takeWhile(array, predicate) {
      return (array && array.length)
        ? baseWhile(array, getIteratee(predicate, 3))
        : [];
    }

    /**
     * Creates an array of unique values, in order, from all given arrays using
     * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
     * for equality comparisons.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Array
     * @param {...Array} [arrays] The arrays to inspect.
     * @returns {Array} Returns the new array of combined values.
     * @example
     *
     * _.union([2], [1, 2]);
     * // => [2, 1]
     */
    var union = baseRest(function(arrays) {
      return baseUniq(baseFlatten(arrays, 1, isArrayLikeObject, true));
    });

    /**
     * This method is like `_.union` except that it accepts `iteratee` which is
     * invoked for each element of each `arrays` to generate the criterion by
     * which uniqueness is computed. Result values are chosen from the first
     * array in which the value occurs. The iteratee is invoked with one argument:
     * (value).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {...Array} [arrays] The arrays to inspect.
     * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
     * @returns {Array} Returns the new array of combined values.
     * @example
     *
     * _.unionBy([2.1], [1.2, 2.3], Math.floor);
     * // => [2.1, 1.2]
     *
     * // The `_.property` iteratee shorthand.
     * _.unionBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x');
     * // => [{ 'x': 1 }, { 'x': 2 }]
     */
    var unionBy = baseRest(function(arrays) {
      var iteratee = last(arrays);
      if (isArrayLikeObject(iteratee)) {
        iteratee = undefined;
      }
      return baseUniq(baseFlatten(arrays, 1, isArrayLikeObject, true), getIteratee(iteratee, 2));
    });

    /**
     * This method is like `_.union` except that it accepts `comparator` which
     * is invoked to compare elements of `arrays`. Result values are chosen from
     * the first array in which the value occurs. The comparator is invoked
     * with two arguments: (arrVal, othVal).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {...Array} [arrays] The arrays to inspect.
     * @param {Function} [comparator] The comparator invoked per element.
     * @returns {Array} Returns the new array of combined values.
     * @example
     *
     * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }];
     * var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }];
     *
     * _.unionWith(objects, others, _.isEqual);
     * // => [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }, { 'x': 1, 'y': 1 }]
     */
    var unionWith = baseRest(function(arrays) {
      var comparator = last(arrays);
      comparator = typeof comparator == 'function' ? comparator : undefined;
      return baseUniq(baseFlatten(arrays, 1, isArrayLikeObject, true), undefined, comparator);
    });

    /**
     * Creates a duplicate-free version of an array, using
     * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
     * for equality comparisons, in which only the first occurrence of each element
     * is kept. The order of result values is determined by the order they occur
     * in the array.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Array
     * @param {Array} array The array to inspect.
     * @returns {Array} Returns the new duplicate free array.
     * @example
     *
     * _.uniq([2, 1, 2]);
     * // => [2, 1]
     */
    function uniq(array) {
      return (array && array.length) ? baseUniq(array) : [];
    }

    /**
     * This method is like `_.uniq` except that it accepts `iteratee` which is
     * invoked for each element in `array` to generate the criterion by which
     * uniqueness is computed. The order of result values is determined by the
     * order they occur in the array. The iteratee is invoked with one argument:
     * (value).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {Array} array The array to inspect.
     * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
     * @returns {Array} Returns the new duplicate free array.
     * @example
     *
     * _.uniqBy([2.1, 1.2, 2.3], Math.floor);
     * // => [2.1, 1.2]
     *
     * // The `_.property` iteratee shorthand.
     * _.uniqBy([{ 'x': 1 }, { 'x': 2 }, { 'x': 1 }], 'x');
     * // => [{ 'x': 1 }, { 'x': 2 }]
     */
    function uniqBy(array, iteratee) {
      return (array && array.length) ? baseUniq(array, getIteratee(iteratee, 2)) : [];
    }

    /**
     * This method is like `_.uniq` except that it accepts `comparator` which
     * is invoked to compare elements of `array`. The order of result values is
     * determined by the order they occur in the array.The comparator is invoked
     * with two arguments: (arrVal, othVal).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {Array} array The array to inspect.
     * @param {Function} [comparator] The comparator invoked per element.
     * @returns {Array} Returns the new duplicate free array.
     * @example
     *
     * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }, { 'x': 1, 'y': 2 }];
     *
     * _.uniqWith(objects, _.isEqual);
     * // => [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }]
     */
    function uniqWith(array, comparator) {
      comparator = typeof comparator == 'function' ? comparator : undefined;
      return (array && array.length) ? baseUniq(array, undefined, comparator) : [];
    }

    /**
     * This method is like `_.zip` except that it accepts an array of grouped
     * elements and creates an array regrouping the elements to their pre-zip
     * configuration.
     *
     * @static
     * @memberOf _
     * @since 1.2.0
     * @category Array
     * @param {Array} array The array of grouped elements to process.
     * @returns {Array} Returns the new array of regrouped elements.
     * @example
     *
     * var zipped = _.zip(['a', 'b'], [1, 2], [true, false]);
     * // => [['a', 1, true], ['b', 2, false]]
     *
     * _.unzip(zipped);
     * // => [['a', 'b'], [1, 2], [true, false]]
     */
    function unzip(array) {
      if (!(array && array.length)) {
        return [];
      }
      var length = 0;
      array = arrayFilter(array, function(group) {
        if (isArrayLikeObject(group)) {
          length = nativeMax(group.length, length);
          return true;
        }
      });
      return baseTimes(length, function(index) {
        return arrayMap(array, baseProperty(index));
      });
    }

    /**
     * This method is like `_.unzip` except that it accepts `iteratee` to specify
     * how regrouped values should be combined. The iteratee is invoked with the
     * elements of each group: (...group).
     *
     * @static
     * @memberOf _
     * @since 3.8.0
     * @category Array
     * @param {Array} array The array of grouped elements to process.
     * @param {Function} [iteratee=_.identity] The function to combine
     *  regrouped values.
     * @returns {Array} Returns the new array of regrouped elements.
     * @example
     *
     * var zipped = _.zip([1, 2], [10, 20], [100, 200]);
     * // => [[1, 10, 100], [2, 20, 200]]
     *
     * _.unzipWith(zipped, _.add);
     * // => [3, 30, 300]
     */
    function unzipWith(array, iteratee) {
      if (!(array && array.length)) {
        return [];
      }
      var result = unzip(array);
      if (iteratee == null) {
        return result;
      }
      return arrayMap(result, function(group) {
        return apply(iteratee, undefined, group);
      });
    }

    /**
     * Creates an array excluding all given values using
     * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
     * for equality comparisons.
     *
     * **Note:** Unlike `_.pull`, this method returns a new array.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Array
     * @param {Array} array The array to inspect.
     * @param {...*} [values] The values to exclude.
     * @returns {Array} Returns the new array of filtered values.
     * @see _.difference, _.xor
     * @example
     *
     * _.without([2, 1, 2, 3], 1, 2);
     * // => [3]
     */
    var without = baseRest(function(array, values) {
      return isArrayLikeObject(array)
        ? baseDifference(array, values)
        : [];
    });

    /**
     * Creates an array of unique values that is the
     * [symmetric difference](https://en.wikipedia.org/wiki/Symmetric_difference)
     * of the given arrays. The order of result values is determined by the order
     * they occur in the arrays.
     *
     * @static
     * @memberOf _
     * @since 2.4.0
     * @category Array
     * @param {...Array} [arrays] The arrays to inspect.
     * @returns {Array} Returns the new array of filtered values.
     * @see _.difference, _.without
     * @example
     *
     * _.xor([2, 1], [2, 3]);
     * // => [1, 3]
     */
    var xor = baseRest(function(arrays) {
      return baseXor(arrayFilter(arrays, isArrayLikeObject));
    });

    /**
     * This method is like `_.xor` except that it accepts `iteratee` which is
     * invoked for each element of each `arrays` to generate the criterion by
     * which by which they're compared. The order of result values is determined
     * by the order they occur in the arrays. The iteratee is invoked with one
     * argument: (value).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {...Array} [arrays] The arrays to inspect.
     * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
     * @returns {Array} Returns the new array of filtered values.
     * @example
     *
     * _.xorBy([2.1, 1.2], [2.3, 3.4], Math.floor);
     * // => [1.2, 3.4]
     *
     * // The `_.property` iteratee shorthand.
     * _.xorBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x');
     * // => [{ 'x': 2 }]
     */
    var xorBy = baseRest(function(arrays) {
      var iteratee = last(arrays);
      if (isArrayLikeObject(iteratee)) {
        iteratee = undefined;
      }
      return baseXor(arrayFilter(arrays, isArrayLikeObject), getIteratee(iteratee, 2));
    });

    /**
     * This method is like `_.xor` except that it accepts `comparator` which is
     * invoked to compare elements of `arrays`. The order of result values is
     * determined by the order they occur in the arrays. The comparator is invoked
     * with two arguments: (arrVal, othVal).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Array
     * @param {...Array} [arrays] The arrays to inspect.
     * @param {Function} [comparator] The comparator invoked per element.
     * @returns {Array} Returns the new array of filtered values.
     * @example
     *
     * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }];
     * var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }];
     *
     * _.xorWith(objects, others, _.isEqual);
     * // => [{ 'x': 2, 'y': 1 }, { 'x': 1, 'y': 1 }]
     */
    var xorWith = baseRest(function(arrays) {
      var comparator = last(arrays);
      comparator = typeof comparator == 'function' ? comparator : undefined;
      return baseXor(arrayFilter(arrays, isArrayLikeObject), undefined, comparator);
    });

    /**
     * Creates an array of grouped elements, the first of which contains the
     * first elements of the given arrays, the second of which contains the
     * second elements of the given arrays, and so on.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Array
     * @param {...Array} [arrays] The arrays to process.
     * @returns {Array} Returns the new array of grouped elements.
     * @example
     *
     * _.zip(['a', 'b'], [1, 2], [true, false]);
     * // => [['a', 1, true], ['b', 2, false]]
     */
    var zip = baseRest(unzip);

    /**
     * This method is like `_.fromPairs` except that it accepts two arrays,
     * one of property identifiers and one of corresponding values.
     *
     * @static
     * @memberOf _
     * @since 0.4.0
     * @category Array
     * @param {Array} [props=[]] The property identifiers.
     * @param {Array} [values=[]] The property values.
     * @returns {Object} Returns the new object.
     * @example
     *
     * _.zipObject(['a', 'b'], [1, 2]);
     * // => { 'a': 1, 'b': 2 }
     */
    function zipObject(props, values) {
      return baseZipObject(props || [], values || [], assignValue);
    }

    /**
     * This method is like `_.zipObject` except that it supports property paths.
     *
     * @static
     * @memberOf _
     * @since 4.1.0
     * @category Array
     * @param {Array} [props=[]] The property identifiers.
     * @param {Array} [values=[]] The property values.
     * @returns {Object} Returns the new object.
     * @example
     *
     * _.zipObjectDeep(['a.b[0].c', 'a.b[1].d'], [1, 2]);
     * // => { 'a': { 'b': [{ 'c': 1 }, { 'd': 2 }] } }
     */
    function zipObjectDeep(props, values) {
      return baseZipObject(props || [], values || [], baseSet);
    }

    /**
     * This method is like `_.zip` except that it accepts `iteratee` to specify
     * how grouped values should be combined. The iteratee is invoked with the
     * elements of each group: (...group).
     *
     * @static
     * @memberOf _
     * @since 3.8.0
     * @category Array
     * @param {...Array} [arrays] The arrays to process.
     * @param {Function} [iteratee=_.identity] The function to combine
     *  grouped values.
     * @returns {Array} Returns the new array of grouped elements.
     * @example
     *
     * _.zipWith([1, 2], [10, 20], [100, 200], function(a, b, c) {
     *   return a + b + c;
     * });
     * // => [111, 222]
     */
    var zipWith = baseRest(function(arrays) {
      var length = arrays.length,
          iteratee = length > 1 ? arrays[length - 1] : undefined;

      iteratee = typeof iteratee == 'function' ? (arrays.pop(), iteratee) : undefined;
      return unzipWith(arrays, iteratee);
    });

    /*------------------------------------------------------------------------*/

    /**
     * Creates a `lodash` wrapper instance that wraps `value` with explicit method
     * chain sequences enabled. The result of such sequences must be unwrapped
     * with `_#value`.
     *
     * @static
     * @memberOf _
     * @since 1.3.0
     * @category Seq
     * @param {*} value The value to wrap.
     * @returns {Object} Returns the new `lodash` wrapper instance.
     * @example
     *
     * var users = [
     *   { 'user': 'barney',  'age': 36 },
     *   { 'user': 'fred',    'age': 40 },
     *   { 'user': 'pebbles', 'age': 1 }
     * ];
     *
     * var youngest = _
     *   .chain(users)
     *   .sortBy('age')
     *   .map(function(o) {
     *     return o.user + ' is ' + o.age;
     *   })
     *   .head()
     *   .value();
     * // => 'pebbles is 1'
     */
    function chain(value) {
      var result = lodash(value);
      result.__chain__ = true;
      return result;
    }

    /**
     * This method invokes `interceptor` and returns `value`. The interceptor
     * is invoked with one argument; (value). The purpose of this method is to
     * "tap into" a method chain sequence in order to modify intermediate results.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Seq
     * @param {*} value The value to provide to `interceptor`.
     * @param {Function} interceptor The function to invoke.
     * @returns {*} Returns `value`.
     * @example
     *
     * _([1, 2, 3])
     *  .tap(function(array) {
     *    // Mutate input array.
     *    array.pop();
     *  })
     *  .reverse()
     *  .value();
     * // => [2, 1]
     */
    function tap(value, interceptor) {
      interceptor(value);
      return value;
    }

    /**
     * This method is like `_.tap` except that it returns the result of `interceptor`.
     * The purpose of this method is to "pass thru" values replacing intermediate
     * results in a method chain sequence.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Seq
     * @param {*} value The value to provide to `interceptor`.
     * @param {Function} interceptor The function to invoke.
     * @returns {*} Returns the result of `interceptor`.
     * @example
     *
     * _('  abc  ')
     *  .chain()
     *  .trim()
     *  .thru(function(value) {
     *    return [value];
     *  })
     *  .value();
     * // => ['abc']
     */
    function thru(value, interceptor) {
      return interceptor(value);
    }

    /**
     * This method is the wrapper version of `_.at`.
     *
     * @name at
     * @memberOf _
     * @since 1.0.0
     * @category Seq
     * @param {...(string|string[])} [paths] The property paths to pick.
     * @returns {Object} Returns the new `lodash` wrapper instance.
     * @example
     *
     * var object = { 'a': [{ 'b': { 'c': 3 } }, 4] };
     *
     * _(object).at(['a[0].b.c', 'a[1]']).value();
     * // => [3, 4]
     */
    var wrapperAt = flatRest(function(paths) {
      var length = paths.length,
          start = length ? paths[0] : 0,
          value = this.__wrapped__,
          interceptor = function(object) { return baseAt(object, paths); };

      if (length > 1 || this.__actions__.length ||
          !(value instanceof LazyWrapper) || !isIndex(start)) {
        return this.thru(interceptor);
      }
      value = value.slice(start, +start + (length ? 1 : 0));
      value.__actions__.push({
        'func': thru,
        'args': [interceptor],
        'thisArg': undefined
      });
      return new LodashWrapper(value, this.__chain__).thru(function(array) {
        if (length && !array.length) {
          array.push(undefined);
        }
        return array;
      });
    });

    /**
     * Creates a `lodash` wrapper instance with explicit method chain sequences enabled.
     *
     * @name chain
     * @memberOf _
     * @since 0.1.0
     * @category Seq
     * @returns {Object} Returns the new `lodash` wrapper instance.
     * @example
     *
     * var users = [
     *   { 'user': 'barney', 'age': 36 },
     *   { 'user': 'fred',   'age': 40 }
     * ];
     *
     * // A sequence without explicit chaining.
     * _(users).head();
     * // => { 'user': 'barney', 'age': 36 }
     *
     * // A sequence with explicit chaining.
     * _(users)
     *   .chain()
     *   .head()
     *   .pick('user')
     *   .value();
     * // => { 'user': 'barney' }
     */
    function wrapperChain() {
      return chain(this);
    }

    /**
     * Executes the chain sequence and returns the wrapped result.
     *
     * @name commit
     * @memberOf _
     * @since 3.2.0
     * @category Seq
     * @returns {Object} Returns the new `lodash` wrapper instance.
     * @example
     *
     * var array = [1, 2];
     * var wrapped = _(array).push(3);
     *
     * console.log(array);
     * // => [1, 2]
     *
     * wrapped = wrapped.commit();
     * console.log(array);
     * // => [1, 2, 3]
     *
     * wrapped.last();
     * // => 3
     *
     * console.log(array);
     * // => [1, 2, 3]
     */
    function wrapperCommit() {
      return new LodashWrapper(this.value(), this.__chain__);
    }

    /**
     * Gets the next value on a wrapped object following the
     * [iterator protocol](https://mdn.io/iteration_protocols#iterator).
     *
     * @name next
     * @memberOf _
     * @since 4.0.0
     * @category Seq
     * @returns {Object} Returns the next iterator value.
     * @example
     *
     * var wrapped = _([1, 2]);
     *
     * wrapped.next();
     * // => { 'done': false, 'value': 1 }
     *
     * wrapped.next();
     * // => { 'done': false, 'value': 2 }
     *
     * wrapped.next();
     * // => { 'done': true, 'value': undefined }
     */
    function wrapperNext() {
      if (this.__values__ === undefined) {
        this.__values__ = toArray(this.value());
      }
      var done = this.__index__ >= this.__values__.length,
          value = done ? undefined : this.__values__[this.__index__++];

      return { 'done': done, 'value': value };
    }

    /**
     * Enables the wrapper to be iterable.
     *
     * @name Symbol.iterator
     * @memberOf _
     * @since 4.0.0
     * @category Seq
     * @returns {Object} Returns the wrapper object.
     * @example
     *
     * var wrapped = _([1, 2]);
     *
     * wrapped[Symbol.iterator]() === wrapped;
     * // => true
     *
     * Array.from(wrapped);
     * // => [1, 2]
     */
    function wrapperToIterator() {
      return this;
    }

    /**
     * Creates a clone of the chain sequence planting `value` as the wrapped value.
     *
     * @name plant
     * @memberOf _
     * @since 3.2.0
     * @category Seq
     * @param {*} value The value to plant.
     * @returns {Object} Returns the new `lodash` wrapper instance.
     * @example
     *
     * function square(n) {
     *   return n * n;
     * }
     *
     * var wrapped = _([1, 2]).map(square);
     * var other = wrapped.plant([3, 4]);
     *
     * other.value();
     * // => [9, 16]
     *
     * wrapped.value();
     * // => [1, 4]
     */
    function wrapperPlant(value) {
      var result,
          parent = this;

      while (parent instanceof baseLodash) {
        var clone = wrapperClone(parent);
        clone.__index__ = 0;
        clone.__values__ = undefined;
        if (result) {
          previous.__wrapped__ = clone;
        } else {
          result = clone;
        }
        var previous = clone;
        parent = parent.__wrapped__;
      }
      previous.__wrapped__ = value;
      return result;
    }

    /**
     * This method is the wrapper version of `_.reverse`.
     *
     * **Note:** This method mutates the wrapped array.
     *
     * @name reverse
     * @memberOf _
     * @since 0.1.0
     * @category Seq
     * @returns {Object} Returns the new `lodash` wrapper instance.
     * @example
     *
     * var array = [1, 2, 3];
     *
     * _(array).reverse().value()
     * // => [3, 2, 1]
     *
     * console.log(array);
     * // => [3, 2, 1]
     */
    function wrapperReverse() {
      var value = this.__wrapped__;
      if (value instanceof LazyWrapper) {
        var wrapped = value;
        if (this.__actions__.length) {
          wrapped = new LazyWrapper(this);
        }
        wrapped = wrapped.reverse();
        wrapped.__actions__.push({
          'func': thru,
          'args': [reverse],
          'thisArg': undefined
        });
        return new LodashWrapper(wrapped, this.__chain__);
      }
      return this.thru(reverse);
    }

    /**
     * Executes the chain sequence to resolve the unwrapped value.
     *
     * @name value
     * @memberOf _
     * @since 0.1.0
     * @alias toJSON, valueOf
     * @category Seq
     * @returns {*} Returns the resolved unwrapped value.
     * @example
     *
     * _([1, 2, 3]).value();
     * // => [1, 2, 3]
     */
    function wrapperValue() {
      return baseWrapperValue(this.__wrapped__, this.__actions__);
    }

    /*------------------------------------------------------------------------*/

    /**
     * Creates an object composed of keys generated from the results of running
     * each element of `collection` thru `iteratee`. The corresponding value of
     * each key is the number of times the key was returned by `iteratee`. The
     * iteratee is invoked with one argument: (value).
     *
     * @static
     * @memberOf _
     * @since 0.5.0
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} [iteratee=_.identity] The iteratee to transform keys.
     * @returns {Object} Returns the composed aggregate object.
     * @example
     *
     * _.countBy([6.1, 4.2, 6.3], Math.floor);
     * // => { '4': 1, '6': 2 }
     *
     * // The `_.property` iteratee shorthand.
     * _.countBy(['one', 'two', 'three'], 'length');
     * // => { '3': 2, '5': 1 }
     */
    var countBy = createAggregator(function(result, value, key) {
      if (hasOwnProperty.call(result, key)) {
        ++result[key];
      } else {
        baseAssignValue(result, key, 1);
      }
    });

    /**
     * Checks if `predicate` returns truthy for **all** elements of `collection`.
     * Iteration is stopped once `predicate` returns falsey. The predicate is
     * invoked with three arguments: (value, index|key, collection).
     *
     * **Note:** This method returns `true` for
     * [empty collections](https://en.wikipedia.org/wiki/Empty_set) because
     * [everything is true](https://en.wikipedia.org/wiki/Vacuous_truth) of
     * elements of empty collections.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} [predicate=_.identity] The function invoked per iteration.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
     * @returns {boolean} Returns `true` if all elements pass the predicate check,
     *  else `false`.
     * @example
     *
     * _.every([true, 1, null, 'yes'], Boolean);
     * // => false
     *
     * var users = [
     *   { 'user': 'barney', 'age': 36, 'active': false },
     *   { 'user': 'fred',   'age': 40, 'active': false }
     * ];
     *
     * // The `_.matches` iteratee shorthand.
     * _.every(users, { 'user': 'barney', 'active': false });
     * // => false
     *
     * // The `_.matchesProperty` iteratee shorthand.
     * _.every(users, ['active', false]);
     * // => true
     *
     * // The `_.property` iteratee shorthand.
     * _.every(users, 'active');
     * // => false
     */
    function every(collection, predicate, guard) {
      var func = isArray(collection) ? arrayEvery : baseEvery;
      if (guard && isIterateeCall(collection, predicate, guard)) {
        predicate = undefined;
      }
      return func(collection, getIteratee(predicate, 3));
    }

    /**
     * Iterates over elements of `collection`, returning an array of all elements
     * `predicate` returns truthy for. The predicate is invoked with three
     * arguments: (value, index|key, collection).
     *
     * **Note:** Unlike `_.remove`, this method returns a new array.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} [predicate=_.identity] The function invoked per iteration.
     * @returns {Array} Returns the new filtered array.
     * @see _.reject
     * @example
     *
     * var users = [
     *   { 'user': 'barney', 'age': 36, 'active': true },
     *   { 'user': 'fred',   'age': 40, 'active': false }
     * ];
     *
     * _.filter(users, function(o) { return !o.active; });
     * // => objects for ['fred']
     *
     * // The `_.matches` iteratee shorthand.
     * _.filter(users, { 'age': 36, 'active': true });
     * // => objects for ['barney']
     *
     * // The `_.matchesProperty` iteratee shorthand.
     * _.filter(users, ['active', false]);
     * // => objects for ['fred']
     *
     * // The `_.property` iteratee shorthand.
     * _.filter(users, 'active');
     * // => objects for ['barney']
     */
    function filter(collection, predicate) {
      var func = isArray(collection) ? arrayFilter : baseFilter;
      return func(collection, getIteratee(predicate, 3));
    }

    /**
     * Iterates over elements of `collection`, returning the first element
     * `predicate` returns truthy for. The predicate is invoked with three
     * arguments: (value, index|key, collection).
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Collection
     * @param {Array|Object} collection The collection to inspect.
     * @param {Function} [predicate=_.identity] The function invoked per iteration.
     * @param {number} [fromIndex=0] The index to search from.
     * @returns {*} Returns the matched element, else `undefined`.
     * @example
     *
     * var users = [
     *   { 'user': 'barney',  'age': 36, 'active': true },
     *   { 'user': 'fred',    'age': 40, 'active': false },
     *   { 'user': 'pebbles', 'age': 1,  'active': true }
     * ];
     *
     * _.find(users, function(o) { return o.age < 40; });
     * // => object for 'barney'
     *
     * // The `_.matches` iteratee shorthand.
     * _.find(users, { 'age': 1, 'active': true });
     * // => object for 'pebbles'
     *
     * // The `_.matchesProperty` iteratee shorthand.
     * _.find(users, ['active', false]);
     * // => object for 'fred'
     *
     * // The `_.property` iteratee shorthand.
     * _.find(users, 'active');
     * // => object for 'barney'
     */
    var find = createFind(findIndex);

    /**
     * This method is like `_.find` except that it iterates over elements of
     * `collection` from right to left.
     *
     * @static
     * @memberOf _
     * @since 2.0.0
     * @category Collection
     * @param {Array|Object} collection The collection to inspect.
     * @param {Function} [predicate=_.identity] The function invoked per iteration.
     * @param {number} [fromIndex=collection.length-1] The index to search from.
     * @returns {*} Returns the matched element, else `undefined`.
     * @example
     *
     * _.findLast([1, 2, 3, 4], function(n) {
     *   return n % 2 == 1;
     * });
     * // => 3
     */
    var findLast = createFind(findLastIndex);

    /**
     * Creates a flattened array of values by running each element in `collection`
     * thru `iteratee` and flattening the mapped results. The iteratee is invoked
     * with three arguments: (value, index|key, collection).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} [iteratee=_.identity] The function invoked per iteration.
     * @returns {Array} Returns the new flattened array.
     * @example
     *
     * function duplicate(n) {
     *   return [n, n];
     * }
     *
     * _.flatMap([1, 2], duplicate);
     * // => [1, 1, 2, 2]
     */
    function flatMap(collection, iteratee) {
      return baseFlatten(map(collection, iteratee), 1);
    }

    /**
     * This method is like `_.flatMap` except that it recursively flattens the
     * mapped results.
     *
     * @static
     * @memberOf _
     * @since 4.7.0
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} [iteratee=_.identity] The function invoked per iteration.
     * @returns {Array} Returns the new flattened array.
     * @example
     *
     * function duplicate(n) {
     *   return [[[n, n]]];
     * }
     *
     * _.flatMapDeep([1, 2], duplicate);
     * // => [1, 1, 2, 2]
     */
    function flatMapDeep(collection, iteratee) {
      return baseFlatten(map(collection, iteratee), INFINITY);
    }

    /**
     * This method is like `_.flatMap` except that it recursively flattens the
     * mapped results up to `depth` times.
     *
     * @static
     * @memberOf _
     * @since 4.7.0
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} [iteratee=_.identity] The function invoked per iteration.
     * @param {number} [depth=1] The maximum recursion depth.
     * @returns {Array} Returns the new flattened array.
     * @example
     *
     * function duplicate(n) {
     *   return [[[n, n]]];
     * }
     *
     * _.flatMapDepth([1, 2], duplicate, 2);
     * // => [[1, 1], [2, 2]]
     */
    function flatMapDepth(collection, iteratee, depth) {
      depth = depth === undefined ? 1 : toInteger(depth);
      return baseFlatten(map(collection, iteratee), depth);
    }

    /**
     * Iterates over elements of `collection` and invokes `iteratee` for each element.
     * The iteratee is invoked with three arguments: (value, index|key, collection).
     * Iteratee functions may exit iteration early by explicitly returning `false`.
     *
     * **Note:** As with other "Collections" methods, objects with a "length"
     * property are iterated like arrays. To avoid this behavior use `_.forIn`
     * or `_.forOwn` for object iteration.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @alias each
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} [iteratee=_.identity] The function invoked per iteration.
     * @returns {Array|Object} Returns `collection`.
     * @see _.forEachRight
     * @example
     *
     * _.forEach([1, 2], function(value) {
     *   console.log(value);
     * });
     * // => Logs `1` then `2`.
     *
     * _.forEach({ 'a': 1, 'b': 2 }, function(value, key) {
     *   console.log(key);
     * });
     * // => Logs 'a' then 'b' (iteration order is not guaranteed).
     */
    function forEach(collection, iteratee) {
      var func = isArray(collection) ? arrayEach : baseEach;
      return func(collection, getIteratee(iteratee, 3));
    }

    /**
     * This method is like `_.forEach` except that it iterates over elements of
     * `collection` from right to left.
     *
     * @static
     * @memberOf _
     * @since 2.0.0
     * @alias eachRight
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} [iteratee=_.identity] The function invoked per iteration.
     * @returns {Array|Object} Returns `collection`.
     * @see _.forEach
     * @example
     *
     * _.forEachRight([1, 2], function(value) {
     *   console.log(value);
     * });
     * // => Logs `2` then `1`.
     */
    function forEachRight(collection, iteratee) {
      var func = isArray(collection) ? arrayEachRight : baseEachRight;
      return func(collection, getIteratee(iteratee, 3));
    }

    /**
     * Creates an object composed of keys generated from the results of running
     * each element of `collection` thru `iteratee`. The order of grouped values
     * is determined by the order they occur in `collection`. The corresponding
     * value of each key is an array of elements responsible for generating the
     * key. The iteratee is invoked with one argument: (value).
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} [iteratee=_.identity] The iteratee to transform keys.
     * @returns {Object} Returns the composed aggregate object.
     * @example
     *
     * _.groupBy([6.1, 4.2, 6.3], Math.floor);
     * // => { '4': [4.2], '6': [6.1, 6.3] }
     *
     * // The `_.property` iteratee shorthand.
     * _.groupBy(['one', 'two', 'three'], 'length');
     * // => { '3': ['one', 'two'], '5': ['three'] }
     */
    var groupBy = createAggregator(function(result, value, key) {
      if (hasOwnProperty.call(result, key)) {
        result[key].push(value);
      } else {
        baseAssignValue(result, key, [value]);
      }
    });

    /**
     * Checks if `value` is in `collection`. If `collection` is a string, it's
     * checked for a substring of `value`, otherwise
     * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
     * is used for equality comparisons. If `fromIndex` is negative, it's used as
     * the offset from the end of `collection`.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Collection
     * @param {Array|Object|string} collection The collection to inspect.
     * @param {*} value The value to search for.
     * @param {number} [fromIndex=0] The index to search from.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.reduce`.
     * @returns {boolean} Returns `true` if `value` is found, else `false`.
     * @example
     *
     * _.includes([1, 2, 3], 1);
     * // => true
     *
     * _.includes([1, 2, 3], 1, 2);
     * // => false
     *
     * _.includes({ 'a': 1, 'b': 2 }, 1);
     * // => true
     *
     * _.includes('abcd', 'bc');
     * // => true
     */
    function includes(collection, value, fromIndex, guard) {
      collection = isArrayLike(collection) ? collection : values(collection);
      fromIndex = (fromIndex && !guard) ? toInteger(fromIndex) : 0;

      var length = collection.length;
      if (fromIndex < 0) {
        fromIndex = nativeMax(length + fromIndex, 0);
      }
      return isString(collection)
        ? (fromIndex <= length && collection.indexOf(value, fromIndex) > -1)
        : (!!length && baseIndexOf(collection, value, fromIndex) > -1);
    }

    /**
     * Invokes the method at `path` of each element in `collection`, returning
     * an array of the results of each invoked method. Any additional arguments
     * are provided to each invoked method. If `path` is a function, it's invoked
     * for, and `this` bound to, each element in `collection`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Array|Function|string} path The path of the method to invoke or
     *  the function invoked per iteration.
     * @param {...*} [args] The arguments to invoke each method with.
     * @returns {Array} Returns the array of results.
     * @example
     *
     * _.invokeMap([[5, 1, 7], [3, 2, 1]], 'sort');
     * // => [[1, 5, 7], [1, 2, 3]]
     *
     * _.invokeMap([123, 456], String.prototype.split, '');
     * // => [['1', '2', '3'], ['4', '5', '6']]
     */
    var invokeMap = baseRest(function(collection, path, args) {
      var index = -1,
          isFunc = typeof path == 'function',
          result = isArrayLike(collection) ? Array(collection.length) : [];

      baseEach(collection, function(value) {
        result[++index] = isFunc ? apply(path, value, args) : baseInvoke(value, path, args);
      });
      return result;
    });

    /**
     * Creates an object composed of keys generated from the results of running
     * each element of `collection` thru `iteratee`. The corresponding value of
     * each key is the last element responsible for generating the key. The
     * iteratee is invoked with one argument: (value).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} [iteratee=_.identity] The iteratee to transform keys.
     * @returns {Object} Returns the composed aggregate object.
     * @example
     *
     * var array = [
     *   { 'dir': 'left', 'code': 97 },
     *   { 'dir': 'right', 'code': 100 }
     * ];
     *
     * _.keyBy(array, function(o) {
     *   return String.fromCharCode(o.code);
     * });
     * // => { 'a': { 'dir': 'left', 'code': 97 }, 'd': { 'dir': 'right', 'code': 100 } }
     *
     * _.keyBy(array, 'dir');
     * // => { 'left': { 'dir': 'left', 'code': 97 }, 'right': { 'dir': 'right', 'code': 100 } }
     */
    var keyBy = createAggregator(function(result, value, key) {
      baseAssignValue(result, key, value);
    });

    /**
     * Creates an array of values by running each element in `collection` thru
     * `iteratee`. The iteratee is invoked with three arguments:
     * (value, index|key, collection).
     *
     * Many lodash methods are guarded to work as iteratees for methods like
     * `_.every`, `_.filter`, `_.map`, `_.mapValues`, `_.reject`, and `_.some`.
     *
     * The guarded methods are:
     * `ary`, `chunk`, `curry`, `curryRight`, `drop`, `dropRight`, `every`,
     * `fill`, `invert`, `parseInt`, `random`, `range`, `rangeRight`, `repeat`,
     * `sampleSize`, `slice`, `some`, `sortBy`, `split`, `take`, `takeRight`,
     * `template`, `trim`, `trimEnd`, `trimStart`, and `words`
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} [iteratee=_.identity] The function invoked per iteration.
     * @returns {Array} Returns the new mapped array.
     * @example
     *
     * function square(n) {
     *   return n * n;
     * }
     *
     * _.map([4, 8], square);
     * // => [16, 64]
     *
     * _.map({ 'a': 4, 'b': 8 }, square);
     * // => [16, 64] (iteration order is not guaranteed)
     *
     * var users = [
     *   { 'user': 'barney' },
     *   { 'user': 'fred' }
     * ];
     *
     * // The `_.property` iteratee shorthand.
     * _.map(users, 'user');
     * // => ['barney', 'fred']
     */
    function map(collection, iteratee) {
      var func = isArray(collection) ? arrayMap : baseMap;
      return func(collection, getIteratee(iteratee, 3));
    }

    /**
     * This method is like `_.sortBy` except that it allows specifying the sort
     * orders of the iteratees to sort by. If `orders` is unspecified, all values
     * are sorted in ascending order. Otherwise, specify an order of "desc" for
     * descending or "asc" for ascending sort order of corresponding values.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Array[]|Function[]|Object[]|string[]} [iteratees=[_.identity]]
     *  The iteratees to sort by.
     * @param {string[]} [orders] The sort orders of `iteratees`.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.reduce`.
     * @returns {Array} Returns the new sorted array.
     * @example
     *
     * var users = [
     *   { 'user': 'fred',   'age': 48 },
     *   { 'user': 'barney', 'age': 34 },
     *   { 'user': 'fred',   'age': 40 },
     *   { 'user': 'barney', 'age': 36 }
     * ];
     *
     * // Sort by `user` in ascending order and by `age` in descending order.
     * _.orderBy(users, ['user', 'age'], ['asc', 'desc']);
     * // => objects for [['barney', 36], ['barney', 34], ['fred', 48], ['fred', 40]]
     */
    function orderBy(collection, iteratees, orders, guard) {
      if (collection == null) {
        return [];
      }
      if (!isArray(iteratees)) {
        iteratees = iteratees == null ? [] : [iteratees];
      }
      orders = guard ? undefined : orders;
      if (!isArray(orders)) {
        orders = orders == null ? [] : [orders];
      }
      return baseOrderBy(collection, iteratees, orders);
    }

    /**
     * Creates an array of elements split into two groups, the first of which
     * contains elements `predicate` returns truthy for, the second of which
     * contains elements `predicate` returns falsey for. The predicate is
     * invoked with one argument: (value).
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} [predicate=_.identity] The function invoked per iteration.
     * @returns {Array} Returns the array of grouped elements.
     * @example
     *
     * var users = [
     *   { 'user': 'barney',  'age': 36, 'active': false },
     *   { 'user': 'fred',    'age': 40, 'active': true },
     *   { 'user': 'pebbles', 'age': 1,  'active': false }
     * ];
     *
     * _.partition(users, function(o) { return o.active; });
     * // => objects for [['fred'], ['barney', 'pebbles']]
     *
     * // The `_.matches` iteratee shorthand.
     * _.partition(users, { 'age': 1, 'active': false });
     * // => objects for [['pebbles'], ['barney', 'fred']]
     *
     * // The `_.matchesProperty` iteratee shorthand.
     * _.partition(users, ['active', false]);
     * // => objects for [['barney', 'pebbles'], ['fred']]
     *
     * // The `_.property` iteratee shorthand.
     * _.partition(users, 'active');
     * // => objects for [['fred'], ['barney', 'pebbles']]
     */
    var partition = createAggregator(function(result, value, key) {
      result[key ? 0 : 1].push(value);
    }, function() { return [[], []]; });

    /**
     * Reduces `collection` to a value which is the accumulated result of running
     * each element in `collection` thru `iteratee`, where each successive
     * invocation is supplied the return value of the previous. If `accumulator`
     * is not given, the first element of `collection` is used as the initial
     * value. The iteratee is invoked with four arguments:
     * (accumulator, value, index|key, collection).
     *
     * Many lodash methods are guarded to work as iteratees for methods like
     * `_.reduce`, `_.reduceRight`, and `_.transform`.
     *
     * The guarded methods are:
     * `assign`, `defaults`, `defaultsDeep`, `includes`, `merge`, `orderBy`,
     * and `sortBy`
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} [iteratee=_.identity] The function invoked per iteration.
     * @param {*} [accumulator] The initial value.
     * @returns {*} Returns the accumulated value.
     * @see _.reduceRight
     * @example
     *
     * _.reduce([1, 2], function(sum, n) {
     *   return sum + n;
     * }, 0);
     * // => 3
     *
     * _.reduce({ 'a': 1, 'b': 2, 'c': 1 }, function(result, value, key) {
     *   (result[value] || (result[value] = [])).push(key);
     *   return result;
     * }, {});
     * // => { '1': ['a', 'c'], '2': ['b'] } (iteration order is not guaranteed)
     */
    function reduce(collection, iteratee, accumulator) {
      var func = isArray(collection) ? arrayReduce : baseReduce,
          initAccum = arguments.length < 3;

      return func(collection, getIteratee(iteratee, 4), accumulator, initAccum, baseEach);
    }

    /**
     * This method is like `_.reduce` except that it iterates over elements of
     * `collection` from right to left.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} [iteratee=_.identity] The function invoked per iteration.
     * @param {*} [accumulator] The initial value.
     * @returns {*} Returns the accumulated value.
     * @see _.reduce
     * @example
     *
     * var array = [[0, 1], [2, 3], [4, 5]];
     *
     * _.reduceRight(array, function(flattened, other) {
     *   return flattened.concat(other);
     * }, []);
     * // => [4, 5, 2, 3, 0, 1]
     */
    function reduceRight(collection, iteratee, accumulator) {
      var func = isArray(collection) ? arrayReduceRight : baseReduce,
          initAccum = arguments.length < 3;

      return func(collection, getIteratee(iteratee, 4), accumulator, initAccum, baseEachRight);
    }

    /**
     * The opposite of `_.filter`; this method returns the elements of `collection`
     * that `predicate` does **not** return truthy for.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} [predicate=_.identity] The function invoked per iteration.
     * @returns {Array} Returns the new filtered array.
     * @see _.filter
     * @example
     *
     * var users = [
     *   { 'user': 'barney', 'age': 36, 'active': false },
     *   { 'user': 'fred',   'age': 40, 'active': true }
     * ];
     *
     * _.reject(users, function(o) { return !o.active; });
     * // => objects for ['fred']
     *
     * // The `_.matches` iteratee shorthand.
     * _.reject(users, { 'age': 40, 'active': true });
     * // => objects for ['barney']
     *
     * // The `_.matchesProperty` iteratee shorthand.
     * _.reject(users, ['active', false]);
     * // => objects for ['fred']
     *
     * // The `_.property` iteratee shorthand.
     * _.reject(users, 'active');
     * // => objects for ['barney']
     */
    function reject(collection, predicate) {
      var func = isArray(collection) ? arrayFilter : baseFilter;
      return func(collection, negate(getIteratee(predicate, 3)));
    }

    /**
     * Gets a random element from `collection`.
     *
     * @static
     * @memberOf _
     * @since 2.0.0
     * @category Collection
     * @param {Array|Object} collection The collection to sample.
     * @returns {*} Returns the random element.
     * @example
     *
     * _.sample([1, 2, 3, 4]);
     * // => 2
     */
    function sample(collection) {
      var func = isArray(collection) ? arraySample : baseSample;
      return func(collection);
    }

    /**
     * Gets `n` random elements at unique keys from `collection` up to the
     * size of `collection`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Collection
     * @param {Array|Object} collection The collection to sample.
     * @param {number} [n=1] The number of elements to sample.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
     * @returns {Array} Returns the random elements.
     * @example
     *
     * _.sampleSize([1, 2, 3], 2);
     * // => [3, 1]
     *
     * _.sampleSize([1, 2, 3], 4);
     * // => [2, 3, 1]
     */
    function sampleSize(collection, n, guard) {
      if ((guard ? isIterateeCall(collection, n, guard) : n === undefined)) {
        n = 1;
      } else {
        n = toInteger(n);
      }
      var func = isArray(collection) ? arraySampleSize : baseSampleSize;
      return func(collection, n);
    }

    /**
     * Creates an array of shuffled values, using a version of the
     * [Fisher-Yates shuffle](https://en.wikipedia.org/wiki/Fisher-Yates_shuffle).
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Collection
     * @param {Array|Object} collection The collection to shuffle.
     * @returns {Array} Returns the new shuffled array.
     * @example
     *
     * _.shuffle([1, 2, 3, 4]);
     * // => [4, 1, 3, 2]
     */
    function shuffle(collection) {
      var func = isArray(collection) ? arrayShuffle : baseShuffle;
      return func(collection);
    }

    /**
     * Gets the size of `collection` by returning its length for array-like
     * values or the number of own enumerable string keyed properties for objects.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Collection
     * @param {Array|Object|string} collection The collection to inspect.
     * @returns {number} Returns the collection size.
     * @example
     *
     * _.size([1, 2, 3]);
     * // => 3
     *
     * _.size({ 'a': 1, 'b': 2 });
     * // => 2
     *
     * _.size('pebbles');
     * // => 7
     */
    function size(collection) {
      if (collection == null) {
        return 0;
      }
      if (isArrayLike(collection)) {
        return isString(collection) ? stringSize(collection) : collection.length;
      }
      var tag = getTag(collection);
      if (tag == mapTag || tag == setTag) {
        return collection.size;
      }
      return baseKeys(collection).length;
    }

    /**
     * Checks if `predicate` returns truthy for **any** element of `collection`.
     * Iteration is stopped once `predicate` returns truthy. The predicate is
     * invoked with three arguments: (value, index|key, collection).
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {Function} [predicate=_.identity] The function invoked per iteration.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
     * @returns {boolean} Returns `true` if any element passes the predicate check,
     *  else `false`.
     * @example
     *
     * _.some([null, 0, 'yes', false], Boolean);
     * // => true
     *
     * var users = [
     *   { 'user': 'barney', 'active': true },
     *   { 'user': 'fred',   'active': false }
     * ];
     *
     * // The `_.matches` iteratee shorthand.
     * _.some(users, { 'user': 'barney', 'active': false });
     * // => false
     *
     * // The `_.matchesProperty` iteratee shorthand.
     * _.some(users, ['active', false]);
     * // => true
     *
     * // The `_.property` iteratee shorthand.
     * _.some(users, 'active');
     * // => true
     */
    function some(collection, predicate, guard) {
      var func = isArray(collection) ? arraySome : baseSome;
      if (guard && isIterateeCall(collection, predicate, guard)) {
        predicate = undefined;
      }
      return func(collection, getIteratee(predicate, 3));
    }

    /**
     * Creates an array of elements, sorted in ascending order by the results of
     * running each element in a collection thru each iteratee. This method
     * performs a stable sort, that is, it preserves the original sort order of
     * equal elements. The iteratees are invoked with one argument: (value).
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Collection
     * @param {Array|Object} collection The collection to iterate over.
     * @param {...(Function|Function[])} [iteratees=[_.identity]]
     *  The iteratees to sort by.
     * @returns {Array} Returns the new sorted array.
     * @example
     *
     * var users = [
     *   { 'user': 'fred',   'age': 48 },
     *   { 'user': 'barney', 'age': 36 },
     *   { 'user': 'fred',   'age': 40 },
     *   { 'user': 'barney', 'age': 34 }
     * ];
     *
     * _.sortBy(users, [function(o) { return o.user; }]);
     * // => objects for [['barney', 36], ['barney', 34], ['fred', 48], ['fred', 40]]
     *
     * _.sortBy(users, ['user', 'age']);
     * // => objects for [['barney', 34], ['barney', 36], ['fred', 40], ['fred', 48]]
     */
    var sortBy = baseRest(function(collection, iteratees) {
      if (collection == null) {
        return [];
      }
      var length = iteratees.length;
      if (length > 1 && isIterateeCall(collection, iteratees[0], iteratees[1])) {
        iteratees = [];
      } else if (length > 2 && isIterateeCall(iteratees[0], iteratees[1], iteratees[2])) {
        iteratees = [iteratees[0]];
      }
      return baseOrderBy(collection, baseFlatten(iteratees, 1), []);
    });

    /*------------------------------------------------------------------------*/

    /**
     * Gets the timestamp of the number of milliseconds that have elapsed since
     * the Unix epoch (1 January 1970 00:00:00 UTC).
     *
     * @static
     * @memberOf _
     * @since 2.4.0
     * @category Date
     * @returns {number} Returns the timestamp.
     * @example
     *
     * _.defer(function(stamp) {
     *   console.log(_.now() - stamp);
     * }, _.now());
     * // => Logs the number of milliseconds it took for the deferred invocation.
     */
    var now = ctxNow || function() {
      return root.Date.now();
    };

    /*------------------------------------------------------------------------*/

    /**
     * The opposite of `_.before`; this method creates a function that invokes
     * `func` once it's called `n` or more times.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Function
     * @param {number} n The number of calls before `func` is invoked.
     * @param {Function} func The function to restrict.
     * @returns {Function} Returns the new restricted function.
     * @example
     *
     * var saves = ['profile', 'settings'];
     *
     * var done = _.after(saves.length, function() {
     *   console.log('done saving!');
     * });
     *
     * _.forEach(saves, function(type) {
     *   asyncSave({ 'type': type, 'complete': done });
     * });
     * // => Logs 'done saving!' after the two async saves have completed.
     */
    function after(n, func) {
      if (typeof func != 'function') {
        throw new TypeError(FUNC_ERROR_TEXT);
      }
      n = toInteger(n);
      return function() {
        if (--n < 1) {
          return func.apply(this, arguments);
        }
      };
    }

    /**
     * Creates a function that invokes `func`, with up to `n` arguments,
     * ignoring any additional arguments.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Function
     * @param {Function} func The function to cap arguments for.
     * @param {number} [n=func.length] The arity cap.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
     * @returns {Function} Returns the new capped function.
     * @example
     *
     * _.map(['6', '8', '10'], _.ary(parseInt, 1));
     * // => [6, 8, 10]
     */
    function ary(func, n, guard) {
      n = guard ? undefined : n;
      n = (func && n == null) ? func.length : n;
      return createWrap(func, WRAP_ARY_FLAG, undefined, undefined, undefined, undefined, n);
    }

    /**
     * Creates a function that invokes `func`, with the `this` binding and arguments
     * of the created function, while it's called less than `n` times. Subsequent
     * calls to the created function return the result of the last `func` invocation.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Function
     * @param {number} n The number of calls at which `func` is no longer invoked.
     * @param {Function} func The function to restrict.
     * @returns {Function} Returns the new restricted function.
     * @example
     *
     * jQuery(element).on('click', _.before(5, addContactToList));
     * // => Allows adding up to 4 contacts to the list.
     */
    function before(n, func) {
      var result;
      if (typeof func != 'function') {
        throw new TypeError(FUNC_ERROR_TEXT);
      }
      n = toInteger(n);
      return function() {
        if (--n > 0) {
          result = func.apply(this, arguments);
        }
        if (n <= 1) {
          func = undefined;
        }
        return result;
      };
    }

    /**
     * Creates a function that invokes `func` with the `this` binding of `thisArg`
     * and `partials` prepended to the arguments it receives.
     *
     * The `_.bind.placeholder` value, which defaults to `_` in monolithic builds,
     * may be used as a placeholder for partially applied arguments.
     *
     * **Note:** Unlike native `Function#bind`, this method doesn't set the "length"
     * property of bound functions.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Function
     * @param {Function} func The function to bind.
     * @param {*} thisArg The `this` binding of `func`.
     * @param {...*} [partials] The arguments to be partially applied.
     * @returns {Function} Returns the new bound function.
     * @example
     *
     * function greet(greeting, punctuation) {
     *   return greeting + ' ' + this.user + punctuation;
     * }
     *
     * var object = { 'user': 'fred' };
     *
     * var bound = _.bind(greet, object, 'hi');
     * bound('!');
     * // => 'hi fred!'
     *
     * // Bound with placeholders.
     * var bound = _.bind(greet, object, _, '!');
     * bound('hi');
     * // => 'hi fred!'
     */
    var bind = baseRest(function(func, thisArg, partials) {
      var bitmask = WRAP_BIND_FLAG;
      if (partials.length) {
        var holders = replaceHolders(partials, getHolder(bind));
        bitmask |= WRAP_PARTIAL_FLAG;
      }
      return createWrap(func, bitmask, thisArg, partials, holders);
    });

    /**
     * Creates a function that invokes the method at `object[key]` with `partials`
     * prepended to the arguments it receives.
     *
     * This method differs from `_.bind` by allowing bound functions to reference
     * methods that may be redefined or don't yet exist. See
     * [Peter Michaux's article](http://peter.michaux.ca/articles/lazy-function-definition-pattern)
     * for more details.
     *
     * The `_.bindKey.placeholder` value, which defaults to `_` in monolithic
     * builds, may be used as a placeholder for partially applied arguments.
     *
     * @static
     * @memberOf _
     * @since 0.10.0
     * @category Function
     * @param {Object} object The object to invoke the method on.
     * @param {string} key The key of the method.
     * @param {...*} [partials] The arguments to be partially applied.
     * @returns {Function} Returns the new bound function.
     * @example
     *
     * var object = {
     *   'user': 'fred',
     *   'greet': function(greeting, punctuation) {
     *     return greeting + ' ' + this.user + punctuation;
     *   }
     * };
     *
     * var bound = _.bindKey(object, 'greet', 'hi');
     * bound('!');
     * // => 'hi fred!'
     *
     * object.greet = function(greeting, punctuation) {
     *   return greeting + 'ya ' + this.user + punctuation;
     * };
     *
     * bound('!');
     * // => 'hiya fred!'
     *
     * // Bound with placeholders.
     * var bound = _.bindKey(object, 'greet', _, '!');
     * bound('hi');
     * // => 'hiya fred!'
     */
    var bindKey = baseRest(function(object, key, partials) {
      var bitmask = WRAP_BIND_FLAG | WRAP_BIND_KEY_FLAG;
      if (partials.length) {
        var holders = replaceHolders(partials, getHolder(bindKey));
        bitmask |= WRAP_PARTIAL_FLAG;
      }
      return createWrap(key, bitmask, object, partials, holders);
    });

    /**
     * Creates a function that accepts arguments of `func` and either invokes
     * `func` returning its result, if at least `arity` number of arguments have
     * been provided, or returns a function that accepts the remaining `func`
     * arguments, and so on. The arity of `func` may be specified if `func.length`
     * is not sufficient.
     *
     * The `_.curry.placeholder` value, which defaults to `_` in monolithic builds,
     * may be used as a placeholder for provided arguments.
     *
     * **Note:** This method doesn't set the "length" property of curried functions.
     *
     * @static
     * @memberOf _
     * @since 2.0.0
     * @category Function
     * @param {Function} func The function to curry.
     * @param {number} [arity=func.length] The arity of `func`.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
     * @returns {Function} Returns the new curried function.
     * @example
     *
     * var abc = function(a, b, c) {
     *   return [a, b, c];
     * };
     *
     * var curried = _.curry(abc);
     *
     * curried(1)(2)(3);
     * // => [1, 2, 3]
     *
     * curried(1, 2)(3);
     * // => [1, 2, 3]
     *
     * curried(1, 2, 3);
     * // => [1, 2, 3]
     *
     * // Curried with placeholders.
     * curried(1)(_, 3)(2);
     * // => [1, 2, 3]
     */
    function curry(func, arity, guard) {
      arity = guard ? undefined : arity;
      var result = createWrap(func, WRAP_CURRY_FLAG, undefined, undefined, undefined, undefined, undefined, arity);
      result.placeholder = curry.placeholder;
      return result;
    }

    /**
     * This method is like `_.curry` except that arguments are applied to `func`
     * in the manner of `_.partialRight` instead of `_.partial`.
     *
     * The `_.curryRight.placeholder` value, which defaults to `_` in monolithic
     * builds, may be used as a placeholder for provided arguments.
     *
     * **Note:** This method doesn't set the "length" property of curried functions.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Function
     * @param {Function} func The function to curry.
     * @param {number} [arity=func.length] The arity of `func`.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
     * @returns {Function} Returns the new curried function.
     * @example
     *
     * var abc = function(a, b, c) {
     *   return [a, b, c];
     * };
     *
     * var curried = _.curryRight(abc);
     *
     * curried(3)(2)(1);
     * // => [1, 2, 3]
     *
     * curried(2, 3)(1);
     * // => [1, 2, 3]
     *
     * curried(1, 2, 3);
     * // => [1, 2, 3]
     *
     * // Curried with placeholders.
     * curried(3)(1, _)(2);
     * // => [1, 2, 3]
     */
    function curryRight(func, arity, guard) {
      arity = guard ? undefined : arity;
      var result = createWrap(func, WRAP_CURRY_RIGHT_FLAG, undefined, undefined, undefined, undefined, undefined, arity);
      result.placeholder = curryRight.placeholder;
      return result;
    }

    /**
     * Creates a debounced function that delays invoking `func` until after `wait`
     * milliseconds have elapsed since the last time the debounced function was
     * invoked. The debounced function comes with a `cancel` method to cancel
     * delayed `func` invocations and a `flush` method to immediately invoke them.
     * Provide `options` to indicate whether `func` should be invoked on the
     * leading and/or trailing edge of the `wait` timeout. The `func` is invoked
     * with the last arguments provided to the debounced function. Subsequent
     * calls to the debounced function return the result of the last `func`
     * invocation.
     *
     * **Note:** If `leading` and `trailing` options are `true`, `func` is
     * invoked on the trailing edge of the timeout only if the debounced function
     * is invoked more than once during the `wait` timeout.
     *
     * If `wait` is `0` and `leading` is `false`, `func` invocation is deferred
     * until to the next tick, similar to `setTimeout` with a timeout of `0`.
     *
     * See [David Corbacho's article](https://css-tricks.com/debouncing-throttling-explained-examples/)
     * for details over the differences between `_.debounce` and `_.throttle`.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Function
     * @param {Function} func The function to debounce.
     * @param {number} [wait=0] The number of milliseconds to delay.
     * @param {Object} [options={}] The options object.
     * @param {boolean} [options.leading=false]
     *  Specify invoking on the leading edge of the timeout.
     * @param {number} [options.maxWait]
     *  The maximum time `func` is allowed to be delayed before it's invoked.
     * @param {boolean} [options.trailing=true]
     *  Specify invoking on the trailing edge of the timeout.
     * @returns {Function} Returns the new debounced function.
     * @example
     *
     * // Avoid costly calculations while the window size is in flux.
     * jQuery(window).on('resize', _.debounce(calculateLayout, 150));
     *
     * // Invoke `sendMail` when clicked, debouncing subsequent calls.
     * jQuery(element).on('click', _.debounce(sendMail, 300, {
     *   'leading': true,
     *   'trailing': false
     * }));
     *
     * // Ensure `batchLog` is invoked once after 1 second of debounced calls.
     * var debounced = _.debounce(batchLog, 250, { 'maxWait': 1000 });
     * var source = new EventSource('/stream');
     * jQuery(source).on('message', debounced);
     *
     * // Cancel the trailing debounced invocation.
     * jQuery(window).on('popstate', debounced.cancel);
     */
    function debounce(func, wait, options) {
      var lastArgs,
          lastThis,
          maxWait,
          result,
          timerId,
          lastCallTime,
          lastInvokeTime = 0,
          leading = false,
          maxing = false,
          trailing = true;

      if (typeof func != 'function') {
        throw new TypeError(FUNC_ERROR_TEXT);
      }
      wait = toNumber(wait) || 0;
      if (isObject(options)) {
        leading = !!options.leading;
        maxing = 'maxWait' in options;
        maxWait = maxing ? nativeMax(toNumber(options.maxWait) || 0, wait) : maxWait;
        trailing = 'trailing' in options ? !!options.trailing : trailing;
      }

      function invokeFunc(time) {
        var args = lastArgs,
            thisArg = lastThis;

        lastArgs = lastThis = undefined;
        lastInvokeTime = time;
        result = func.apply(thisArg, args);
        return result;
      }

      function leadingEdge(time) {
        // Reset any `maxWait` timer.
        lastInvokeTime = time;
        // Start the timer for the trailing edge.
        timerId = setTimeout(timerExpired, wait);
        // Invoke the leading edge.
        return leading ? invokeFunc(time) : result;
      }

      function remainingWait(time) {
        var timeSinceLastCall = time - lastCallTime,
            timeSinceLastInvoke = time - lastInvokeTime,
            result = wait - timeSinceLastCall;

        return maxing ? nativeMin(result, maxWait - timeSinceLastInvoke) : result;
      }

      function shouldInvoke(time) {
        var timeSinceLastCall = time - lastCallTime,
            timeSinceLastInvoke = time - lastInvokeTime;

        // Either this is the first call, activity has stopped and we're at the
        // trailing edge, the system time has gone backwards and we're treating
        // it as the trailing edge, or we've hit the `maxWait` limit.
        return (lastCallTime === undefined || (timeSinceLastCall >= wait) ||
          (timeSinceLastCall < 0) || (maxing && timeSinceLastInvoke >= maxWait));
      }

      function timerExpired() {
        var time = now();
        if (shouldInvoke(time)) {
          return trailingEdge(time);
        }
        // Restart the timer.
        timerId = setTimeout(timerExpired, remainingWait(time));
      }

      function trailingEdge(time) {
        timerId = undefined;

        // Only invoke if we have `lastArgs` which means `func` has been
        // debounced at least once.
        if (trailing && lastArgs) {
          return invokeFunc(time);
        }
        lastArgs = lastThis = undefined;
        return result;
      }

      function cancel() {
        if (timerId !== undefined) {
          clearTimeout(timerId);
        }
        lastInvokeTime = 0;
        lastArgs = lastCallTime = lastThis = timerId = undefined;
      }

      function flush() {
        return timerId === undefined ? result : trailingEdge(now());
      }

      function debounced() {
        var time = now(),
            isInvoking = shouldInvoke(time);

        lastArgs = arguments;
        lastThis = this;
        lastCallTime = time;

        if (isInvoking) {
          if (timerId === undefined) {
            return leadingEdge(lastCallTime);
          }
          if (maxing) {
            // Handle invocations in a tight loop.
            timerId = setTimeout(timerExpired, wait);
            return invokeFunc(lastCallTime);
          }
        }
        if (timerId === undefined) {
          timerId = setTimeout(timerExpired, wait);
        }
        return result;
      }
      debounced.cancel = cancel;
      debounced.flush = flush;
      return debounced;
    }

    /**
     * Defers invoking the `func` until the current call stack has cleared. Any
     * additional arguments are provided to `func` when it's invoked.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Function
     * @param {Function} func The function to defer.
     * @param {...*} [args] The arguments to invoke `func` with.
     * @returns {number} Returns the timer id.
     * @example
     *
     * _.defer(function(text) {
     *   console.log(text);
     * }, 'deferred');
     * // => Logs 'deferred' after one millisecond.
     */
    var defer = baseRest(function(func, args) {
      return baseDelay(func, 1, args);
    });

    /**
     * Invokes `func` after `wait` milliseconds. Any additional arguments are
     * provided to `func` when it's invoked.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Function
     * @param {Function} func The function to delay.
     * @param {number} wait The number of milliseconds to delay invocation.
     * @param {...*} [args] The arguments to invoke `func` with.
     * @returns {number} Returns the timer id.
     * @example
     *
     * _.delay(function(text) {
     *   console.log(text);
     * }, 1000, 'later');
     * // => Logs 'later' after one second.
     */
    var delay = baseRest(function(func, wait, args) {
      return baseDelay(func, toNumber(wait) || 0, args);
    });

    /**
     * Creates a function that invokes `func` with arguments reversed.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Function
     * @param {Function} func The function to flip arguments for.
     * @returns {Function} Returns the new flipped function.
     * @example
     *
     * var flipped = _.flip(function() {
     *   return _.toArray(arguments);
     * });
     *
     * flipped('a', 'b', 'c', 'd');
     * // => ['d', 'c', 'b', 'a']
     */
    function flip(func) {
      return createWrap(func, WRAP_FLIP_FLAG);
    }

    /**
     * Creates a function that memoizes the result of `func`. If `resolver` is
     * provided, it determines the cache key for storing the result based on the
     * arguments provided to the memoized function. By default, the first argument
     * provided to the memoized function is used as the map cache key. The `func`
     * is invoked with the `this` binding of the memoized function.
     *
     * **Note:** The cache is exposed as the `cache` property on the memoized
     * function. Its creation may be customized by replacing the `_.memoize.Cache`
     * constructor with one whose instances implement the
     * [`Map`](http://ecma-international.org/ecma-262/7.0/#sec-properties-of-the-map-prototype-object)
     * method interface of `clear`, `delete`, `get`, `has`, and `set`.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Function
     * @param {Function} func The function to have its output memoized.
     * @param {Function} [resolver] The function to resolve the cache key.
     * @returns {Function} Returns the new memoized function.
     * @example
     *
     * var object = { 'a': 1, 'b': 2 };
     * var other = { 'c': 3, 'd': 4 };
     *
     * var values = _.memoize(_.values);
     * values(object);
     * // => [1, 2]
     *
     * values(other);
     * // => [3, 4]
     *
     * object.a = 2;
     * values(object);
     * // => [1, 2]
     *
     * // Modify the result cache.
     * values.cache.set(object, ['a', 'b']);
     * values(object);
     * // => ['a', 'b']
     *
     * // Replace `_.memoize.Cache`.
     * _.memoize.Cache = WeakMap;
     */
    function memoize(func, resolver) {
      if (typeof func != 'function' || (resolver != null && typeof resolver != 'function')) {
        throw new TypeError(FUNC_ERROR_TEXT);
      }
      var memoized = function() {
        var args = arguments,
            key = resolver ? resolver.apply(this, args) : args[0],
            cache = memoized.cache;

        if (cache.has(key)) {
          return cache.get(key);
        }
        var result = func.apply(this, args);
        memoized.cache = cache.set(key, result) || cache;
        return result;
      };
      memoized.cache = new (memoize.Cache || MapCache);
      return memoized;
    }

    // Expose `MapCache`.
    memoize.Cache = MapCache;

    /**
     * Creates a function that negates the result of the predicate `func`. The
     * `func` predicate is invoked with the `this` binding and arguments of the
     * created function.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Function
     * @param {Function} predicate The predicate to negate.
     * @returns {Function} Returns the new negated function.
     * @example
     *
     * function isEven(n) {
     *   return n % 2 == 0;
     * }
     *
     * _.filter([1, 2, 3, 4, 5, 6], _.negate(isEven));
     * // => [1, 3, 5]
     */
    function negate(predicate) {
      if (typeof predicate != 'function') {
        throw new TypeError(FUNC_ERROR_TEXT);
      }
      return function() {
        var args = arguments;
        switch (args.length) {
          case 0: return !predicate.call(this);
          case 1: return !predicate.call(this, args[0]);
          case 2: return !predicate.call(this, args[0], args[1]);
          case 3: return !predicate.call(this, args[0], args[1], args[2]);
        }
        return !predicate.apply(this, args);
      };
    }

    /**
     * Creates a function that is restricted to invoking `func` once. Repeat calls
     * to the function return the value of the first invocation. The `func` is
     * invoked with the `this` binding and arguments of the created function.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Function
     * @param {Function} func The function to restrict.
     * @returns {Function} Returns the new restricted function.
     * @example
     *
     * var initialize = _.once(createApplication);
     * initialize();
     * initialize();
     * // => `createApplication` is invoked once
     */
    function once(func) {
      return before(2, func);
    }

    /**
     * Creates a function that invokes `func` with its arguments transformed.
     *
     * @static
     * @since 4.0.0
     * @memberOf _
     * @category Function
     * @param {Function} func The function to wrap.
     * @param {...(Function|Function[])} [transforms=[_.identity]]
     *  The argument transforms.
     * @returns {Function} Returns the new function.
     * @example
     *
     * function doubled(n) {
     *   return n * 2;
     * }
     *
     * function square(n) {
     *   return n * n;
     * }
     *
     * var func = _.overArgs(function(x, y) {
     *   return [x, y];
     * }, [square, doubled]);
     *
     * func(9, 3);
     * // => [81, 6]
     *
     * func(10, 5);
     * // => [100, 10]
     */
    var overArgs = castRest(function(func, transforms) {
      transforms = (transforms.length == 1 && isArray(transforms[0]))
        ? arrayMap(transforms[0], baseUnary(getIteratee()))
        : arrayMap(baseFlatten(transforms, 1), baseUnary(getIteratee()));

      var funcsLength = transforms.length;
      return baseRest(function(args) {
        var index = -1,
            length = nativeMin(args.length, funcsLength);

        while (++index < length) {
          args[index] = transforms[index].call(this, args[index]);
        }
        return apply(func, this, args);
      });
    });

    /**
     * Creates a function that invokes `func` with `partials` prepended to the
     * arguments it receives. This method is like `_.bind` except it does **not**
     * alter the `this` binding.
     *
     * The `_.partial.placeholder` value, which defaults to `_` in monolithic
     * builds, may be used as a placeholder for partially applied arguments.
     *
     * **Note:** This method doesn't set the "length" property of partially
     * applied functions.
     *
     * @static
     * @memberOf _
     * @since 0.2.0
     * @category Function
     * @param {Function} func The function to partially apply arguments to.
     * @param {...*} [partials] The arguments to be partially applied.
     * @returns {Function} Returns the new partially applied function.
     * @example
     *
     * function greet(greeting, name) {
     *   return greeting + ' ' + name;
     * }
     *
     * var sayHelloTo = _.partial(greet, 'hello');
     * sayHelloTo('fred');
     * // => 'hello fred'
     *
     * // Partially applied with placeholders.
     * var greetFred = _.partial(greet, _, 'fred');
     * greetFred('hi');
     * // => 'hi fred'
     */
    var partial = baseRest(function(func, partials) {
      var holders = replaceHolders(partials, getHolder(partial));
      return createWrap(func, WRAP_PARTIAL_FLAG, undefined, partials, holders);
    });

    /**
     * This method is like `_.partial` except that partially applied arguments
     * are appended to the arguments it receives.
     *
     * The `_.partialRight.placeholder` value, which defaults to `_` in monolithic
     * builds, may be used as a placeholder for partially applied arguments.
     *
     * **Note:** This method doesn't set the "length" property of partially
     * applied functions.
     *
     * @static
     * @memberOf _
     * @since 1.0.0
     * @category Function
     * @param {Function} func The function to partially apply arguments to.
     * @param {...*} [partials] The arguments to be partially applied.
     * @returns {Function} Returns the new partially applied function.
     * @example
     *
     * function greet(greeting, name) {
     *   return greeting + ' ' + name;
     * }
     *
     * var greetFred = _.partialRight(greet, 'fred');
     * greetFred('hi');
     * // => 'hi fred'
     *
     * // Partially applied with placeholders.
     * var sayHelloTo = _.partialRight(greet, 'hello', _);
     * sayHelloTo('fred');
     * // => 'hello fred'
     */
    var partialRight = baseRest(function(func, partials) {
      var holders = replaceHolders(partials, getHolder(partialRight));
      return createWrap(func, WRAP_PARTIAL_RIGHT_FLAG, undefined, partials, holders);
    });

    /**
     * Creates a function that invokes `func` with arguments arranged according
     * to the specified `indexes` where the argument value at the first index is
     * provided as the first argument, the argument value at the second index is
     * provided as the second argument, and so on.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Function
     * @param {Function} func The function to rearrange arguments for.
     * @param {...(number|number[])} indexes The arranged argument indexes.
     * @returns {Function} Returns the new function.
     * @example
     *
     * var rearged = _.rearg(function(a, b, c) {
     *   return [a, b, c];
     * }, [2, 0, 1]);
     *
     * rearged('b', 'c', 'a')
     * // => ['a', 'b', 'c']
     */
    var rearg = flatRest(function(func, indexes) {
      return createWrap(func, WRAP_REARG_FLAG, undefined, undefined, undefined, indexes);
    });

    /**
     * Creates a function that invokes `func` with the `this` binding of the
     * created function and arguments from `start` and beyond provided as
     * an array.
     *
     * **Note:** This method is based on the
     * [rest parameter](https://mdn.io/rest_parameters).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Function
     * @param {Function} func The function to apply a rest parameter to.
     * @param {number} [start=func.length-1] The start position of the rest parameter.
     * @returns {Function} Returns the new function.
     * @example
     *
     * var say = _.rest(function(what, names) {
     *   return what + ' ' + _.initial(names).join(', ') +
     *     (_.size(names) > 1 ? ', & ' : '') + _.last(names);
     * });
     *
     * say('hello', 'fred', 'barney', 'pebbles');
     * // => 'hello fred, barney, & pebbles'
     */
    function rest(func, start) {
      if (typeof func != 'function') {
        throw new TypeError(FUNC_ERROR_TEXT);
      }
      start = start === undefined ? start : toInteger(start);
      return baseRest(func, start);
    }

    /**
     * Creates a function that invokes `func` with the `this` binding of the
     * create function and an array of arguments much like
     * [`Function#apply`](http://www.ecma-international.org/ecma-262/7.0/#sec-function.prototype.apply).
     *
     * **Note:** This method is based on the
     * [spread operator](https://mdn.io/spread_operator).
     *
     * @static
     * @memberOf _
     * @since 3.2.0
     * @category Function
     * @param {Function} func The function to spread arguments over.
     * @param {number} [start=0] The start position of the spread.
     * @returns {Function} Returns the new function.
     * @example
     *
     * var say = _.spread(function(who, what) {
     *   return who + ' says ' + what;
     * });
     *
     * say(['fred', 'hello']);
     * // => 'fred says hello'
     *
     * var numbers = Promise.all([
     *   Promise.resolve(40),
     *   Promise.resolve(36)
     * ]);
     *
     * numbers.then(_.spread(function(x, y) {
     *   return x + y;
     * }));
     * // => a Promise of 76
     */
    function spread(func, start) {
      if (typeof func != 'function') {
        throw new TypeError(FUNC_ERROR_TEXT);
      }
      start = start == null ? 0 : nativeMax(toInteger(start), 0);
      return baseRest(function(args) {
        var array = args[start],
            otherArgs = castSlice(args, 0, start);

        if (array) {
          arrayPush(otherArgs, array);
        }
        return apply(func, this, otherArgs);
      });
    }

    /**
     * Creates a throttled function that only invokes `func` at most once per
     * every `wait` milliseconds. The throttled function comes with a `cancel`
     * method to cancel delayed `func` invocations and a `flush` method to
     * immediately invoke them. Provide `options` to indicate whether `func`
     * should be invoked on the leading and/or trailing edge of the `wait`
     * timeout. The `func` is invoked with the last arguments provided to the
     * throttled function. Subsequent calls to the throttled function return the
     * result of the last `func` invocation.
     *
     * **Note:** If `leading` and `trailing` options are `true`, `func` is
     * invoked on the trailing edge of the timeout only if the throttled function
     * is invoked more than once during the `wait` timeout.
     *
     * If `wait` is `0` and `leading` is `false`, `func` invocation is deferred
     * until to the next tick, similar to `setTimeout` with a timeout of `0`.
     *
     * See [David Corbacho's article](https://css-tricks.com/debouncing-throttling-explained-examples/)
     * for details over the differences between `_.throttle` and `_.debounce`.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Function
     * @param {Function} func The function to throttle.
     * @param {number} [wait=0] The number of milliseconds to throttle invocations to.
     * @param {Object} [options={}] The options object.
     * @param {boolean} [options.leading=true]
     *  Specify invoking on the leading edge of the timeout.
     * @param {boolean} [options.trailing=true]
     *  Specify invoking on the trailing edge of the timeout.
     * @returns {Function} Returns the new throttled function.
     * @example
     *
     * // Avoid excessively updating the position while scrolling.
     * jQuery(window).on('scroll', _.throttle(updatePosition, 100));
     *
     * // Invoke `renewToken` when the click event is fired, but not more than once every 5 minutes.
     * var throttled = _.throttle(renewToken, 300000, { 'trailing': false });
     * jQuery(element).on('click', throttled);
     *
     * // Cancel the trailing throttled invocation.
     * jQuery(window).on('popstate', throttled.cancel);
     */
    function throttle(func, wait, options) {
      var leading = true,
          trailing = true;

      if (typeof func != 'function') {
        throw new TypeError(FUNC_ERROR_TEXT);
      }
      if (isObject(options)) {
        leading = 'leading' in options ? !!options.leading : leading;
        trailing = 'trailing' in options ? !!options.trailing : trailing;
      }
      return debounce(func, wait, {
        'leading': leading,
        'maxWait': wait,
        'trailing': trailing
      });
    }

    /**
     * Creates a function that accepts up to one argument, ignoring any
     * additional arguments.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Function
     * @param {Function} func The function to cap arguments for.
     * @returns {Function} Returns the new capped function.
     * @example
     *
     * _.map(['6', '8', '10'], _.unary(parseInt));
     * // => [6, 8, 10]
     */
    function unary(func) {
      return ary(func, 1);
    }

    /**
     * Creates a function that provides `value` to `wrapper` as its first
     * argument. Any additional arguments provided to the function are appended
     * to those provided to the `wrapper`. The wrapper is invoked with the `this`
     * binding of the created function.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Function
     * @param {*} value The value to wrap.
     * @param {Function} [wrapper=identity] The wrapper function.
     * @returns {Function} Returns the new function.
     * @example
     *
     * var p = _.wrap(_.escape, function(func, text) {
     *   return '<p>' + func(text) + '</p>';
     * });
     *
     * p('fred, barney, & pebbles');
     * // => '<p>fred, barney, &amp; pebbles</p>'
     */
    function wrap(value, wrapper) {
      return partial(castFunction(wrapper), value);
    }

    /*------------------------------------------------------------------------*/

    /**
     * Casts `value` as an array if it's not one.
     *
     * @static
     * @memberOf _
     * @since 4.4.0
     * @category Lang
     * @param {*} value The value to inspect.
     * @returns {Array} Returns the cast array.
     * @example
     *
     * _.castArray(1);
     * // => [1]
     *
     * _.castArray({ 'a': 1 });
     * // => [{ 'a': 1 }]
     *
     * _.castArray('abc');
     * // => ['abc']
     *
     * _.castArray(null);
     * // => [null]
     *
     * _.castArray(undefined);
     * // => [undefined]
     *
     * _.castArray();
     * // => []
     *
     * var array = [1, 2, 3];
     * console.log(_.castArray(array) === array);
     * // => true
     */
    function castArray() {
      if (!arguments.length) {
        return [];
      }
      var value = arguments[0];
      return isArray(value) ? value : [value];
    }

    /**
     * Creates a shallow clone of `value`.
     *
     * **Note:** This method is loosely based on the
     * [structured clone algorithm](https://mdn.io/Structured_clone_algorithm)
     * and supports cloning arrays, array buffers, booleans, date objects, maps,
     * numbers, `Object` objects, regexes, sets, strings, symbols, and typed
     * arrays. The own enumerable properties of `arguments` objects are cloned
     * as plain objects. An empty object is returned for uncloneable values such
     * as error objects, functions, DOM nodes, and WeakMaps.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Lang
     * @param {*} value The value to clone.
     * @returns {*} Returns the cloned value.
     * @see _.cloneDeep
     * @example
     *
     * var objects = [{ 'a': 1 }, { 'b': 2 }];
     *
     * var shallow = _.clone(objects);
     * console.log(shallow[0] === objects[0]);
     * // => true
     */
    function clone(value) {
      return baseClone(value, CLONE_SYMBOLS_FLAG);
    }

    /**
     * This method is like `_.clone` except that it accepts `customizer` which
     * is invoked to produce the cloned value. If `customizer` returns `undefined`,
     * cloning is handled by the method instead. The `customizer` is invoked with
     * up to four arguments; (value [, index|key, object, stack]).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Lang
     * @param {*} value The value to clone.
     * @param {Function} [customizer] The function to customize cloning.
     * @returns {*} Returns the cloned value.
     * @see _.cloneDeepWith
     * @example
     *
     * function customizer(value) {
     *   if (_.isElement(value)) {
     *     return value.cloneNode(false);
     *   }
     * }
     *
     * var el = _.cloneWith(document.body, customizer);
     *
     * console.log(el === document.body);
     * // => false
     * console.log(el.nodeName);
     * // => 'BODY'
     * console.log(el.childNodes.length);
     * // => 0
     */
    function cloneWith(value, customizer) {
      customizer = typeof customizer == 'function' ? customizer : undefined;
      return baseClone(value, CLONE_SYMBOLS_FLAG, customizer);
    }

    /**
     * This method is like `_.clone` except that it recursively clones `value`.
     *
     * @static
     * @memberOf _
     * @since 1.0.0
     * @category Lang
     * @param {*} value The value to recursively clone.
     * @returns {*} Returns the deep cloned value.
     * @see _.clone
     * @example
     *
     * var objects = [{ 'a': 1 }, { 'b': 2 }];
     *
     * var deep = _.cloneDeep(objects);
     * console.log(deep[0] === objects[0]);
     * // => false
     */
    function cloneDeep(value) {
      return baseClone(value, CLONE_DEEP_FLAG | CLONE_SYMBOLS_FLAG);
    }

    /**
     * This method is like `_.cloneWith` except that it recursively clones `value`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Lang
     * @param {*} value The value to recursively clone.
     * @param {Function} [customizer] The function to customize cloning.
     * @returns {*} Returns the deep cloned value.
     * @see _.cloneWith
     * @example
     *
     * function customizer(value) {
     *   if (_.isElement(value)) {
     *     return value.cloneNode(true);
     *   }
     * }
     *
     * var el = _.cloneDeepWith(document.body, customizer);
     *
     * console.log(el === document.body);
     * // => false
     * console.log(el.nodeName);
     * // => 'BODY'
     * console.log(el.childNodes.length);
     * // => 20
     */
    function cloneDeepWith(value, customizer) {
      customizer = typeof customizer == 'function' ? customizer : undefined;
      return baseClone(value, CLONE_DEEP_FLAG | CLONE_SYMBOLS_FLAG, customizer);
    }

    /**
     * Checks if `object` conforms to `source` by invoking the predicate
     * properties of `source` with the corresponding property values of `object`.
     *
     * **Note:** This method is equivalent to `_.conforms` when `source` is
     * partially applied.
     *
     * @static
     * @memberOf _
     * @since 4.14.0
     * @category Lang
     * @param {Object} object The object to inspect.
     * @param {Object} source The object of property predicates to conform to.
     * @returns {boolean} Returns `true` if `object` conforms, else `false`.
     * @example
     *
     * var object = { 'a': 1, 'b': 2 };
     *
     * _.conformsTo(object, { 'b': function(n) { return n > 1; } });
     * // => true
     *
     * _.conformsTo(object, { 'b': function(n) { return n > 2; } });
     * // => false
     */
    function conformsTo(object, source) {
      return source == null || baseConformsTo(object, source, keys(source));
    }

    /**
     * Performs a
     * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
     * comparison between two values to determine if they are equivalent.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Lang
     * @param {*} value The value to compare.
     * @param {*} other The other value to compare.
     * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
     * @example
     *
     * var object = { 'a': 1 };
     * var other = { 'a': 1 };
     *
     * _.eq(object, object);
     * // => true
     *
     * _.eq(object, other);
     * // => false
     *
     * _.eq('a', 'a');
     * // => true
     *
     * _.eq('a', Object('a'));
     * // => false
     *
     * _.eq(NaN, NaN);
     * // => true
     */
    function eq(value, other) {
      return value === other || (value !== value && other !== other);
    }

    /**
     * Checks if `value` is greater than `other`.
     *
     * @static
     * @memberOf _
     * @since 3.9.0
     * @category Lang
     * @param {*} value The value to compare.
     * @param {*} other The other value to compare.
     * @returns {boolean} Returns `true` if `value` is greater than `other`,
     *  else `false`.
     * @see _.lt
     * @example
     *
     * _.gt(3, 1);
     * // => true
     *
     * _.gt(3, 3);
     * // => false
     *
     * _.gt(1, 3);
     * // => false
     */
    var gt = createRelationalOperation(baseGt);

    /**
     * Checks if `value` is greater than or equal to `other`.
     *
     * @static
     * @memberOf _
     * @since 3.9.0
     * @category Lang
     * @param {*} value The value to compare.
     * @param {*} other The other value to compare.
     * @returns {boolean} Returns `true` if `value` is greater than or equal to
     *  `other`, else `false`.
     * @see _.lte
     * @example
     *
     * _.gte(3, 1);
     * // => true
     *
     * _.gte(3, 3);
     * // => true
     *
     * _.gte(1, 3);
     * // => false
     */
    var gte = createRelationalOperation(function(value, other) {
      return value >= other;
    });

    /**
     * Checks if `value` is likely an `arguments` object.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is an `arguments` object,
     *  else `false`.
     * @example
     *
     * _.isArguments(function() { return arguments; }());
     * // => true
     *
     * _.isArguments([1, 2, 3]);
     * // => false
     */
    var isArguments = baseIsArguments(function() { return arguments; }()) ? baseIsArguments : function(value) {
      return isObjectLike(value) && hasOwnProperty.call(value, 'callee') &&
        !propertyIsEnumerable.call(value, 'callee');
    };

    /**
     * Checks if `value` is classified as an `Array` object.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is an array, else `false`.
     * @example
     *
     * _.isArray([1, 2, 3]);
     * // => true
     *
     * _.isArray(document.body.children);
     * // => false
     *
     * _.isArray('abc');
     * // => false
     *
     * _.isArray(_.noop);
     * // => false
     */
    var isArray = Array.isArray;

    /**
     * Checks if `value` is classified as an `ArrayBuffer` object.
     *
     * @static
     * @memberOf _
     * @since 4.3.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is an array buffer, else `false`.
     * @example
     *
     * _.isArrayBuffer(new ArrayBuffer(2));
     * // => true
     *
     * _.isArrayBuffer(new Array(2));
     * // => false
     */
    var isArrayBuffer = nodeIsArrayBuffer ? baseUnary(nodeIsArrayBuffer) : baseIsArrayBuffer;

    /**
     * Checks if `value` is array-like. A value is considered array-like if it's
     * not a function and has a `value.length` that's an integer greater than or
     * equal to `0` and less than or equal to `Number.MAX_SAFE_INTEGER`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is array-like, else `false`.
     * @example
     *
     * _.isArrayLike([1, 2, 3]);
     * // => true
     *
     * _.isArrayLike(document.body.children);
     * // => true
     *
     * _.isArrayLike('abc');
     * // => true
     *
     * _.isArrayLike(_.noop);
     * // => false
     */
    function isArrayLike(value) {
      return value != null && isLength(value.length) && !isFunction(value);
    }

    /**
     * This method is like `_.isArrayLike` except that it also checks if `value`
     * is an object.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is an array-like object,
     *  else `false`.
     * @example
     *
     * _.isArrayLikeObject([1, 2, 3]);
     * // => true
     *
     * _.isArrayLikeObject(document.body.children);
     * // => true
     *
     * _.isArrayLikeObject('abc');
     * // => false
     *
     * _.isArrayLikeObject(_.noop);
     * // => false
     */
    function isArrayLikeObject(value) {
      return isObjectLike(value) && isArrayLike(value);
    }

    /**
     * Checks if `value` is classified as a boolean primitive or object.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a boolean, else `false`.
     * @example
     *
     * _.isBoolean(false);
     * // => true
     *
     * _.isBoolean(null);
     * // => false
     */
    function isBoolean(value) {
      return value === true || value === false ||
        (isObjectLike(value) && baseGetTag(value) == boolTag);
    }

    /**
     * Checks if `value` is a buffer.
     *
     * @static
     * @memberOf _
     * @since 4.3.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a buffer, else `false`.
     * @example
     *
     * _.isBuffer(new Buffer(2));
     * // => true
     *
     * _.isBuffer(new Uint8Array(2));
     * // => false
     */
    var isBuffer = nativeIsBuffer || stubFalse;

    /**
     * Checks if `value` is classified as a `Date` object.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a date object, else `false`.
     * @example
     *
     * _.isDate(new Date);
     * // => true
     *
     * _.isDate('Mon April 23 2012');
     * // => false
     */
    var isDate = nodeIsDate ? baseUnary(nodeIsDate) : baseIsDate;

    /**
     * Checks if `value` is likely a DOM element.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a DOM element, else `false`.
     * @example
     *
     * _.isElement(document.body);
     * // => true
     *
     * _.isElement('<body>');
     * // => false
     */
    function isElement(value) {
      return isObjectLike(value) && value.nodeType === 1 && !isPlainObject(value);
    }

    /**
     * Checks if `value` is an empty object, collection, map, or set.
     *
     * Objects are considered empty if they have no own enumerable string keyed
     * properties.
     *
     * Array-like values such as `arguments` objects, arrays, buffers, strings, or
     * jQuery-like collections are considered empty if they have a `length` of `0`.
     * Similarly, maps and sets are considered empty if they have a `size` of `0`.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is empty, else `false`.
     * @example
     *
     * _.isEmpty(null);
     * // => true
     *
     * _.isEmpty(true);
     * // => true
     *
     * _.isEmpty(1);
     * // => true
     *
     * _.isEmpty([1, 2, 3]);
     * // => false
     *
     * _.isEmpty({ 'a': 1 });
     * // => false
     */
    function isEmpty(value) {
      if (value == null) {
        return true;
      }
      if (isArrayLike(value) &&
          (isArray(value) || typeof value == 'string' || typeof value.splice == 'function' ||
            isBuffer(value) || isTypedArray(value) || isArguments(value))) {
        return !value.length;
      }
      var tag = getTag(value);
      if (tag == mapTag || tag == setTag) {
        return !value.size;
      }
      if (isPrototype(value)) {
        return !baseKeys(value).length;
      }
      for (var key in value) {
        if (hasOwnProperty.call(value, key)) {
          return false;
        }
      }
      return true;
    }

    /**
     * Performs a deep comparison between two values to determine if they are
     * equivalent.
     *
     * **Note:** This method supports comparing arrays, array buffers, booleans,
     * date objects, error objects, maps, numbers, `Object` objects, regexes,
     * sets, strings, symbols, and typed arrays. `Object` objects are compared
     * by their own, not inherited, enumerable properties. Functions and DOM
     * nodes are compared by strict equality, i.e. `===`.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Lang
     * @param {*} value The value to compare.
     * @param {*} other The other value to compare.
     * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
     * @example
     *
     * var object = { 'a': 1 };
     * var other = { 'a': 1 };
     *
     * _.isEqual(object, other);
     * // => true
     *
     * object === other;
     * // => false
     */
    function isEqual(value, other) {
      return baseIsEqual(value, other);
    }

    /**
     * This method is like `_.isEqual` except that it accepts `customizer` which
     * is invoked to compare values. If `customizer` returns `undefined`, comparisons
     * are handled by the method instead. The `customizer` is invoked with up to
     * six arguments: (objValue, othValue [, index|key, object, other, stack]).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Lang
     * @param {*} value The value to compare.
     * @param {*} other The other value to compare.
     * @param {Function} [customizer] The function to customize comparisons.
     * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
     * @example
     *
     * function isGreeting(value) {
     *   return /^h(?:i|ello)$/.test(value);
     * }
     *
     * function customizer(objValue, othValue) {
     *   if (isGreeting(objValue) && isGreeting(othValue)) {
     *     return true;
     *   }
     * }
     *
     * var array = ['hello', 'goodbye'];
     * var other = ['hi', 'goodbye'];
     *
     * _.isEqualWith(array, other, customizer);
     * // => true
     */
    function isEqualWith(value, other, customizer) {
      customizer = typeof customizer == 'function' ? customizer : undefined;
      var result = customizer ? customizer(value, other) : undefined;
      return result === undefined ? baseIsEqual(value, other, undefined, customizer) : !!result;
    }

    /**
     * Checks if `value` is an `Error`, `EvalError`, `RangeError`, `ReferenceError`,
     * `SyntaxError`, `TypeError`, or `URIError` object.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is an error object, else `false`.
     * @example
     *
     * _.isError(new Error);
     * // => true
     *
     * _.isError(Error);
     * // => false
     */
    function isError(value) {
      if (!isObjectLike(value)) {
        return false;
      }
      var tag = baseGetTag(value);
      return tag == errorTag || tag == domExcTag ||
        (typeof value.message == 'string' && typeof value.name == 'string' && !isPlainObject(value));
    }

    /**
     * Checks if `value` is a finite primitive number.
     *
     * **Note:** This method is based on
     * [`Number.isFinite`](https://mdn.io/Number/isFinite).
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a finite number, else `false`.
     * @example
     *
     * _.isFinite(3);
     * // => true
     *
     * _.isFinite(Number.MIN_VALUE);
     * // => true
     *
     * _.isFinite(Infinity);
     * // => false
     *
     * _.isFinite('3');
     * // => false
     */
    function isFinite(value) {
      return typeof value == 'number' && nativeIsFinite(value);
    }

    /**
     * Checks if `value` is classified as a `Function` object.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a function, else `false`.
     * @example
     *
     * _.isFunction(_);
     * // => true
     *
     * _.isFunction(/abc/);
     * // => false
     */
    function isFunction(value) {
      if (!isObject(value)) {
        return false;
      }
      // The use of `Object#toString` avoids issues with the `typeof` operator
      // in Safari 9 which returns 'object' for typed arrays and other constructors.
      var tag = baseGetTag(value);
      return tag == funcTag || tag == genTag || tag == asyncTag || tag == proxyTag;
    }

    /**
     * Checks if `value` is an integer.
     *
     * **Note:** This method is based on
     * [`Number.isInteger`](https://mdn.io/Number/isInteger).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is an integer, else `false`.
     * @example
     *
     * _.isInteger(3);
     * // => true
     *
     * _.isInteger(Number.MIN_VALUE);
     * // => false
     *
     * _.isInteger(Infinity);
     * // => false
     *
     * _.isInteger('3');
     * // => false
     */
    function isInteger(value) {
      return typeof value == 'number' && value == toInteger(value);
    }

    /**
     * Checks if `value` is a valid array-like length.
     *
     * **Note:** This method is loosely based on
     * [`ToLength`](http://ecma-international.org/ecma-262/7.0/#sec-tolength).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a valid length, else `false`.
     * @example
     *
     * _.isLength(3);
     * // => true
     *
     * _.isLength(Number.MIN_VALUE);
     * // => false
     *
     * _.isLength(Infinity);
     * // => false
     *
     * _.isLength('3');
     * // => false
     */
    function isLength(value) {
      return typeof value == 'number' &&
        value > -1 && value % 1 == 0 && value <= MAX_SAFE_INTEGER;
    }

    /**
     * Checks if `value` is the
     * [language type](http://www.ecma-international.org/ecma-262/7.0/#sec-ecmascript-language-types)
     * of `Object`. (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`)
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is an object, else `false`.
     * @example
     *
     * _.isObject({});
     * // => true
     *
     * _.isObject([1, 2, 3]);
     * // => true
     *
     * _.isObject(_.noop);
     * // => true
     *
     * _.isObject(null);
     * // => false
     */
    function isObject(value) {
      var type = typeof value;
      return value != null && (type == 'object' || type == 'function');
    }

    /**
     * Checks if `value` is object-like. A value is object-like if it's not `null`
     * and has a `typeof` result of "object".
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is object-like, else `false`.
     * @example
     *
     * _.isObjectLike({});
     * // => true
     *
     * _.isObjectLike([1, 2, 3]);
     * // => true
     *
     * _.isObjectLike(_.noop);
     * // => false
     *
     * _.isObjectLike(null);
     * // => false
     */
    function isObjectLike(value) {
      return value != null && typeof value == 'object';
    }

    /**
     * Checks if `value` is classified as a `Map` object.
     *
     * @static
     * @memberOf _
     * @since 4.3.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a map, else `false`.
     * @example
     *
     * _.isMap(new Map);
     * // => true
     *
     * _.isMap(new WeakMap);
     * // => false
     */
    var isMap = nodeIsMap ? baseUnary(nodeIsMap) : baseIsMap;

    /**
     * Performs a partial deep comparison between `object` and `source` to
     * determine if `object` contains equivalent property values.
     *
     * **Note:** This method is equivalent to `_.matches` when `source` is
     * partially applied.
     *
     * Partial comparisons will match empty array and empty object `source`
     * values against any array or object value, respectively. See `_.isEqual`
     * for a list of supported value comparisons.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Lang
     * @param {Object} object The object to inspect.
     * @param {Object} source The object of property values to match.
     * @returns {boolean} Returns `true` if `object` is a match, else `false`.
     * @example
     *
     * var object = { 'a': 1, 'b': 2 };
     *
     * _.isMatch(object, { 'b': 2 });
     * // => true
     *
     * _.isMatch(object, { 'b': 1 });
     * // => false
     */
    function isMatch(object, source) {
      return object === source || baseIsMatch(object, source, getMatchData(source));
    }

    /**
     * This method is like `_.isMatch` except that it accepts `customizer` which
     * is invoked to compare values. If `customizer` returns `undefined`, comparisons
     * are handled by the method instead. The `customizer` is invoked with five
     * arguments: (objValue, srcValue, index|key, object, source).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Lang
     * @param {Object} object The object to inspect.
     * @param {Object} source The object of property values to match.
     * @param {Function} [customizer] The function to customize comparisons.
     * @returns {boolean} Returns `true` if `object` is a match, else `false`.
     * @example
     *
     * function isGreeting(value) {
     *   return /^h(?:i|ello)$/.test(value);
     * }
     *
     * function customizer(objValue, srcValue) {
     *   if (isGreeting(objValue) && isGreeting(srcValue)) {
     *     return true;
     *   }
     * }
     *
     * var object = { 'greeting': 'hello' };
     * var source = { 'greeting': 'hi' };
     *
     * _.isMatchWith(object, source, customizer);
     * // => true
     */
    function isMatchWith(object, source, customizer) {
      customizer = typeof customizer == 'function' ? customizer : undefined;
      return baseIsMatch(object, source, getMatchData(source), customizer);
    }

    /**
     * Checks if `value` is `NaN`.
     *
     * **Note:** This method is based on
     * [`Number.isNaN`](https://mdn.io/Number/isNaN) and is not the same as
     * global [`isNaN`](https://mdn.io/isNaN) which returns `true` for
     * `undefined` and other non-number values.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is `NaN`, else `false`.
     * @example
     *
     * _.isNaN(NaN);
     * // => true
     *
     * _.isNaN(new Number(NaN));
     * // => true
     *
     * isNaN(undefined);
     * // => true
     *
     * _.isNaN(undefined);
     * // => false
     */
    function isNaN(value) {
      // An `NaN` primitive is the only value that is not equal to itself.
      // Perform the `toStringTag` check first to avoid errors with some
      // ActiveX objects in IE.
      return isNumber(value) && value != +value;
    }

    /**
     * Checks if `value` is a pristine native function.
     *
     * **Note:** This method can't reliably detect native functions in the presence
     * of the core-js package because core-js circumvents this kind of detection.
     * Despite multiple requests, the core-js maintainer has made it clear: any
     * attempt to fix the detection will be obstructed. As a result, we're left
     * with little choice but to throw an error. Unfortunately, this also affects
     * packages, like [babel-polyfill](https://www.npmjs.com/package/babel-polyfill),
     * which rely on core-js.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a native function,
     *  else `false`.
     * @example
     *
     * _.isNative(Array.prototype.push);
     * // => true
     *
     * _.isNative(_);
     * // => false
     */
    function isNative(value) {
      if (isMaskable(value)) {
        throw new Error(CORE_ERROR_TEXT);
      }
      return baseIsNative(value);
    }

    /**
     * Checks if `value` is `null`.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is `null`, else `false`.
     * @example
     *
     * _.isNull(null);
     * // => true
     *
     * _.isNull(void 0);
     * // => false
     */
    function isNull(value) {
      return value === null;
    }

    /**
     * Checks if `value` is `null` or `undefined`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is nullish, else `false`.
     * @example
     *
     * _.isNil(null);
     * // => true
     *
     * _.isNil(void 0);
     * // => true
     *
     * _.isNil(NaN);
     * // => false
     */
    function isNil(value) {
      return value == null;
    }

    /**
     * Checks if `value` is classified as a `Number` primitive or object.
     *
     * **Note:** To exclude `Infinity`, `-Infinity`, and `NaN`, which are
     * classified as numbers, use the `_.isFinite` method.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a number, else `false`.
     * @example
     *
     * _.isNumber(3);
     * // => true
     *
     * _.isNumber(Number.MIN_VALUE);
     * // => true
     *
     * _.isNumber(Infinity);
     * // => true
     *
     * _.isNumber('3');
     * // => false
     */
    function isNumber(value) {
      return typeof value == 'number' ||
        (isObjectLike(value) && baseGetTag(value) == numberTag);
    }

    /**
     * Checks if `value` is a plain object, that is, an object created by the
     * `Object` constructor or one with a `[[Prototype]]` of `null`.
     *
     * @static
     * @memberOf _
     * @since 0.8.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a plain object, else `false`.
     * @example
     *
     * function Foo() {
     *   this.a = 1;
     * }
     *
     * _.isPlainObject(new Foo);
     * // => false
     *
     * _.isPlainObject([1, 2, 3]);
     * // => false
     *
     * _.isPlainObject({ 'x': 0, 'y': 0 });
     * // => true
     *
     * _.isPlainObject(Object.create(null));
     * // => true
     */
    function isPlainObject(value) {
      if (!isObjectLike(value) || baseGetTag(value) != objectTag) {
        return false;
      }
      var proto = getPrototype(value);
      if (proto === null) {
        return true;
      }
      var Ctor = hasOwnProperty.call(proto, 'constructor') && proto.constructor;
      return typeof Ctor == 'function' && Ctor instanceof Ctor &&
        funcToString.call(Ctor) == objectCtorString;
    }

    /**
     * Checks if `value` is classified as a `RegExp` object.
     *
     * @static
     * @memberOf _
     * @since 0.1.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a regexp, else `false`.
     * @example
     *
     * _.isRegExp(/abc/);
     * // => true
     *
     * _.isRegExp('/abc/');
     * // => false
     */
    var isRegExp = nodeIsRegExp ? baseUnary(nodeIsRegExp) : baseIsRegExp;

    /**
     * Checks if `value` is a safe integer. An integer is safe if it's an IEEE-754
     * double precision number which isn't the result of a rounded unsafe integer.
     *
     * **Note:** This method is based on
     * [`Number.isSafeInteger`](https://mdn.io/Number/isSafeInteger).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a safe integer, else `false`.
     * @example
     *
     * _.isSafeInteger(3);
     * // => true
     *
     * _.isSafeInteger(Number.MIN_VALUE);
     * // => false
     *
     * _.isSafeInteger(Infinity);
     * // => false
     *
     * _.isSafeInteger('3');
     * // => false
     */
    function isSafeInteger(value) {
      return isInteger(value) && value >= -MAX_SAFE_INTEGER && value <= MAX_SAFE_INTEGER;
    }

    /**
     * Checks if `value` is classified as a `Set` object.
     *
     * @static
     * @memberOf _
     * @since 4.3.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a set, else `false`.
     * @example
     *
     * _.isSet(new Set);
     * // => true
     *
     * _.isSet(new WeakSet);
     * // => false
     */
    var isSet = nodeIsSet ? baseUnary(nodeIsSet) : baseIsSet;

    /**
     * Checks if `value` is classified as a `String` primitive or object.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a string, else `false`.
     * @example
     *
     * _.isString('abc');
     * // => true
     *
     * _.isString(1);
     * // => false
     */
    function isString(value) {
      return typeof value == 'string' ||
        (!isArray(value) && isObjectLike(value) && baseGetTag(value) == stringTag);
    }

    /**
     * Checks if `value` is classified as a `Symbol` primitive or object.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a symbol, else `false`.
     * @example
     *
     * _.isSymbol(Symbol.iterator);
     * // => true
     *
     * _.isSymbol('abc');
     * // => false
     */
    function isSymbol(value) {
      return typeof value == 'symbol' ||
        (isObjectLike(value) && baseGetTag(value) == symbolTag);
    }

    /**
     * Checks if `value` is classified as a typed array.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a typed array, else `false`.
     * @example
     *
     * _.isTypedArray(new Uint8Array);
     * // => true
     *
     * _.isTypedArray([]);
     * // => false
     */
    var isTypedArray = nodeIsTypedArray ? baseUnary(nodeIsTypedArray) : baseIsTypedArray;

    /**
     * Checks if `value` is `undefined`.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is `undefined`, else `false`.
     * @example
     *
     * _.isUndefined(void 0);
     * // => true
     *
     * _.isUndefined(null);
     * // => false
     */
    function isUndefined(value) {
      return value === undefined;
    }

    /**
     * Checks if `value` is classified as a `WeakMap` object.
     *
     * @static
     * @memberOf _
     * @since 4.3.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a weak map, else `false`.
     * @example
     *
     * _.isWeakMap(new WeakMap);
     * // => true
     *
     * _.isWeakMap(new Map);
     * // => false
     */
    function isWeakMap(value) {
      return isObjectLike(value) && getTag(value) == weakMapTag;
    }

    /**
     * Checks if `value` is classified as a `WeakSet` object.
     *
     * @static
     * @memberOf _
     * @since 4.3.0
     * @category Lang
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a weak set, else `false`.
     * @example
     *
     * _.isWeakSet(new WeakSet);
     * // => true
     *
     * _.isWeakSet(new Set);
     * // => false
     */
    function isWeakSet(value) {
      return isObjectLike(value) && baseGetTag(value) == weakSetTag;
    }

    /**
     * Checks if `value` is less than `other`.
     *
     * @static
     * @memberOf _
     * @since 3.9.0
     * @category Lang
     * @param {*} value The value to compare.
     * @param {*} other The other value to compare.
     * @returns {boolean} Returns `true` if `value` is less than `other`,
     *  else `false`.
     * @see _.gt
     * @example
     *
     * _.lt(1, 3);
     * // => true
     *
     * _.lt(3, 3);
     * // => false
     *
     * _.lt(3, 1);
     * // => false
     */
    var lt = createRelationalOperation(baseLt);

    /**
     * Checks if `value` is less than or equal to `other`.
     *
     * @static
     * @memberOf _
     * @since 3.9.0
     * @category Lang
     * @param {*} value The value to compare.
     * @param {*} other The other value to compare.
     * @returns {boolean} Returns `true` if `value` is less than or equal to
     *  `other`, else `false`.
     * @see _.gte
     * @example
     *
     * _.lte(1, 3);
     * // => true
     *
     * _.lte(3, 3);
     * // => true
     *
     * _.lte(3, 1);
     * // => false
     */
    var lte = createRelationalOperation(function(value, other) {
      return value <= other;
    });

    /**
     * Converts `value` to an array.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Lang
     * @param {*} value The value to convert.
     * @returns {Array} Returns the converted array.
     * @example
     *
     * _.toArray({ 'a': 1, 'b': 2 });
     * // => [1, 2]
     *
     * _.toArray('abc');
     * // => ['a', 'b', 'c']
     *
     * _.toArray(1);
     * // => []
     *
     * _.toArray(null);
     * // => []
     */
    function toArray(value) {
      if (!value) {
        return [];
      }
      if (isArrayLike(value)) {
        return isString(value) ? stringToArray(value) : copyArray(value);
      }
      if (symIterator && value[symIterator]) {
        return iteratorToArray(value[symIterator]());
      }
      var tag = getTag(value),
          func = tag == mapTag ? mapToArray : (tag == setTag ? setToArray : values);

      return func(value);
    }

    /**
     * Converts `value` to a finite number.
     *
     * @static
     * @memberOf _
     * @since 4.12.0
     * @category Lang
     * @param {*} value The value to convert.
     * @returns {number} Returns the converted number.
     * @example
     *
     * _.toFinite(3.2);
     * // => 3.2
     *
     * _.toFinite(Number.MIN_VALUE);
     * // => 5e-324
     *
     * _.toFinite(Infinity);
     * // => 1.7976931348623157e+308
     *
     * _.toFinite('3.2');
     * // => 3.2
     */
    function toFinite(value) {
      if (!value) {
        return value === 0 ? value : 0;
      }
      value = toNumber(value);
      if (value === INFINITY || value === -INFINITY) {
        var sign = (value < 0 ? -1 : 1);
        return sign * MAX_INTEGER;
      }
      return value === value ? value : 0;
    }

    /**
     * Converts `value` to an integer.
     *
     * **Note:** This method is loosely based on
     * [`ToInteger`](http://www.ecma-international.org/ecma-262/7.0/#sec-tointeger).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Lang
     * @param {*} value The value to convert.
     * @returns {number} Returns the converted integer.
     * @example
     *
     * _.toInteger(3.2);
     * // => 3
     *
     * _.toInteger(Number.MIN_VALUE);
     * // => 0
     *
     * _.toInteger(Infinity);
     * // => 1.7976931348623157e+308
     *
     * _.toInteger('3.2');
     * // => 3
     */
    function toInteger(value) {
      var result = toFinite(value),
          remainder = result % 1;

      return result === result ? (remainder ? result - remainder : result) : 0;
    }

    /**
     * Converts `value` to an integer suitable for use as the length of an
     * array-like object.
     *
     * **Note:** This method is based on
     * [`ToLength`](http://ecma-international.org/ecma-262/7.0/#sec-tolength).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Lang
     * @param {*} value The value to convert.
     * @returns {number} Returns the converted integer.
     * @example
     *
     * _.toLength(3.2);
     * // => 3
     *
     * _.toLength(Number.MIN_VALUE);
     * // => 0
     *
     * _.toLength(Infinity);
     * // => 4294967295
     *
     * _.toLength('3.2');
     * // => 3
     */
    function toLength(value) {
      return value ? baseClamp(toInteger(value), 0, MAX_ARRAY_LENGTH) : 0;
    }

    /**
     * Converts `value` to a number.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Lang
     * @param {*} value The value to process.
     * @returns {number} Returns the number.
     * @example
     *
     * _.toNumber(3.2);
     * // => 3.2
     *
     * _.toNumber(Number.MIN_VALUE);
     * // => 5e-324
     *
     * _.toNumber(Infinity);
     * // => Infinity
     *
     * _.toNumber('3.2');
     * // => 3.2
     */
    function toNumber(value) {
      if (typeof value == 'number') {
        return value;
      }
      if (isSymbol(value)) {
        return NAN;
      }
      if (isObject(value)) {
        var other = typeof value.valueOf == 'function' ? value.valueOf() : value;
        value = isObject(other) ? (other + '') : other;
      }
      if (typeof value != 'string') {
        return value === 0 ? value : +value;
      }
      value = value.replace(reTrim, '');
      var isBinary = reIsBinary.test(value);
      return (isBinary || reIsOctal.test(value))
        ? freeParseInt(value.slice(2), isBinary ? 2 : 8)
        : (reIsBadHex.test(value) ? NAN : +value);
    }

    /**
     * Converts `value` to a plain object flattening inherited enumerable string
     * keyed properties of `value` to own properties of the plain object.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Lang
     * @param {*} value The value to convert.
     * @returns {Object} Returns the converted plain object.
     * @example
     *
     * function Foo() {
     *   this.b = 2;
     * }
     *
     * Foo.prototype.c = 3;
     *
     * _.assign({ 'a': 1 }, new Foo);
     * // => { 'a': 1, 'b': 2 }
     *
     * _.assign({ 'a': 1 }, _.toPlainObject(new Foo));
     * // => { 'a': 1, 'b': 2, 'c': 3 }
     */
    function toPlainObject(value) {
      return copyObject(value, keysIn(value));
    }

    /**
     * Converts `value` to a safe integer. A safe integer can be compared and
     * represented correctly.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Lang
     * @param {*} value The value to convert.
     * @returns {number} Returns the converted integer.
     * @example
     *
     * _.toSafeInteger(3.2);
     * // => 3
     *
     * _.toSafeInteger(Number.MIN_VALUE);
     * // => 0
     *
     * _.toSafeInteger(Infinity);
     * // => 9007199254740991
     *
     * _.toSafeInteger('3.2');
     * // => 3
     */
    function toSafeInteger(value) {
      return value
        ? baseClamp(toInteger(value), -MAX_SAFE_INTEGER, MAX_SAFE_INTEGER)
        : (value === 0 ? value : 0);
    }

    /**
     * Converts `value` to a string. An empty string is returned for `null`
     * and `undefined` values. The sign of `-0` is preserved.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Lang
     * @param {*} value The value to convert.
     * @returns {string} Returns the converted string.
     * @example
     *
     * _.toString(null);
     * // => ''
     *
     * _.toString(-0);
     * // => '-0'
     *
     * _.toString([1, 2, 3]);
     * // => '1,2,3'
     */
    function toString(value) {
      return value == null ? '' : baseToString(value);
    }

    /*------------------------------------------------------------------------*/

    /**
     * Assigns own enumerable string keyed properties of source objects to the
     * destination object. Source objects are applied from left to right.
     * Subsequent sources overwrite property assignments of previous sources.
     *
     * **Note:** This method mutates `object` and is loosely based on
     * [`Object.assign`](https://mdn.io/Object/assign).
     *
     * @static
     * @memberOf _
     * @since 0.10.0
     * @category Object
     * @param {Object} object The destination object.
     * @param {...Object} [sources] The source objects.
     * @returns {Object} Returns `object`.
     * @see _.assignIn
     * @example
     *
     * function Foo() {
     *   this.a = 1;
     * }
     *
     * function Bar() {
     *   this.c = 3;
     * }
     *
     * Foo.prototype.b = 2;
     * Bar.prototype.d = 4;
     *
     * _.assign({ 'a': 0 }, new Foo, new Bar);
     * // => { 'a': 1, 'c': 3 }
     */
    var assign = createAssigner(function(object, source) {
      if (isPrototype(source) || isArrayLike(source)) {
        copyObject(source, keys(source), object);
        return;
      }
      for (var key in source) {
        if (hasOwnProperty.call(source, key)) {
          assignValue(object, key, source[key]);
        }
      }
    });

    /**
     * This method is like `_.assign` except that it iterates over own and
     * inherited source properties.
     *
     * **Note:** This method mutates `object`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @alias extend
     * @category Object
     * @param {Object} object The destination object.
     * @param {...Object} [sources] The source objects.
     * @returns {Object} Returns `object`.
     * @see _.assign
     * @example
     *
     * function Foo() {
     *   this.a = 1;
     * }
     *
     * function Bar() {
     *   this.c = 3;
     * }
     *
     * Foo.prototype.b = 2;
     * Bar.prototype.d = 4;
     *
     * _.assignIn({ 'a': 0 }, new Foo, new Bar);
     * // => { 'a': 1, 'b': 2, 'c': 3, 'd': 4 }
     */
    var assignIn = createAssigner(function(object, source) {
      copyObject(source, keysIn(source), object);
    });

    /**
     * This method is like `_.assignIn` except that it accepts `customizer`
     * which is invoked to produce the assigned values. If `customizer` returns
     * `undefined`, assignment is handled by the method instead. The `customizer`
     * is invoked with five arguments: (objValue, srcValue, key, object, source).
     *
     * **Note:** This method mutates `object`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @alias extendWith
     * @category Object
     * @param {Object} object The destination object.
     * @param {...Object} sources The source objects.
     * @param {Function} [customizer] The function to customize assigned values.
     * @returns {Object} Returns `object`.
     * @see _.assignWith
     * @example
     *
     * function customizer(objValue, srcValue) {
     *   return _.isUndefined(objValue) ? srcValue : objValue;
     * }
     *
     * var defaults = _.partialRight(_.assignInWith, customizer);
     *
     * defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });
     * // => { 'a': 1, 'b': 2 }
     */
    var assignInWith = createAssigner(function(object, source, srcIndex, customizer) {
      copyObject(source, keysIn(source), object, customizer);
    });

    /**
     * This method is like `_.assign` except that it accepts `customizer`
     * which is invoked to produce the assigned values. If `customizer` returns
     * `undefined`, assignment is handled by the method instead. The `customizer`
     * is invoked with five arguments: (objValue, srcValue, key, object, source).
     *
     * **Note:** This method mutates `object`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Object
     * @param {Object} object The destination object.
     * @param {...Object} sources The source objects.
     * @param {Function} [customizer] The function to customize assigned values.
     * @returns {Object} Returns `object`.
     * @see _.assignInWith
     * @example
     *
     * function customizer(objValue, srcValue) {
     *   return _.isUndefined(objValue) ? srcValue : objValue;
     * }
     *
     * var defaults = _.partialRight(_.assignWith, customizer);
     *
     * defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });
     * // => { 'a': 1, 'b': 2 }
     */
    var assignWith = createAssigner(function(object, source, srcIndex, customizer) {
      copyObject(source, keys(source), object, customizer);
    });

    /**
     * Creates an array of values corresponding to `paths` of `object`.
     *
     * @static
     * @memberOf _
     * @since 1.0.0
     * @category Object
     * @param {Object} object The object to iterate over.
     * @param {...(string|string[])} [paths] The property paths to pick.
     * @returns {Array} Returns the picked values.
     * @example
     *
     * var object = { 'a': [{ 'b': { 'c': 3 } }, 4] };
     *
     * _.at(object, ['a[0].b.c', 'a[1]']);
     * // => [3, 4]
     */
    var at = flatRest(baseAt);

    /**
     * Creates an object that inherits from the `prototype` object. If a
     * `properties` object is given, its own enumerable string keyed properties
     * are assigned to the created object.
     *
     * @static
     * @memberOf _
     * @since 2.3.0
     * @category Object
     * @param {Object} prototype The object to inherit from.
     * @param {Object} [properties] The properties to assign to the object.
     * @returns {Object} Returns the new object.
     * @example
     *
     * function Shape() {
     *   this.x = 0;
     *   this.y = 0;
     * }
     *
     * function Circle() {
     *   Shape.call(this);
     * }
     *
     * Circle.prototype = _.create(Shape.prototype, {
     *   'constructor': Circle
     * });
     *
     * var circle = new Circle;
     * circle instanceof Circle;
     * // => true
     *
     * circle instanceof Shape;
     * // => true
     */
    function create(prototype, properties) {
      var result = baseCreate(prototype);
      return properties == null ? result : baseAssign(result, properties);
    }

    /**
     * Assigns own and inherited enumerable string keyed properties of source
     * objects to the destination object for all destination properties that
     * resolve to `undefined`. Source objects are applied from left to right.
     * Once a property is set, additional values of the same property are ignored.
     *
     * **Note:** This method mutates `object`.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Object
     * @param {Object} object The destination object.
     * @param {...Object} [sources] The source objects.
     * @returns {Object} Returns `object`.
     * @see _.defaultsDeep
     * @example
     *
     * _.defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });
     * // => { 'a': 1, 'b': 2 }
     */
    var defaults = baseRest(function(args) {
      args.push(undefined, customDefaultsAssignIn);
      return apply(assignInWith, undefined, args);
    });

    /**
     * This method is like `_.defaults` except that it recursively assigns
     * default properties.
     *
     * **Note:** This method mutates `object`.
     *
     * @static
     * @memberOf _
     * @since 3.10.0
     * @category Object
     * @param {Object} object The destination object.
     * @param {...Object} [sources] The source objects.
     * @returns {Object} Returns `object`.
     * @see _.defaults
     * @example
     *
     * _.defaultsDeep({ 'a': { 'b': 2 } }, { 'a': { 'b': 1, 'c': 3 } });
     * // => { 'a': { 'b': 2, 'c': 3 } }
     */
    var defaultsDeep = baseRest(function(args) {
      args.push(undefined, customDefaultsMerge);
      return apply(mergeWith, undefined, args);
    });

    /**
     * This method is like `_.find` except that it returns the key of the first
     * element `predicate` returns truthy for instead of the element itself.
     *
     * @static
     * @memberOf _
     * @since 1.1.0
     * @category Object
     * @param {Object} object The object to inspect.
     * @param {Function} [predicate=_.identity] The function invoked per iteration.
     * @returns {string|undefined} Returns the key of the matched element,
     *  else `undefined`.
     * @example
     *
     * var users = {
     *   'barney':  { 'age': 36, 'active': true },
     *   'fred':    { 'age': 40, 'active': false },
     *   'pebbles': { 'age': 1,  'active': true }
     * };
     *
     * _.findKey(users, function(o) { return o.age < 40; });
     * // => 'barney' (iteration order is not guaranteed)
     *
     * // The `_.matches` iteratee shorthand.
     * _.findKey(users, { 'age': 1, 'active': true });
     * // => 'pebbles'
     *
     * // The `_.matchesProperty` iteratee shorthand.
     * _.findKey(users, ['active', false]);
     * // => 'fred'
     *
     * // The `_.property` iteratee shorthand.
     * _.findKey(users, 'active');
     * // => 'barney'
     */
    function findKey(object, predicate) {
      return baseFindKey(object, getIteratee(predicate, 3), baseForOwn);
    }

    /**
     * This method is like `_.findKey` except that it iterates over elements of
     * a collection in the opposite order.
     *
     * @static
     * @memberOf _
     * @since 2.0.0
     * @category Object
     * @param {Object} object The object to inspect.
     * @param {Function} [predicate=_.identity] The function invoked per iteration.
     * @returns {string|undefined} Returns the key of the matched element,
     *  else `undefined`.
     * @example
     *
     * var users = {
     *   'barney':  { 'age': 36, 'active': true },
     *   'fred':    { 'age': 40, 'active': false },
     *   'pebbles': { 'age': 1,  'active': true }
     * };
     *
     * _.findLastKey(users, function(o) { return o.age < 40; });
     * // => returns 'pebbles' assuming `_.findKey` returns 'barney'
     *
     * // The `_.matches` iteratee shorthand.
     * _.findLastKey(users, { 'age': 36, 'active': true });
     * // => 'barney'
     *
     * // The `_.matchesProperty` iteratee shorthand.
     * _.findLastKey(users, ['active', false]);
     * // => 'fred'
     *
     * // The `_.property` iteratee shorthand.
     * _.findLastKey(users, 'active');
     * // => 'pebbles'
     */
    function findLastKey(object, predicate) {
      return baseFindKey(object, getIteratee(predicate, 3), baseForOwnRight);
    }

    /**
     * Iterates over own and inherited enumerable string keyed properties of an
     * object and invokes `iteratee` for each property. The iteratee is invoked
     * with three arguments: (value, key, object). Iteratee functions may exit
     * iteration early by explicitly returning `false`.
     *
     * @static
     * @memberOf _
     * @since 0.3.0
     * @category Object
     * @param {Object} object The object to iterate over.
     * @param {Function} [iteratee=_.identity] The function invoked per iteration.
     * @returns {Object} Returns `object`.
     * @see _.forInRight
     * @example
     *
     * function Foo() {
     *   this.a = 1;
     *   this.b = 2;
     * }
     *
     * Foo.prototype.c = 3;
     *
     * _.forIn(new Foo, function(value, key) {
     *   console.log(key);
     * });
     * // => Logs 'a', 'b', then 'c' (iteration order is not guaranteed).
     */
    function forIn(object, iteratee) {
      return object == null
        ? object
        : baseFor(object, getIteratee(iteratee, 3), keysIn);
    }

    /**
     * This method is like `_.forIn` except that it iterates over properties of
     * `object` in the opposite order.
     *
     * @static
     * @memberOf _
     * @since 2.0.0
     * @category Object
     * @param {Object} object The object to iterate over.
     * @param {Function} [iteratee=_.identity] The function invoked per iteration.
     * @returns {Object} Returns `object`.
     * @see _.forIn
     * @example
     *
     * function Foo() {
     *   this.a = 1;
     *   this.b = 2;
     * }
     *
     * Foo.prototype.c = 3;
     *
     * _.forInRight(new Foo, function(value, key) {
     *   console.log(key);
     * });
     * // => Logs 'c', 'b', then 'a' assuming `_.forIn` logs 'a', 'b', then 'c'.
     */
    function forInRight(object, iteratee) {
      return object == null
        ? object
        : baseForRight(object, getIteratee(iteratee, 3), keysIn);
    }

    /**
     * Iterates over own enumerable string keyed properties of an object and
     * invokes `iteratee` for each property. The iteratee is invoked with three
     * arguments: (value, key, object). Iteratee functions may exit iteration
     * early by explicitly returning `false`.
     *
     * @static
     * @memberOf _
     * @since 0.3.0
     * @category Object
     * @param {Object} object The object to iterate over.
     * @param {Function} [iteratee=_.identity] The function invoked per iteration.
     * @returns {Object} Returns `object`.
     * @see _.forOwnRight
     * @example
     *
     * function Foo() {
     *   this.a = 1;
     *   this.b = 2;
     * }
     *
     * Foo.prototype.c = 3;
     *
     * _.forOwn(new Foo, function(value, key) {
     *   console.log(key);
     * });
     * // => Logs 'a' then 'b' (iteration order is not guaranteed).
     */
    function forOwn(object, iteratee) {
      return object && baseForOwn(object, getIteratee(iteratee, 3));
    }

    /**
     * This method is like `_.forOwn` except that it iterates over properties of
     * `object` in the opposite order.
     *
     * @static
     * @memberOf _
     * @since 2.0.0
     * @category Object
     * @param {Object} object The object to iterate over.
     * @param {Function} [iteratee=_.identity] The function invoked per iteration.
     * @returns {Object} Returns `object`.
     * @see _.forOwn
     * @example
     *
     * function Foo() {
     *   this.a = 1;
     *   this.b = 2;
     * }
     *
     * Foo.prototype.c = 3;
     *
     * _.forOwnRight(new Foo, function(value, key) {
     *   console.log(key);
     * });
     * // => Logs 'b' then 'a' assuming `_.forOwn` logs 'a' then 'b'.
     */
    function forOwnRight(object, iteratee) {
      return object && baseForOwnRight(object, getIteratee(iteratee, 3));
    }

    /**
     * Creates an array of function property names from own enumerable properties
     * of `object`.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Object
     * @param {Object} object The object to inspect.
     * @returns {Array} Returns the function names.
     * @see _.functionsIn
     * @example
     *
     * function Foo() {
     *   this.a = _.constant('a');
     *   this.b = _.constant('b');
     * }
     *
     * Foo.prototype.c = _.constant('c');
     *
     * _.functions(new Foo);
     * // => ['a', 'b']
     */
    function functions(object) {
      return object == null ? [] : baseFunctions(object, keys(object));
    }

    /**
     * Creates an array of function property names from own and inherited
     * enumerable properties of `object`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Object
     * @param {Object} object The object to inspect.
     * @returns {Array} Returns the function names.
     * @see _.functions
     * @example
     *
     * function Foo() {
     *   this.a = _.constant('a');
     *   this.b = _.constant('b');
     * }
     *
     * Foo.prototype.c = _.constant('c');
     *
     * _.functionsIn(new Foo);
     * // => ['a', 'b', 'c']
     */
    function functionsIn(object) {
      return object == null ? [] : baseFunctions(object, keysIn(object));
    }

    /**
     * Gets the value at `path` of `object`. If the resolved value is
     * `undefined`, the `defaultValue` is returned in its place.
     *
     * @static
     * @memberOf _
     * @since 3.7.0
     * @category Object
     * @param {Object} object The object to query.
     * @param {Array|string} path The path of the property to get.
     * @param {*} [defaultValue] The value returned for `undefined` resolved values.
     * @returns {*} Returns the resolved value.
     * @example
     *
     * var object = { 'a': [{ 'b': { 'c': 3 } }] };
     *
     * _.get(object, 'a[0].b.c');
     * // => 3
     *
     * _.get(object, ['a', '0', 'b', 'c']);
     * // => 3
     *
     * _.get(object, 'a.b.c', 'default');
     * // => 'default'
     */
    function get(object, path, defaultValue) {
      var result = object == null ? undefined : baseGet(object, path);
      return result === undefined ? defaultValue : result;
    }

    /**
     * Checks if `path` is a direct property of `object`.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Object
     * @param {Object} object The object to query.
     * @param {Array|string} path The path to check.
     * @returns {boolean} Returns `true` if `path` exists, else `false`.
     * @example
     *
     * var object = { 'a': { 'b': 2 } };
     * var other = _.create({ 'a': _.create({ 'b': 2 }) });
     *
     * _.has(object, 'a');
     * // => true
     *
     * _.has(object, 'a.b');
     * // => true
     *
     * _.has(object, ['a', 'b']);
     * // => true
     *
     * _.has(other, 'a');
     * // => false
     */
    function has(object, path) {
      return object != null && hasPath(object, path, baseHas);
    }

    /**
     * Checks if `path` is a direct or inherited property of `object`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Object
     * @param {Object} object The object to query.
     * @param {Array|string} path The path to check.
     * @returns {boolean} Returns `true` if `path` exists, else `false`.
     * @example
     *
     * var object = _.create({ 'a': _.create({ 'b': 2 }) });
     *
     * _.hasIn(object, 'a');
     * // => true
     *
     * _.hasIn(object, 'a.b');
     * // => true
     *
     * _.hasIn(object, ['a', 'b']);
     * // => true
     *
     * _.hasIn(object, 'b');
     * // => false
     */
    function hasIn(object, path) {
      return object != null && hasPath(object, path, baseHasIn);
    }

    /**
     * Creates an object composed of the inverted keys and values of `object`.
     * If `object` contains duplicate values, subsequent values overwrite
     * property assignments of previous values.
     *
     * @static
     * @memberOf _
     * @since 0.7.0
     * @category Object
     * @param {Object} object The object to invert.
     * @returns {Object} Returns the new inverted object.
     * @example
     *
     * var object = { 'a': 1, 'b': 2, 'c': 1 };
     *
     * _.invert(object);
     * // => { '1': 'c', '2': 'b' }
     */
    var invert = createInverter(function(result, value, key) {
      result[value] = key;
    }, constant(identity));

    /**
     * This method is like `_.invert` except that the inverted object is generated
     * from the results of running each element of `object` thru `iteratee`. The
     * corresponding inverted value of each inverted key is an array of keys
     * responsible for generating the inverted value. The iteratee is invoked
     * with one argument: (value).
     *
     * @static
     * @memberOf _
     * @since 4.1.0
     * @category Object
     * @param {Object} object The object to invert.
     * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
     * @returns {Object} Returns the new inverted object.
     * @example
     *
     * var object = { 'a': 1, 'b': 2, 'c': 1 };
     *
     * _.invertBy(object);
     * // => { '1': ['a', 'c'], '2': ['b'] }
     *
     * _.invertBy(object, function(value) {
     *   return 'group' + value;
     * });
     * // => { 'group1': ['a', 'c'], 'group2': ['b'] }
     */
    var invertBy = createInverter(function(result, value, key) {
      if (hasOwnProperty.call(result, value)) {
        result[value].push(key);
      } else {
        result[value] = [key];
      }
    }, getIteratee);

    /**
     * Invokes the method at `path` of `object`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Object
     * @param {Object} object The object to query.
     * @param {Array|string} path The path of the method to invoke.
     * @param {...*} [args] The arguments to invoke the method with.
     * @returns {*} Returns the result of the invoked method.
     * @example
     *
     * var object = { 'a': [{ 'b': { 'c': [1, 2, 3, 4] } }] };
     *
     * _.invoke(object, 'a[0].b.c.slice', 1, 3);
     * // => [2, 3]
     */
    var invoke = baseRest(baseInvoke);

    /**
     * Creates an array of the own enumerable property names of `object`.
     *
     * **Note:** Non-object values are coerced to objects. See the
     * [ES spec](http://ecma-international.org/ecma-262/7.0/#sec-object.keys)
     * for more details.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Object
     * @param {Object} object The object to query.
     * @returns {Array} Returns the array of property names.
     * @example
     *
     * function Foo() {
     *   this.a = 1;
     *   this.b = 2;
     * }
     *
     * Foo.prototype.c = 3;
     *
     * _.keys(new Foo);
     * // => ['a', 'b'] (iteration order is not guaranteed)
     *
     * _.keys('hi');
     * // => ['0', '1']
     */
    function keys(object) {
      return isArrayLike(object) ? arrayLikeKeys(object) : baseKeys(object);
    }

    /**
     * Creates an array of the own and inherited enumerable property names of `object`.
     *
     * **Note:** Non-object values are coerced to objects.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Object
     * @param {Object} object The object to query.
     * @returns {Array} Returns the array of property names.
     * @example
     *
     * function Foo() {
     *   this.a = 1;
     *   this.b = 2;
     * }
     *
     * Foo.prototype.c = 3;
     *
     * _.keysIn(new Foo);
     * // => ['a', 'b', 'c'] (iteration order is not guaranteed)
     */
    function keysIn(object) {
      return isArrayLike(object) ? arrayLikeKeys(object, true) : baseKeysIn(object);
    }

    /**
     * The opposite of `_.mapValues`; this method creates an object with the
     * same values as `object` and keys generated by running each own enumerable
     * string keyed property of `object` thru `iteratee`. The iteratee is invoked
     * with three arguments: (value, key, object).
     *
     * @static
     * @memberOf _
     * @since 3.8.0
     * @category Object
     * @param {Object} object The object to iterate over.
     * @param {Function} [iteratee=_.identity] The function invoked per iteration.
     * @returns {Object} Returns the new mapped object.
     * @see _.mapValues
     * @example
     *
     * _.mapKeys({ 'a': 1, 'b': 2 }, function(value, key) {
     *   return key + value;
     * });
     * // => { 'a1': 1, 'b2': 2 }
     */
    function mapKeys(object, iteratee) {
      var result = {};
      iteratee = getIteratee(iteratee, 3);

      baseForOwn(object, function(value, key, object) {
        baseAssignValue(result, iteratee(value, key, object), value);
      });
      return result;
    }

    /**
     * Creates an object with the same keys as `object` and values generated
     * by running each own enumerable string keyed property of `object` thru
     * `iteratee`. The iteratee is invoked with three arguments:
     * (value, key, object).
     *
     * @static
     * @memberOf _
     * @since 2.4.0
     * @category Object
     * @param {Object} object The object to iterate over.
     * @param {Function} [iteratee=_.identity] The function invoked per iteration.
     * @returns {Object} Returns the new mapped object.
     * @see _.mapKeys
     * @example
     *
     * var users = {
     *   'fred':    { 'user': 'fred',    'age': 40 },
     *   'pebbles': { 'user': 'pebbles', 'age': 1 }
     * };
     *
     * _.mapValues(users, function(o) { return o.age; });
     * // => { 'fred': 40, 'pebbles': 1 } (iteration order is not guaranteed)
     *
     * // The `_.property` iteratee shorthand.
     * _.mapValues(users, 'age');
     * // => { 'fred': 40, 'pebbles': 1 } (iteration order is not guaranteed)
     */
    function mapValues(object, iteratee) {
      var result = {};
      iteratee = getIteratee(iteratee, 3);

      baseForOwn(object, function(value, key, object) {
        baseAssignValue(result, key, iteratee(value, key, object));
      });
      return result;
    }

    /**
     * This method is like `_.assign` except that it recursively merges own and
     * inherited enumerable string keyed properties of source objects into the
     * destination object. Source properties that resolve to `undefined` are
     * skipped if a destination value exists. Array and plain object properties
     * are merged recursively. Other objects and value types are overridden by
     * assignment. Source objects are applied from left to right. Subsequent
     * sources overwrite property assignments of previous sources.
     *
     * **Note:** This method mutates `object`.
     *
     * @static
     * @memberOf _
     * @since 0.5.0
     * @category Object
     * @param {Object} object The destination object.
     * @param {...Object} [sources] The source objects.
     * @returns {Object} Returns `object`.
     * @example
     *
     * var object = {
     *   'a': [{ 'b': 2 }, { 'd': 4 }]
     * };
     *
     * var other = {
     *   'a': [{ 'c': 3 }, { 'e': 5 }]
     * };
     *
     * _.merge(object, other);
     * // => { 'a': [{ 'b': 2, 'c': 3 }, { 'd': 4, 'e': 5 }] }
     */
    var merge = createAssigner(function(object, source, srcIndex) {
      baseMerge(object, source, srcIndex);
    });

    /**
     * This method is like `_.merge` except that it accepts `customizer` which
     * is invoked to produce the merged values of the destination and source
     * properties. If `customizer` returns `undefined`, merging is handled by the
     * method instead. The `customizer` is invoked with six arguments:
     * (objValue, srcValue, key, object, source, stack).
     *
     * **Note:** This method mutates `object`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Object
     * @param {Object} object The destination object.
     * @param {...Object} sources The source objects.
     * @param {Function} customizer The function to customize assigned values.
     * @returns {Object} Returns `object`.
     * @example
     *
     * function customizer(objValue, srcValue) {
     *   if (_.isArray(objValue)) {
     *     return objValue.concat(srcValue);
     *   }
     * }
     *
     * var object = { 'a': [1], 'b': [2] };
     * var other = { 'a': [3], 'b': [4] };
     *
     * _.mergeWith(object, other, customizer);
     * // => { 'a': [1, 3], 'b': [2, 4] }
     */
    var mergeWith = createAssigner(function(object, source, srcIndex, customizer) {
      baseMerge(object, source, srcIndex, customizer);
    });

    /**
     * The opposite of `_.pick`; this method creates an object composed of the
     * own and inherited enumerable property paths of `object` that are not omitted.
     *
     * **Note:** This method is considerably slower than `_.pick`.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Object
     * @param {Object} object The source object.
     * @param {...(string|string[])} [paths] The property paths to omit.
     * @returns {Object} Returns the new object.
     * @example
     *
     * var object = { 'a': 1, 'b': '2', 'c': 3 };
     *
     * _.omit(object, ['a', 'c']);
     * // => { 'b': '2' }
     */
    var omit = flatRest(function(object, paths) {
      var result = {};
      if (object == null) {
        return result;
      }
      var isDeep = false;
      paths = arrayMap(paths, function(path) {
        path = castPath(path, object);
        isDeep || (isDeep = path.length > 1);
        return path;
      });
      copyObject(object, getAllKeysIn(object), result);
      if (isDeep) {
        result = baseClone(result, CLONE_DEEP_FLAG | CLONE_FLAT_FLAG | CLONE_SYMBOLS_FLAG, customOmitClone);
      }
      var length = paths.length;
      while (length--) {
        baseUnset(result, paths[length]);
      }
      return result;
    });

    /**
     * The opposite of `_.pickBy`; this method creates an object composed of
     * the own and inherited enumerable string keyed properties of `object` that
     * `predicate` doesn't return truthy for. The predicate is invoked with two
     * arguments: (value, key).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Object
     * @param {Object} object The source object.
     * @param {Function} [predicate=_.identity] The function invoked per property.
     * @returns {Object} Returns the new object.
     * @example
     *
     * var object = { 'a': 1, 'b': '2', 'c': 3 };
     *
     * _.omitBy(object, _.isNumber);
     * // => { 'b': '2' }
     */
    function omitBy(object, predicate) {
      return pickBy(object, negate(getIteratee(predicate)));
    }

    /**
     * Creates an object composed of the picked `object` properties.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Object
     * @param {Object} object The source object.
     * @param {...(string|string[])} [paths] The property paths to pick.
     * @returns {Object} Returns the new object.
     * @example
     *
     * var object = { 'a': 1, 'b': '2', 'c': 3 };
     *
     * _.pick(object, ['a', 'c']);
     * // => { 'a': 1, 'c': 3 }
     */
    var pick = flatRest(function(object, paths) {
      return object == null ? {} : basePick(object, paths);
    });

    /**
     * Creates an object composed of the `object` properties `predicate` returns
     * truthy for. The predicate is invoked with two arguments: (value, key).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Object
     * @param {Object} object The source object.
     * @param {Function} [predicate=_.identity] The function invoked per property.
     * @returns {Object} Returns the new object.
     * @example
     *
     * var object = { 'a': 1, 'b': '2', 'c': 3 };
     *
     * _.pickBy(object, _.isNumber);
     * // => { 'a': 1, 'c': 3 }
     */
    function pickBy(object, predicate) {
      if (object == null) {
        return {};
      }
      var props = arrayMap(getAllKeysIn(object), function(prop) {
        return [prop];
      });
      predicate = getIteratee(predicate);
      return basePickBy(object, props, function(value, path) {
        return predicate(value, path[0]);
      });
    }

    /**
     * This method is like `_.get` except that if the resolved value is a
     * function it's invoked with the `this` binding of its parent object and
     * its result is returned.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Object
     * @param {Object} object The object to query.
     * @param {Array|string} path The path of the property to resolve.
     * @param {*} [defaultValue] The value returned for `undefined` resolved values.
     * @returns {*} Returns the resolved value.
     * @example
     *
     * var object = { 'a': [{ 'b': { 'c1': 3, 'c2': _.constant(4) } }] };
     *
     * _.result(object, 'a[0].b.c1');
     * // => 3
     *
     * _.result(object, 'a[0].b.c2');
     * // => 4
     *
     * _.result(object, 'a[0].b.c3', 'default');
     * // => 'default'
     *
     * _.result(object, 'a[0].b.c3', _.constant('default'));
     * // => 'default'
     */
    function result(object, path, defaultValue) {
      path = castPath(path, object);

      var index = -1,
          length = path.length;

      // Ensure the loop is entered when path is empty.
      if (!length) {
        length = 1;
        object = undefined;
      }
      while (++index < length) {
        var value = object == null ? undefined : object[toKey(path[index])];
        if (value === undefined) {
          index = length;
          value = defaultValue;
        }
        object = isFunction(value) ? value.call(object) : value;
      }
      return object;
    }

    /**
     * Sets the value at `path` of `object`. If a portion of `path` doesn't exist,
     * it's created. Arrays are created for missing index properties while objects
     * are created for all other missing properties. Use `_.setWith` to customize
     * `path` creation.
     *
     * **Note:** This method mutates `object`.
     *
     * @static
     * @memberOf _
     * @since 3.7.0
     * @category Object
     * @param {Object} object The object to modify.
     * @param {Array|string} path The path of the property to set.
     * @param {*} value The value to set.
     * @returns {Object} Returns `object`.
     * @example
     *
     * var object = { 'a': [{ 'b': { 'c': 3 } }] };
     *
     * _.set(object, 'a[0].b.c', 4);
     * console.log(object.a[0].b.c);
     * // => 4
     *
     * _.set(object, ['x', '0', 'y', 'z'], 5);
     * console.log(object.x[0].y.z);
     * // => 5
     */
    function set(object, path, value) {
      return object == null ? object : baseSet(object, path, value);
    }

    /**
     * This method is like `_.set` except that it accepts `customizer` which is
     * invoked to produce the objects of `path`.  If `customizer` returns `undefined`
     * path creation is handled by the method instead. The `customizer` is invoked
     * with three arguments: (nsValue, key, nsObject).
     *
     * **Note:** This method mutates `object`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Object
     * @param {Object} object The object to modify.
     * @param {Array|string} path The path of the property to set.
     * @param {*} value The value to set.
     * @param {Function} [customizer] The function to customize assigned values.
     * @returns {Object} Returns `object`.
     * @example
     *
     * var object = {};
     *
     * _.setWith(object, '[0][1]', 'a', Object);
     * // => { '0': { '1': 'a' } }
     */
    function setWith(object, path, value, customizer) {
      customizer = typeof customizer == 'function' ? customizer : undefined;
      return object == null ? object : baseSet(object, path, value, customizer);
    }

    /**
     * Creates an array of own enumerable string keyed-value pairs for `object`
     * which can be consumed by `_.fromPairs`. If `object` is a map or set, its
     * entries are returned.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @alias entries
     * @category Object
     * @param {Object} object The object to query.
     * @returns {Array} Returns the key-value pairs.
     * @example
     *
     * function Foo() {
     *   this.a = 1;
     *   this.b = 2;
     * }
     *
     * Foo.prototype.c = 3;
     *
     * _.toPairs(new Foo);
     * // => [['a', 1], ['b', 2]] (iteration order is not guaranteed)
     */
    var toPairs = createToPairs(keys);

    /**
     * Creates an array of own and inherited enumerable string keyed-value pairs
     * for `object` which can be consumed by `_.fromPairs`. If `object` is a map
     * or set, its entries are returned.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @alias entriesIn
     * @category Object
     * @param {Object} object The object to query.
     * @returns {Array} Returns the key-value pairs.
     * @example
     *
     * function Foo() {
     *   this.a = 1;
     *   this.b = 2;
     * }
     *
     * Foo.prototype.c = 3;
     *
     * _.toPairsIn(new Foo);
     * // => [['a', 1], ['b', 2], ['c', 3]] (iteration order is not guaranteed)
     */
    var toPairsIn = createToPairs(keysIn);

    /**
     * An alternative to `_.reduce`; this method transforms `object` to a new
     * `accumulator` object which is the result of running each of its own
     * enumerable string keyed properties thru `iteratee`, with each invocation
     * potentially mutating the `accumulator` object. If `accumulator` is not
     * provided, a new object with the same `[[Prototype]]` will be used. The
     * iteratee is invoked with four arguments: (accumulator, value, key, object).
     * Iteratee functions may exit iteration early by explicitly returning `false`.
     *
     * @static
     * @memberOf _
     * @since 1.3.0
     * @category Object
     * @param {Object} object The object to iterate over.
     * @param {Function} [iteratee=_.identity] The function invoked per iteration.
     * @param {*} [accumulator] The custom accumulator value.
     * @returns {*} Returns the accumulated value.
     * @example
     *
     * _.transform([2, 3, 4], function(result, n) {
     *   result.push(n *= n);
     *   return n % 2 == 0;
     * }, []);
     * // => [4, 9]
     *
     * _.transform({ 'a': 1, 'b': 2, 'c': 1 }, function(result, value, key) {
     *   (result[value] || (result[value] = [])).push(key);
     * }, {});
     * // => { '1': ['a', 'c'], '2': ['b'] }
     */
    function transform(object, iteratee, accumulator) {
      var isArr = isArray(object),
          isArrLike = isArr || isBuffer(object) || isTypedArray(object);

      iteratee = getIteratee(iteratee, 4);
      if (accumulator == null) {
        var Ctor = object && object.constructor;
        if (isArrLike) {
          accumulator = isArr ? new Ctor : [];
        }
        else if (isObject(object)) {
          accumulator = isFunction(Ctor) ? baseCreate(getPrototype(object)) : {};
        }
        else {
          accumulator = {};
        }
      }
      (isArrLike ? arrayEach : baseForOwn)(object, function(value, index, object) {
        return iteratee(accumulator, value, index, object);
      });
      return accumulator;
    }

    /**
     * Removes the property at `path` of `object`.
     *
     * **Note:** This method mutates `object`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Object
     * @param {Object} object The object to modify.
     * @param {Array|string} path The path of the property to unset.
     * @returns {boolean} Returns `true` if the property is deleted, else `false`.
     * @example
     *
     * var object = { 'a': [{ 'b': { 'c': 7 } }] };
     * _.unset(object, 'a[0].b.c');
     * // => true
     *
     * console.log(object);
     * // => { 'a': [{ 'b': {} }] };
     *
     * _.unset(object, ['a', '0', 'b', 'c']);
     * // => true
     *
     * console.log(object);
     * // => { 'a': [{ 'b': {} }] };
     */
    function unset(object, path) {
      return object == null ? true : baseUnset(object, path);
    }

    /**
     * This method is like `_.set` except that accepts `updater` to produce the
     * value to set. Use `_.updateWith` to customize `path` creation. The `updater`
     * is invoked with one argument: (value).
     *
     * **Note:** This method mutates `object`.
     *
     * @static
     * @memberOf _
     * @since 4.6.0
     * @category Object
     * @param {Object} object The object to modify.
     * @param {Array|string} path The path of the property to set.
     * @param {Function} updater The function to produce the updated value.
     * @returns {Object} Returns `object`.
     * @example
     *
     * var object = { 'a': [{ 'b': { 'c': 3 } }] };
     *
     * _.update(object, 'a[0].b.c', function(n) { return n * n; });
     * console.log(object.a[0].b.c);
     * // => 9
     *
     * _.update(object, 'x[0].y.z', function(n) { return n ? n + 1 : 0; });
     * console.log(object.x[0].y.z);
     * // => 0
     */
    function update(object, path, updater) {
      return object == null ? object : baseUpdate(object, path, castFunction(updater));
    }

    /**
     * This method is like `_.update` except that it accepts `customizer` which is
     * invoked to produce the objects of `path`.  If `customizer` returns `undefined`
     * path creation is handled by the method instead. The `customizer` is invoked
     * with three arguments: (nsValue, key, nsObject).
     *
     * **Note:** This method mutates `object`.
     *
     * @static
     * @memberOf _
     * @since 4.6.0
     * @category Object
     * @param {Object} object The object to modify.
     * @param {Array|string} path The path of the property to set.
     * @param {Function} updater The function to produce the updated value.
     * @param {Function} [customizer] The function to customize assigned values.
     * @returns {Object} Returns `object`.
     * @example
     *
     * var object = {};
     *
     * _.updateWith(object, '[0][1]', _.constant('a'), Object);
     * // => { '0': { '1': 'a' } }
     */
    function updateWith(object, path, updater, customizer) {
      customizer = typeof customizer == 'function' ? customizer : undefined;
      return object == null ? object : baseUpdate(object, path, castFunction(updater), customizer);
    }

    /**
     * Creates an array of the own enumerable string keyed property values of `object`.
     *
     * **Note:** Non-object values are coerced to objects.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Object
     * @param {Object} object The object to query.
     * @returns {Array} Returns the array of property values.
     * @example
     *
     * function Foo() {
     *   this.a = 1;
     *   this.b = 2;
     * }
     *
     * Foo.prototype.c = 3;
     *
     * _.values(new Foo);
     * // => [1, 2] (iteration order is not guaranteed)
     *
     * _.values('hi');
     * // => ['h', 'i']
     */
    function values(object) {
      return object == null ? [] : baseValues(object, keys(object));
    }

    /**
     * Creates an array of the own and inherited enumerable string keyed property
     * values of `object`.
     *
     * **Note:** Non-object values are coerced to objects.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Object
     * @param {Object} object The object to query.
     * @returns {Array} Returns the array of property values.
     * @example
     *
     * function Foo() {
     *   this.a = 1;
     *   this.b = 2;
     * }
     *
     * Foo.prototype.c = 3;
     *
     * _.valuesIn(new Foo);
     * // => [1, 2, 3] (iteration order is not guaranteed)
     */
    function valuesIn(object) {
      return object == null ? [] : baseValues(object, keysIn(object));
    }

    /*------------------------------------------------------------------------*/

    /**
     * Clamps `number` within the inclusive `lower` and `upper` bounds.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Number
     * @param {number} number The number to clamp.
     * @param {number} [lower] The lower bound.
     * @param {number} upper The upper bound.
     * @returns {number} Returns the clamped number.
     * @example
     *
     * _.clamp(-10, -5, 5);
     * // => -5
     *
     * _.clamp(10, -5, 5);
     * // => 5
     */
    function clamp(number, lower, upper) {
      if (upper === undefined) {
        upper = lower;
        lower = undefined;
      }
      if (upper !== undefined) {
        upper = toNumber(upper);
        upper = upper === upper ? upper : 0;
      }
      if (lower !== undefined) {
        lower = toNumber(lower);
        lower = lower === lower ? lower : 0;
      }
      return baseClamp(toNumber(number), lower, upper);
    }

    /**
     * Checks if `n` is between `start` and up to, but not including, `end`. If
     * `end` is not specified, it's set to `start` with `start` then set to `0`.
     * If `start` is greater than `end` the params are swapped to support
     * negative ranges.
     *
     * @static
     * @memberOf _
     * @since 3.3.0
     * @category Number
     * @param {number} number The number to check.
     * @param {number} [start=0] The start of the range.
     * @param {number} end The end of the range.
     * @returns {boolean} Returns `true` if `number` is in the range, else `false`.
     * @see _.range, _.rangeRight
     * @example
     *
     * _.inRange(3, 2, 4);
     * // => true
     *
     * _.inRange(4, 8);
     * // => true
     *
     * _.inRange(4, 2);
     * // => false
     *
     * _.inRange(2, 2);
     * // => false
     *
     * _.inRange(1.2, 2);
     * // => true
     *
     * _.inRange(5.2, 4);
     * // => false
     *
     * _.inRange(-3, -2, -6);
     * // => true
     */
    function inRange(number, start, end) {
      start = toFinite(start);
      if (end === undefined) {
        end = start;
        start = 0;
      } else {
        end = toFinite(end);
      }
      number = toNumber(number);
      return baseInRange(number, start, end);
    }

    /**
     * Produces a random number between the inclusive `lower` and `upper` bounds.
     * If only one argument is provided a number between `0` and the given number
     * is returned. If `floating` is `true`, or either `lower` or `upper` are
     * floats, a floating-point number is returned instead of an integer.
     *
     * **Note:** JavaScript follows the IEEE-754 standard for resolving
     * floating-point values which can produce unexpected results.
     *
     * @static
     * @memberOf _
     * @since 0.7.0
     * @category Number
     * @param {number} [lower=0] The lower bound.
     * @param {number} [upper=1] The upper bound.
     * @param {boolean} [floating] Specify returning a floating-point number.
     * @returns {number} Returns the random number.
     * @example
     *
     * _.random(0, 5);
     * // => an integer between 0 and 5
     *
     * _.random(5);
     * // => also an integer between 0 and 5
     *
     * _.random(5, true);
     * // => a floating-point number between 0 and 5
     *
     * _.random(1.2, 5.2);
     * // => a floating-point number between 1.2 and 5.2
     */
    function random(lower, upper, floating) {
      if (floating && typeof floating != 'boolean' && isIterateeCall(lower, upper, floating)) {
        upper = floating = undefined;
      }
      if (floating === undefined) {
        if (typeof upper == 'boolean') {
          floating = upper;
          upper = undefined;
        }
        else if (typeof lower == 'boolean') {
          floating = lower;
          lower = undefined;
        }
      }
      if (lower === undefined && upper === undefined) {
        lower = 0;
        upper = 1;
      }
      else {
        lower = toFinite(lower);
        if (upper === undefined) {
          upper = lower;
          lower = 0;
        } else {
          upper = toFinite(upper);
        }
      }
      if (lower > upper) {
        var temp = lower;
        lower = upper;
        upper = temp;
      }
      if (floating || lower % 1 || upper % 1) {
        var rand = nativeRandom();
        return nativeMin(lower + (rand * (upper - lower + freeParseFloat('1e-' + ((rand + '').length - 1)))), upper);
      }
      return baseRandom(lower, upper);
    }

    /*------------------------------------------------------------------------*/

    /**
     * Converts `string` to [camel case](https://en.wikipedia.org/wiki/CamelCase).
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category String
     * @param {string} [string=''] The string to convert.
     * @returns {string} Returns the camel cased string.
     * @example
     *
     * _.camelCase('Foo Bar');
     * // => 'fooBar'
     *
     * _.camelCase('--foo-bar--');
     * // => 'fooBar'
     *
     * _.camelCase('__FOO_BAR__');
     * // => 'fooBar'
     */
    var camelCase = createCompounder(function(result, word, index) {
      word = word.toLowerCase();
      return result + (index ? capitalize(word) : word);
    });

    /**
     * Converts the first character of `string` to upper case and the remaining
     * to lower case.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category String
     * @param {string} [string=''] The string to capitalize.
     * @returns {string} Returns the capitalized string.
     * @example
     *
     * _.capitalize('FRED');
     * // => 'Fred'
     */
    function capitalize(string) {
      return upperFirst(toString(string).toLowerCase());
    }

    /**
     * Deburrs `string` by converting
     * [Latin-1 Supplement](https://en.wikipedia.org/wiki/Latin-1_Supplement_(Unicode_block)#Character_table)
     * and [Latin Extended-A](https://en.wikipedia.org/wiki/Latin_Extended-A)
     * letters to basic Latin letters and removing
     * [combining diacritical marks](https://en.wikipedia.org/wiki/Combining_Diacritical_Marks).
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category String
     * @param {string} [string=''] The string to deburr.
     * @returns {string} Returns the deburred string.
     * @example
     *
     * _.deburr('déjà vu');
     * // => 'deja vu'
     */
    function deburr(string) {
      string = toString(string);
      return string && string.replace(reLatin, deburrLetter).replace(reComboMark, '');
    }

    /**
     * Checks if `string` ends with the given target string.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category String
     * @param {string} [string=''] The string to inspect.
     * @param {string} [target] The string to search for.
     * @param {number} [position=string.length] The position to search up to.
     * @returns {boolean} Returns `true` if `string` ends with `target`,
     *  else `false`.
     * @example
     *
     * _.endsWith('abc', 'c');
     * // => true
     *
     * _.endsWith('abc', 'b');
     * // => false
     *
     * _.endsWith('abc', 'b', 2);
     * // => true
     */
    function endsWith(string, target, position) {
      string = toString(string);
      target = baseToString(target);

      var length = string.length;
      position = position === undefined
        ? length
        : baseClamp(toInteger(position), 0, length);

      var end = position;
      position -= target.length;
      return position >= 0 && string.slice(position, end) == target;
    }

    /**
     * Converts the characters "&", "<", ">", '"', and "'" in `string` to their
     * corresponding HTML entities.
     *
     * **Note:** No other characters are escaped. To escape additional
     * characters use a third-party library like [_he_](https://mths.be/he).
     *
     * Though the ">" character is escaped for symmetry, characters like
     * ">" and "/" don't need escaping in HTML and have no special meaning
     * unless they're part of a tag or unquoted attribute value. See
     * [Mathias Bynens's article](https://mathiasbynens.be/notes/ambiguous-ampersands)
     * (under "semi-related fun fact") for more details.
     *
     * When working with HTML you should always
     * [quote attribute values](http://wonko.com/post/html-escaping) to reduce
     * XSS vectors.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category String
     * @param {string} [string=''] The string to escape.
     * @returns {string} Returns the escaped string.
     * @example
     *
     * _.escape('fred, barney, & pebbles');
     * // => 'fred, barney, &amp; pebbles'
     */
    function escape(string) {
      string = toString(string);
      return (string && reHasUnescapedHtml.test(string))
        ? string.replace(reUnescapedHtml, escapeHtmlChar)
        : string;
    }

    /**
     * Escapes the `RegExp` special characters "^", "$", "\", ".", "*", "+",
     * "?", "(", ")", "[", "]", "{", "}", and "|" in `string`.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category String
     * @param {string} [string=''] The string to escape.
     * @returns {string} Returns the escaped string.
     * @example
     *
     * _.escapeRegExp('[lodash](https://lodash.com/)');
     * // => '\[lodash\]\(https://lodash\.com/\)'
     */
    function escapeRegExp(string) {
      string = toString(string);
      return (string && reHasRegExpChar.test(string))
        ? string.replace(reRegExpChar, '\\$&')
        : string;
    }

    /**
     * Converts `string` to
     * [kebab case](https://en.wikipedia.org/wiki/Letter_case#Special_case_styles).
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category String
     * @param {string} [string=''] The string to convert.
     * @returns {string} Returns the kebab cased string.
     * @example
     *
     * _.kebabCase('Foo Bar');
     * // => 'foo-bar'
     *
     * _.kebabCase('fooBar');
     * // => 'foo-bar'
     *
     * _.kebabCase('__FOO_BAR__');
     * // => 'foo-bar'
     */
    var kebabCase = createCompounder(function(result, word, index) {
      return result + (index ? '-' : '') + word.toLowerCase();
    });

    /**
     * Converts `string`, as space separated words, to lower case.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category String
     * @param {string} [string=''] The string to convert.
     * @returns {string} Returns the lower cased string.
     * @example
     *
     * _.lowerCase('--Foo-Bar--');
     * // => 'foo bar'
     *
     * _.lowerCase('fooBar');
     * // => 'foo bar'
     *
     * _.lowerCase('__FOO_BAR__');
     * // => 'foo bar'
     */
    var lowerCase = createCompounder(function(result, word, index) {
      return result + (index ? ' ' : '') + word.toLowerCase();
    });

    /**
     * Converts the first character of `string` to lower case.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category String
     * @param {string} [string=''] The string to convert.
     * @returns {string} Returns the converted string.
     * @example
     *
     * _.lowerFirst('Fred');
     * // => 'fred'
     *
     * _.lowerFirst('FRED');
     * // => 'fRED'
     */
    var lowerFirst = createCaseFirst('toLowerCase');

    /**
     * Pads `string` on the left and right sides if it's shorter than `length`.
     * Padding characters are truncated if they can't be evenly divided by `length`.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category String
     * @param {string} [string=''] The string to pad.
     * @param {number} [length=0] The padding length.
     * @param {string} [chars=' '] The string used as padding.
     * @returns {string} Returns the padded string.
     * @example
     *
     * _.pad('abc', 8);
     * // => '  abc   '
     *
     * _.pad('abc', 8, '_-');
     * // => '_-abc_-_'
     *
     * _.pad('abc', 3);
     * // => 'abc'
     */
    function pad(string, length, chars) {
      string = toString(string);
      length = toInteger(length);

      var strLength = length ? stringSize(string) : 0;
      if (!length || strLength >= length) {
        return string;
      }
      var mid = (length - strLength) / 2;
      return (
        createPadding(nativeFloor(mid), chars) +
        string +
        createPadding(nativeCeil(mid), chars)
      );
    }

    /**
     * Pads `string` on the right side if it's shorter than `length`. Padding
     * characters are truncated if they exceed `length`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category String
     * @param {string} [string=''] The string to pad.
     * @param {number} [length=0] The padding length.
     * @param {string} [chars=' '] The string used as padding.
     * @returns {string} Returns the padded string.
     * @example
     *
     * _.padEnd('abc', 6);
     * // => 'abc   '
     *
     * _.padEnd('abc', 6, '_-');
     * // => 'abc_-_'
     *
     * _.padEnd('abc', 3);
     * // => 'abc'
     */
    function padEnd(string, length, chars) {
      string = toString(string);
      length = toInteger(length);

      var strLength = length ? stringSize(string) : 0;
      return (length && strLength < length)
        ? (string + createPadding(length - strLength, chars))
        : string;
    }

    /**
     * Pads `string` on the left side if it's shorter than `length`. Padding
     * characters are truncated if they exceed `length`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category String
     * @param {string} [string=''] The string to pad.
     * @param {number} [length=0] The padding length.
     * @param {string} [chars=' '] The string used as padding.
     * @returns {string} Returns the padded string.
     * @example
     *
     * _.padStart('abc', 6);
     * // => '   abc'
     *
     * _.padStart('abc', 6, '_-');
     * // => '_-_abc'
     *
     * _.padStart('abc', 3);
     * // => 'abc'
     */
    function padStart(string, length, chars) {
      string = toString(string);
      length = toInteger(length);

      var strLength = length ? stringSize(string) : 0;
      return (length && strLength < length)
        ? (createPadding(length - strLength, chars) + string)
        : string;
    }

    /**
     * Converts `string` to an integer of the specified radix. If `radix` is
     * `undefined` or `0`, a `radix` of `10` is used unless `value` is a
     * hexadecimal, in which case a `radix` of `16` is used.
     *
     * **Note:** This method aligns with the
     * [ES5 implementation](https://es5.github.io/#x15.1.2.2) of `parseInt`.
     *
     * @static
     * @memberOf _
     * @since 1.1.0
     * @category String
     * @param {string} string The string to convert.
     * @param {number} [radix=10] The radix to interpret `value` by.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
     * @returns {number} Returns the converted integer.
     * @example
     *
     * _.parseInt('08');
     * // => 8
     *
     * _.map(['6', '08', '10'], _.parseInt);
     * // => [6, 8, 10]
     */
    function parseInt(string, radix, guard) {
      if (guard || radix == null) {
        radix = 0;
      } else if (radix) {
        radix = +radix;
      }
      return nativeParseInt(toString(string).replace(reTrimStart, ''), radix || 0);
    }

    /**
     * Repeats the given string `n` times.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category String
     * @param {string} [string=''] The string to repeat.
     * @param {number} [n=1] The number of times to repeat the string.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
     * @returns {string} Returns the repeated string.
     * @example
     *
     * _.repeat('*', 3);
     * // => '***'
     *
     * _.repeat('abc', 2);
     * // => 'abcabc'
     *
     * _.repeat('abc', 0);
     * // => ''
     */
    function repeat(string, n, guard) {
      if ((guard ? isIterateeCall(string, n, guard) : n === undefined)) {
        n = 1;
      } else {
        n = toInteger(n);
      }
      return baseRepeat(toString(string), n);
    }

    /**
     * Replaces matches for `pattern` in `string` with `replacement`.
     *
     * **Note:** This method is based on
     * [`String#replace`](https://mdn.io/String/replace).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category String
     * @param {string} [string=''] The string to modify.
     * @param {RegExp|string} pattern The pattern to replace.
     * @param {Function|string} replacement The match replacement.
     * @returns {string} Returns the modified string.
     * @example
     *
     * _.replace('Hi Fred', 'Fred', 'Barney');
     * // => 'Hi Barney'
     */
    function replace() {
      var args = arguments,
          string = toString(args[0]);

      return args.length < 3 ? string : string.replace(args[1], args[2]);
    }

    /**
     * Converts `string` to
     * [snake case](https://en.wikipedia.org/wiki/Snake_case).
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category String
     * @param {string} [string=''] The string to convert.
     * @returns {string} Returns the snake cased string.
     * @example
     *
     * _.snakeCase('Foo Bar');
     * // => 'foo_bar'
     *
     * _.snakeCase('fooBar');
     * // => 'foo_bar'
     *
     * _.snakeCase('--FOO-BAR--');
     * // => 'foo_bar'
     */
    var snakeCase = createCompounder(function(result, word, index) {
      return result + (index ? '_' : '') + word.toLowerCase();
    });

    /**
     * Splits `string` by `separator`.
     *
     * **Note:** This method is based on
     * [`String#split`](https://mdn.io/String/split).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category String
     * @param {string} [string=''] The string to split.
     * @param {RegExp|string} separator The separator pattern to split by.
     * @param {number} [limit] The length to truncate results to.
     * @returns {Array} Returns the string segments.
     * @example
     *
     * _.split('a-b-c', '-', 2);
     * // => ['a', 'b']
     */
    function split(string, separator, limit) {
      if (limit && typeof limit != 'number' && isIterateeCall(string, separator, limit)) {
        separator = limit = undefined;
      }
      limit = limit === undefined ? MAX_ARRAY_LENGTH : limit >>> 0;
      if (!limit) {
        return [];
      }
      string = toString(string);
      if (string && (
            typeof separator == 'string' ||
            (separator != null && !isRegExp(separator))
          )) {
        separator = baseToString(separator);
        if (!separator && hasUnicode(string)) {
          return castSlice(stringToArray(string), 0, limit);
        }
      }
      return string.split(separator, limit);
    }

    /**
     * Converts `string` to
     * [start case](https://en.wikipedia.org/wiki/Letter_case#Stylistic_or_specialised_usage).
     *
     * @static
     * @memberOf _
     * @since 3.1.0
     * @category String
     * @param {string} [string=''] The string to convert.
     * @returns {string} Returns the start cased string.
     * @example
     *
     * _.startCase('--foo-bar--');
     * // => 'Foo Bar'
     *
     * _.startCase('fooBar');
     * // => 'Foo Bar'
     *
     * _.startCase('__FOO_BAR__');
     * // => 'FOO BAR'
     */
    var startCase = createCompounder(function(result, word, index) {
      return result + (index ? ' ' : '') + upperFirst(word);
    });

    /**
     * Checks if `string` starts with the given target string.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category String
     * @param {string} [string=''] The string to inspect.
     * @param {string} [target] The string to search for.
     * @param {number} [position=0] The position to search from.
     * @returns {boolean} Returns `true` if `string` starts with `target`,
     *  else `false`.
     * @example
     *
     * _.startsWith('abc', 'a');
     * // => true
     *
     * _.startsWith('abc', 'b');
     * // => false
     *
     * _.startsWith('abc', 'b', 1);
     * // => true
     */
    function startsWith(string, target, position) {
      string = toString(string);
      position = position == null
        ? 0
        : baseClamp(toInteger(position), 0, string.length);

      target = baseToString(target);
      return string.slice(position, position + target.length) == target;
    }

    /**
     * Creates a compiled template function that can interpolate data properties
     * in "interpolate" delimiters, HTML-escape interpolated data properties in
     * "escape" delimiters, and execute JavaScript in "evaluate" delimiters. Data
     * properties may be accessed as free variables in the template. If a setting
     * object is given, it takes precedence over `_.templateSettings` values.
     *
     * **Note:** In the development build `_.template` utilizes
     * [sourceURLs](http://www.html5rocks.com/en/tutorials/developertools/sourcemaps/#toc-sourceurl)
     * for easier debugging.
     *
     * For more information on precompiling templates see
     * [lodash's custom builds documentation](https://lodash.com/custom-builds).
     *
     * For more information on Chrome extension sandboxes see
     * [Chrome's extensions documentation](https://developer.chrome.com/extensions/sandboxingEval).
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category String
     * @param {string} [string=''] The template string.
     * @param {Object} [options={}] The options object.
     * @param {RegExp} [options.escape=_.templateSettings.escape]
     *  The HTML "escape" delimiter.
     * @param {RegExp} [options.evaluate=_.templateSettings.evaluate]
     *  The "evaluate" delimiter.
     * @param {Object} [options.imports=_.templateSettings.imports]
     *  An object to import into the template as free variables.
     * @param {RegExp} [options.interpolate=_.templateSettings.interpolate]
     *  The "interpolate" delimiter.
     * @param {string} [options.sourceURL='lodash.templateSources[n]']
     *  The sourceURL of the compiled template.
     * @param {string} [options.variable='obj']
     *  The data object variable name.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
     * @returns {Function} Returns the compiled template function.
     * @example
     *
     * // Use the "interpolate" delimiter to create a compiled template.
     * var compiled = _.template('hello <%= user %>!');
     * compiled({ 'user': 'fred' });
     * // => 'hello fred!'
     *
     * // Use the HTML "escape" delimiter to escape data property values.
     * var compiled = _.template('<b><%- value %></b>');
     * compiled({ 'value': '<script>' });
     * // => '<b>&lt;script&gt;</b>'
     *
     * // Use the "evaluate" delimiter to execute JavaScript and generate HTML.
     * var compiled = _.template('<% _.forEach(users, function(user) { %><li><%- user %></li><% }); %>');
     * compiled({ 'users': ['fred', 'barney'] });
     * // => '<li>fred</li><li>barney</li>'
     *
     * // Use the internal `print` function in "evaluate" delimiters.
     * var compiled = _.template('<% print("hello " + user); %>!');
     * compiled({ 'user': 'barney' });
     * // => 'hello barney!'
     *
     * // Use the ES template literal delimiter as an "interpolate" delimiter.
     * // Disable support by replacing the "interpolate" delimiter.
     * var compiled = _.template('hello ${ user }!');
     * compiled({ 'user': 'pebbles' });
     * // => 'hello pebbles!'
     *
     * // Use backslashes to treat delimiters as plain text.
     * var compiled = _.template('<%= "\\<%- value %\\>" %>');
     * compiled({ 'value': 'ignored' });
     * // => '<%- value %>'
     *
     * // Use the `imports` option to import `jQuery` as `jq`.
     * var text = '<% jq.each(users, function(user) { %><li><%- user %></li><% }); %>';
     * var compiled = _.template(text, { 'imports': { 'jq': jQuery } });
     * compiled({ 'users': ['fred', 'barney'] });
     * // => '<li>fred</li><li>barney</li>'
     *
     * // Use the `sourceURL` option to specify a custom sourceURL for the template.
     * var compiled = _.template('hello <%= user %>!', { 'sourceURL': '/basic/greeting.jst' });
     * compiled(data);
     * // => Find the source of "greeting.jst" under the Sources tab or Resources panel of the web inspector.
     *
     * // Use the `variable` option to ensure a with-statement isn't used in the compiled template.
     * var compiled = _.template('hi <%= data.user %>!', { 'variable': 'data' });
     * compiled.source;
     * // => function(data) {
     * //   var __t, __p = '';
     * //   __p += 'hi ' + ((__t = ( data.user )) == null ? '' : __t) + '!';
     * //   return __p;
     * // }
     *
     * // Use custom template delimiters.
     * _.templateSettings.interpolate = /{{([\s\S]+?)}}/g;
     * var compiled = _.template('hello {{ user }}!');
     * compiled({ 'user': 'mustache' });
     * // => 'hello mustache!'
     *
     * // Use the `source` property to inline compiled templates for meaningful
     * // line numbers in error messages and stack traces.
     * fs.writeFileSync(path.join(process.cwd(), 'jst.js'), '\
     *   var JST = {\
     *     "main": ' + _.template(mainText).source + '\
     *   };\
     * ');
     */
    function template(string, options, guard) {
      // Based on John Resig's `tmpl` implementation
      // (http://ejohn.org/blog/javascript-micro-templating/)
      // and Laura Doktorova's doT.js (https://github.com/olado/doT).
      var settings = lodash.templateSettings;

      if (guard && isIterateeCall(string, options, guard)) {
        options = undefined;
      }
      string = toString(string);
      options = assignInWith({}, options, settings, customDefaultsAssignIn);

      var imports = assignInWith({}, options.imports, settings.imports, customDefaultsAssignIn),
          importsKeys = keys(imports),
          importsValues = baseValues(imports, importsKeys);

      var isEscaping,
          isEvaluating,
          index = 0,
          interpolate = options.interpolate || reNoMatch,
          source = "__p += '";

      // Compile the regexp to match each delimiter.
      var reDelimiters = RegExp(
        (options.escape || reNoMatch).source + '|' +
        interpolate.source + '|' +
        (interpolate === reInterpolate ? reEsTemplate : reNoMatch).source + '|' +
        (options.evaluate || reNoMatch).source + '|$'
      , 'g');

      // Use a sourceURL for easier debugging.
      var sourceURL = '//# sourceURL=' +
        ('sourceURL' in options
          ? options.sourceURL
          : ('lodash.templateSources[' + (++templateCounter) + ']')
        ) + '\n';

      string.replace(reDelimiters, function(match, escapeValue, interpolateValue, esTemplateValue, evaluateValue, offset) {
        interpolateValue || (interpolateValue = esTemplateValue);

        // Escape characters that can't be included in string literals.
        source += string.slice(index, offset).replace(reUnescapedString, escapeStringChar);

        // Replace delimiters with snippets.
        if (escapeValue) {
          isEscaping = true;
          source += "' +\n__e(" + escapeValue + ") +\n'";
        }
        if (evaluateValue) {
          isEvaluating = true;
          source += "';\n" + evaluateValue + ";\n__p += '";
        }
        if (interpolateValue) {
          source += "' +\n((__t = (" + interpolateValue + ")) == null ? '' : __t) +\n'";
        }
        index = offset + match.length;

        // The JS engine embedded in Adobe products needs `match` returned in
        // order to produce the correct `offset` value.
        return match;
      });

      source += "';\n";

      // If `variable` is not specified wrap a with-statement around the generated
      // code to add the data object to the top of the scope chain.
      var variable = options.variable;
      if (!variable) {
        source = 'with (obj) {\n' + source + '\n}\n';
      }
      // Cleanup code by stripping empty strings.
      source = (isEvaluating ? source.replace(reEmptyStringLeading, '') : source)
        .replace(reEmptyStringMiddle, '$1')
        .replace(reEmptyStringTrailing, '$1;');

      // Frame code as the function body.
      source = 'function(' + (variable || 'obj') + ') {\n' +
        (variable
          ? ''
          : 'obj || (obj = {});\n'
        ) +
        "var __t, __p = ''" +
        (isEscaping
           ? ', __e = _.escape'
           : ''
        ) +
        (isEvaluating
          ? ', __j = Array.prototype.join;\n' +
            "function print() { __p += __j.call(arguments, '') }\n"
          : ';\n'
        ) +
        source +
        'return __p\n}';

      var result = attempt(function() {
        return Function(importsKeys, sourceURL + 'return ' + source)
          .apply(undefined, importsValues);
      });

      // Provide the compiled function's source by its `toString` method or
      // the `source` property as a convenience for inlining compiled templates.
      result.source = source;
      if (isError(result)) {
        throw result;
      }
      return result;
    }

    /**
     * Converts `string`, as a whole, to lower case just like
     * [String#toLowerCase](https://mdn.io/toLowerCase).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category String
     * @param {string} [string=''] The string to convert.
     * @returns {string} Returns the lower cased string.
     * @example
     *
     * _.toLower('--Foo-Bar--');
     * // => '--foo-bar--'
     *
     * _.toLower('fooBar');
     * // => 'foobar'
     *
     * _.toLower('__FOO_BAR__');
     * // => '__foo_bar__'
     */
    function toLower(value) {
      return toString(value).toLowerCase();
    }

    /**
     * Converts `string`, as a whole, to upper case just like
     * [String#toUpperCase](https://mdn.io/toUpperCase).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category String
     * @param {string} [string=''] The string to convert.
     * @returns {string} Returns the upper cased string.
     * @example
     *
     * _.toUpper('--foo-bar--');
     * // => '--FOO-BAR--'
     *
     * _.toUpper('fooBar');
     * // => 'FOOBAR'
     *
     * _.toUpper('__foo_bar__');
     * // => '__FOO_BAR__'
     */
    function toUpper(value) {
      return toString(value).toUpperCase();
    }

    /**
     * Removes leading and trailing whitespace or specified characters from `string`.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category String
     * @param {string} [string=''] The string to trim.
     * @param {string} [chars=whitespace] The characters to trim.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
     * @returns {string} Returns the trimmed string.
     * @example
     *
     * _.trim('  abc  ');
     * // => 'abc'
     *
     * _.trim('-_-abc-_-', '_-');
     * // => 'abc'
     *
     * _.map(['  foo  ', '  bar  '], _.trim);
     * // => ['foo', 'bar']
     */
    function trim(string, chars, guard) {
      string = toString(string);
      if (string && (guard || chars === undefined)) {
        return string.replace(reTrim, '');
      }
      if (!string || !(chars = baseToString(chars))) {
        return string;
      }
      var strSymbols = stringToArray(string),
          chrSymbols = stringToArray(chars),
          start = charsStartIndex(strSymbols, chrSymbols),
          end = charsEndIndex(strSymbols, chrSymbols) + 1;

      return castSlice(strSymbols, start, end).join('');
    }

    /**
     * Removes trailing whitespace or specified characters from `string`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category String
     * @param {string} [string=''] The string to trim.
     * @param {string} [chars=whitespace] The characters to trim.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
     * @returns {string} Returns the trimmed string.
     * @example
     *
     * _.trimEnd('  abc  ');
     * // => '  abc'
     *
     * _.trimEnd('-_-abc-_-', '_-');
     * // => '-_-abc'
     */
    function trimEnd(string, chars, guard) {
      string = toString(string);
      if (string && (guard || chars === undefined)) {
        return string.replace(reTrimEnd, '');
      }
      if (!string || !(chars = baseToString(chars))) {
        return string;
      }
      var strSymbols = stringToArray(string),
          end = charsEndIndex(strSymbols, stringToArray(chars)) + 1;

      return castSlice(strSymbols, 0, end).join('');
    }

    /**
     * Removes leading whitespace or specified characters from `string`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category String
     * @param {string} [string=''] The string to trim.
     * @param {string} [chars=whitespace] The characters to trim.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
     * @returns {string} Returns the trimmed string.
     * @example
     *
     * _.trimStart('  abc  ');
     * // => 'abc  '
     *
     * _.trimStart('-_-abc-_-', '_-');
     * // => 'abc-_-'
     */
    function trimStart(string, chars, guard) {
      string = toString(string);
      if (string && (guard || chars === undefined)) {
        return string.replace(reTrimStart, '');
      }
      if (!string || !(chars = baseToString(chars))) {
        return string;
      }
      var strSymbols = stringToArray(string),
          start = charsStartIndex(strSymbols, stringToArray(chars));

      return castSlice(strSymbols, start).join('');
    }

    /**
     * Truncates `string` if it's longer than the given maximum string length.
     * The last characters of the truncated string are replaced with the omission
     * string which defaults to "...".
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category String
     * @param {string} [string=''] The string to truncate.
     * @param {Object} [options={}] The options object.
     * @param {number} [options.length=30] The maximum string length.
     * @param {string} [options.omission='...'] The string to indicate text is omitted.
     * @param {RegExp|string} [options.separator] The separator pattern to truncate to.
     * @returns {string} Returns the truncated string.
     * @example
     *
     * _.truncate('hi-diddly-ho there, neighborino');
     * // => 'hi-diddly-ho there, neighbo...'
     *
     * _.truncate('hi-diddly-ho there, neighborino', {
     *   'length': 24,
     *   'separator': ' '
     * });
     * // => 'hi-diddly-ho there,...'
     *
     * _.truncate('hi-diddly-ho there, neighborino', {
     *   'length': 24,
     *   'separator': /,? +/
     * });
     * // => 'hi-diddly-ho there...'
     *
     * _.truncate('hi-diddly-ho there, neighborino', {
     *   'omission': ' [...]'
     * });
     * // => 'hi-diddly-ho there, neig [...]'
     */
    function truncate(string, options) {
      var length = DEFAULT_TRUNC_LENGTH,
          omission = DEFAULT_TRUNC_OMISSION;

      if (isObject(options)) {
        var separator = 'separator' in options ? options.separator : separator;
        length = 'length' in options ? toInteger(options.length) : length;
        omission = 'omission' in options ? baseToString(options.omission) : omission;
      }
      string = toString(string);

      var strLength = string.length;
      if (hasUnicode(string)) {
        var strSymbols = stringToArray(string);
        strLength = strSymbols.length;
      }
      if (length >= strLength) {
        return string;
      }
      var end = length - stringSize(omission);
      if (end < 1) {
        return omission;
      }
      var result = strSymbols
        ? castSlice(strSymbols, 0, end).join('')
        : string.slice(0, end);

      if (separator === undefined) {
        return result + omission;
      }
      if (strSymbols) {
        end += (result.length - end);
      }
      if (isRegExp(separator)) {
        if (string.slice(end).search(separator)) {
          var match,
              substring = result;

          if (!separator.global) {
            separator = RegExp(separator.source, toString(reFlags.exec(separator)) + 'g');
          }
          separator.lastIndex = 0;
          while ((match = separator.exec(substring))) {
            var newEnd = match.index;
          }
          result = result.slice(0, newEnd === undefined ? end : newEnd);
        }
      } else if (string.indexOf(baseToString(separator), end) != end) {
        var index = result.lastIndexOf(separator);
        if (index > -1) {
          result = result.slice(0, index);
        }
      }
      return result + omission;
    }

    /**
     * The inverse of `_.escape`; this method converts the HTML entities
     * `&amp;`, `&lt;`, `&gt;`, `&quot;`, and `&#39;` in `string` to
     * their corresponding characters.
     *
     * **Note:** No other HTML entities are unescaped. To unescape additional
     * HTML entities use a third-party library like [_he_](https://mths.be/he).
     *
     * @static
     * @memberOf _
     * @since 0.6.0
     * @category String
     * @param {string} [string=''] The string to unescape.
     * @returns {string} Returns the unescaped string.
     * @example
     *
     * _.unescape('fred, barney, &amp; pebbles');
     * // => 'fred, barney, & pebbles'
     */
    function unescape(string) {
      string = toString(string);
      return (string && reHasEscapedHtml.test(string))
        ? string.replace(reEscapedHtml, unescapeHtmlChar)
        : string;
    }

    /**
     * Converts `string`, as space separated words, to upper case.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category String
     * @param {string} [string=''] The string to convert.
     * @returns {string} Returns the upper cased string.
     * @example
     *
     * _.upperCase('--foo-bar');
     * // => 'FOO BAR'
     *
     * _.upperCase('fooBar');
     * // => 'FOO BAR'
     *
     * _.upperCase('__foo_bar__');
     * // => 'FOO BAR'
     */
    var upperCase = createCompounder(function(result, word, index) {
      return result + (index ? ' ' : '') + word.toUpperCase();
    });

    /**
     * Converts the first character of `string` to upper case.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category String
     * @param {string} [string=''] The string to convert.
     * @returns {string} Returns the converted string.
     * @example
     *
     * _.upperFirst('fred');
     * // => 'Fred'
     *
     * _.upperFirst('FRED');
     * // => 'FRED'
     */
    var upperFirst = createCaseFirst('toUpperCase');

    /**
     * Splits `string` into an array of its words.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category String
     * @param {string} [string=''] The string to inspect.
     * @param {RegExp|string} [pattern] The pattern to match words.
     * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
     * @returns {Array} Returns the words of `string`.
     * @example
     *
     * _.words('fred, barney, & pebbles');
     * // => ['fred', 'barney', 'pebbles']
     *
     * _.words('fred, barney, & pebbles', /[^, ]+/g);
     * // => ['fred', 'barney', '&', 'pebbles']
     */
    function words(string, pattern, guard) {
      string = toString(string);
      pattern = guard ? undefined : pattern;

      if (pattern === undefined) {
        return hasUnicodeWord(string) ? unicodeWords(string) : asciiWords(string);
      }
      return string.match(pattern) || [];
    }

    /*------------------------------------------------------------------------*/

    /**
     * Attempts to invoke `func`, returning either the result or the caught error
     * object. Any additional arguments are provided to `func` when it's invoked.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Util
     * @param {Function} func The function to attempt.
     * @param {...*} [args] The arguments to invoke `func` with.
     * @returns {*} Returns the `func` result or error object.
     * @example
     *
     * // Avoid throwing errors for invalid selectors.
     * var elements = _.attempt(function(selector) {
     *   return document.querySelectorAll(selector);
     * }, '>_>');
     *
     * if (_.isError(elements)) {
     *   elements = [];
     * }
     */
    var attempt = baseRest(function(func, args) {
      try {
        return apply(func, undefined, args);
      } catch (e) {
        return isError(e) ? e : new Error(e);
      }
    });

    /**
     * Binds methods of an object to the object itself, overwriting the existing
     * method.
     *
     * **Note:** This method doesn't set the "length" property of bound functions.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Util
     * @param {Object} object The object to bind and assign the bound methods to.
     * @param {...(string|string[])} methodNames The object method names to bind.
     * @returns {Object} Returns `object`.
     * @example
     *
     * var view = {
     *   'label': 'docs',
     *   'click': function() {
     *     console.log('clicked ' + this.label);
     *   }
     * };
     *
     * _.bindAll(view, ['click']);
     * jQuery(element).on('click', view.click);
     * // => Logs 'clicked docs' when clicked.
     */
    var bindAll = flatRest(function(object, methodNames) {
      arrayEach(methodNames, function(key) {
        key = toKey(key);
        baseAssignValue(object, key, bind(object[key], object));
      });
      return object;
    });

    /**
     * Creates a function that iterates over `pairs` and invokes the corresponding
     * function of the first predicate to return truthy. The predicate-function
     * pairs are invoked with the `this` binding and arguments of the created
     * function.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Util
     * @param {Array} pairs The predicate-function pairs.
     * @returns {Function} Returns the new composite function.
     * @example
     *
     * var func = _.cond([
     *   [_.matches({ 'a': 1 }),           _.constant('matches A')],
     *   [_.conforms({ 'b': _.isNumber }), _.constant('matches B')],
     *   [_.stubTrue,                      _.constant('no match')]
     * ]);
     *
     * func({ 'a': 1, 'b': 2 });
     * // => 'matches A'
     *
     * func({ 'a': 0, 'b': 1 });
     * // => 'matches B'
     *
     * func({ 'a': '1', 'b': '2' });
     * // => 'no match'
     */
    function cond(pairs) {
      var length = pairs == null ? 0 : pairs.length,
          toIteratee = getIteratee();

      pairs = !length ? [] : arrayMap(pairs, function(pair) {
        if (typeof pair[1] != 'function') {
          throw new TypeError(FUNC_ERROR_TEXT);
        }
        return [toIteratee(pair[0]), pair[1]];
      });

      return baseRest(function(args) {
        var index = -1;
        while (++index < length) {
          var pair = pairs[index];
          if (apply(pair[0], this, args)) {
            return apply(pair[1], this, args);
          }
        }
      });
    }

    /**
     * Creates a function that invokes the predicate properties of `source` with
     * the corresponding property values of a given object, returning `true` if
     * all predicates return truthy, else `false`.
     *
     * **Note:** The created function is equivalent to `_.conformsTo` with
     * `source` partially applied.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Util
     * @param {Object} source The object of property predicates to conform to.
     * @returns {Function} Returns the new spec function.
     * @example
     *
     * var objects = [
     *   { 'a': 2, 'b': 1 },
     *   { 'a': 1, 'b': 2 }
     * ];
     *
     * _.filter(objects, _.conforms({ 'b': function(n) { return n > 1; } }));
     * // => [{ 'a': 1, 'b': 2 }]
     */
    function conforms(source) {
      return baseConforms(baseClone(source, CLONE_DEEP_FLAG));
    }

    /**
     * Creates a function that returns `value`.
     *
     * @static
     * @memberOf _
     * @since 2.4.0
     * @category Util
     * @param {*} value The value to return from the new function.
     * @returns {Function} Returns the new constant function.
     * @example
     *
     * var objects = _.times(2, _.constant({ 'a': 1 }));
     *
     * console.log(objects);
     * // => [{ 'a': 1 }, { 'a': 1 }]
     *
     * console.log(objects[0] === objects[1]);
     * // => true
     */
    function constant(value) {
      return function() {
        return value;
      };
    }

    /**
     * Checks `value` to determine whether a default value should be returned in
     * its place. The `defaultValue` is returned if `value` is `NaN`, `null`,
     * or `undefined`.
     *
     * @static
     * @memberOf _
     * @since 4.14.0
     * @category Util
     * @param {*} value The value to check.
     * @param {*} defaultValue The default value.
     * @returns {*} Returns the resolved value.
     * @example
     *
     * _.defaultTo(1, 10);
     * // => 1
     *
     * _.defaultTo(undefined, 10);
     * // => 10
     */
    function defaultTo(value, defaultValue) {
      return (value == null || value !== value) ? defaultValue : value;
    }

    /**
     * Creates a function that returns the result of invoking the given functions
     * with the `this` binding of the created function, where each successive
     * invocation is supplied the return value of the previous.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Util
     * @param {...(Function|Function[])} [funcs] The functions to invoke.
     * @returns {Function} Returns the new composite function.
     * @see _.flowRight
     * @example
     *
     * function square(n) {
     *   return n * n;
     * }
     *
     * var addSquare = _.flow([_.add, square]);
     * addSquare(1, 2);
     * // => 9
     */
    var flow = createFlow();

    /**
     * This method is like `_.flow` except that it creates a function that
     * invokes the given functions from right to left.
     *
     * @static
     * @since 3.0.0
     * @memberOf _
     * @category Util
     * @param {...(Function|Function[])} [funcs] The functions to invoke.
     * @returns {Function} Returns the new composite function.
     * @see _.flow
     * @example
     *
     * function square(n) {
     *   return n * n;
     * }
     *
     * var addSquare = _.flowRight([square, _.add]);
     * addSquare(1, 2);
     * // => 9
     */
    var flowRight = createFlow(true);

    /**
     * This method returns the first argument it receives.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Util
     * @param {*} value Any value.
     * @returns {*} Returns `value`.
     * @example
     *
     * var object = { 'a': 1 };
     *
     * console.log(_.identity(object) === object);
     * // => true
     */
    function identity(value) {
      return value;
    }

    /**
     * Creates a function that invokes `func` with the arguments of the created
     * function. If `func` is a property name, the created function returns the
     * property value for a given element. If `func` is an array or object, the
     * created function returns `true` for elements that contain the equivalent
     * source properties, otherwise it returns `false`.
     *
     * @static
     * @since 4.0.0
     * @memberOf _
     * @category Util
     * @param {*} [func=_.identity] The value to convert to a callback.
     * @returns {Function} Returns the callback.
     * @example
     *
     * var users = [
     *   { 'user': 'barney', 'age': 36, 'active': true },
     *   { 'user': 'fred',   'age': 40, 'active': false }
     * ];
     *
     * // The `_.matches` iteratee shorthand.
     * _.filter(users, _.iteratee({ 'user': 'barney', 'active': true }));
     * // => [{ 'user': 'barney', 'age': 36, 'active': true }]
     *
     * // The `_.matchesProperty` iteratee shorthand.
     * _.filter(users, _.iteratee(['user', 'fred']));
     * // => [{ 'user': 'fred', 'age': 40 }]
     *
     * // The `_.property` iteratee shorthand.
     * _.map(users, _.iteratee('user'));
     * // => ['barney', 'fred']
     *
     * // Create custom iteratee shorthands.
     * _.iteratee = _.wrap(_.iteratee, function(iteratee, func) {
     *   return !_.isRegExp(func) ? iteratee(func) : function(string) {
     *     return func.test(string);
     *   };
     * });
     *
     * _.filter(['abc', 'def'], /ef/);
     * // => ['def']
     */
    function iteratee(func) {
      return baseIteratee(typeof func == 'function' ? func : baseClone(func, CLONE_DEEP_FLAG));
    }

    /**
     * Creates a function that performs a partial deep comparison between a given
     * object and `source`, returning `true` if the given object has equivalent
     * property values, else `false`.
     *
     * **Note:** The created function is equivalent to `_.isMatch` with `source`
     * partially applied.
     *
     * Partial comparisons will match empty array and empty object `source`
     * values against any array or object value, respectively. See `_.isEqual`
     * for a list of supported value comparisons.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Util
     * @param {Object} source The object of property values to match.
     * @returns {Function} Returns the new spec function.
     * @example
     *
     * var objects = [
     *   { 'a': 1, 'b': 2, 'c': 3 },
     *   { 'a': 4, 'b': 5, 'c': 6 }
     * ];
     *
     * _.filter(objects, _.matches({ 'a': 4, 'c': 6 }));
     * // => [{ 'a': 4, 'b': 5, 'c': 6 }]
     */
    function matches(source) {
      return baseMatches(baseClone(source, CLONE_DEEP_FLAG));
    }

    /**
     * Creates a function that performs a partial deep comparison between the
     * value at `path` of a given object to `srcValue`, returning `true` if the
     * object value is equivalent, else `false`.
     *
     * **Note:** Partial comparisons will match empty array and empty object
     * `srcValue` values against any array or object value, respectively. See
     * `_.isEqual` for a list of supported value comparisons.
     *
     * @static
     * @memberOf _
     * @since 3.2.0
     * @category Util
     * @param {Array|string} path The path of the property to get.
     * @param {*} srcValue The value to match.
     * @returns {Function} Returns the new spec function.
     * @example
     *
     * var objects = [
     *   { 'a': 1, 'b': 2, 'c': 3 },
     *   { 'a': 4, 'b': 5, 'c': 6 }
     * ];
     *
     * _.find(objects, _.matchesProperty('a', 4));
     * // => { 'a': 4, 'b': 5, 'c': 6 }
     */
    function matchesProperty(path, srcValue) {
      return baseMatchesProperty(path, baseClone(srcValue, CLONE_DEEP_FLAG));
    }

    /**
     * Creates a function that invokes the method at `path` of a given object.
     * Any additional arguments are provided to the invoked method.
     *
     * @static
     * @memberOf _
     * @since 3.7.0
     * @category Util
     * @param {Array|string} path The path of the method to invoke.
     * @param {...*} [args] The arguments to invoke the method with.
     * @returns {Function} Returns the new invoker function.
     * @example
     *
     * var objects = [
     *   { 'a': { 'b': _.constant(2) } },
     *   { 'a': { 'b': _.constant(1) } }
     * ];
     *
     * _.map(objects, _.method('a.b'));
     * // => [2, 1]
     *
     * _.map(objects, _.method(['a', 'b']));
     * // => [2, 1]
     */
    var method = baseRest(function(path, args) {
      return function(object) {
        return baseInvoke(object, path, args);
      };
    });

    /**
     * The opposite of `_.method`; this method creates a function that invokes
     * the method at a given path of `object`. Any additional arguments are
     * provided to the invoked method.
     *
     * @static
     * @memberOf _
     * @since 3.7.0
     * @category Util
     * @param {Object} object The object to query.
     * @param {...*} [args] The arguments to invoke the method with.
     * @returns {Function} Returns the new invoker function.
     * @example
     *
     * var array = _.times(3, _.constant),
     *     object = { 'a': array, 'b': array, 'c': array };
     *
     * _.map(['a[2]', 'c[0]'], _.methodOf(object));
     * // => [2, 0]
     *
     * _.map([['a', '2'], ['c', '0']], _.methodOf(object));
     * // => [2, 0]
     */
    var methodOf = baseRest(function(object, args) {
      return function(path) {
        return baseInvoke(object, path, args);
      };
    });

    /**
     * Adds all own enumerable string keyed function properties of a source
     * object to the destination object. If `object` is a function, then methods
     * are added to its prototype as well.
     *
     * **Note:** Use `_.runInContext` to create a pristine `lodash` function to
     * avoid conflicts caused by modifying the original.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Util
     * @param {Function|Object} [object=lodash] The destination object.
     * @param {Object} source The object of functions to add.
     * @param {Object} [options={}] The options object.
     * @param {boolean} [options.chain=true] Specify whether mixins are chainable.
     * @returns {Function|Object} Returns `object`.
     * @example
     *
     * function vowels(string) {
     *   return _.filter(string, function(v) {
     *     return /[aeiou]/i.test(v);
     *   });
     * }
     *
     * _.mixin({ 'vowels': vowels });
     * _.vowels('fred');
     * // => ['e']
     *
     * _('fred').vowels().value();
     * // => ['e']
     *
     * _.mixin({ 'vowels': vowels }, { 'chain': false });
     * _('fred').vowels();
     * // => ['e']
     */
    function mixin(object, source, options) {
      var props = keys(source),
          methodNames = baseFunctions(source, props);

      if (options == null &&
          !(isObject(source) && (methodNames.length || !props.length))) {
        options = source;
        source = object;
        object = this;
        methodNames = baseFunctions(source, keys(source));
      }
      var chain = !(isObject(options) && 'chain' in options) || !!options.chain,
          isFunc = isFunction(object);

      arrayEach(methodNames, function(methodName) {
        var func = source[methodName];
        object[methodName] = func;
        if (isFunc) {
          object.prototype[methodName] = function() {
            var chainAll = this.__chain__;
            if (chain || chainAll) {
              var result = object(this.__wrapped__),
                  actions = result.__actions__ = copyArray(this.__actions__);

              actions.push({ 'func': func, 'args': arguments, 'thisArg': object });
              result.__chain__ = chainAll;
              return result;
            }
            return func.apply(object, arrayPush([this.value()], arguments));
          };
        }
      });

      return object;
    }

    /**
     * Reverts the `_` variable to its previous value and returns a reference to
     * the `lodash` function.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Util
     * @returns {Function} Returns the `lodash` function.
     * @example
     *
     * var lodash = _.noConflict();
     */
    function noConflict() {
      if (root._ === this) {
        root._ = oldDash;
      }
      return this;
    }

    /**
     * This method returns `undefined`.
     *
     * @static
     * @memberOf _
     * @since 2.3.0
     * @category Util
     * @example
     *
     * _.times(2, _.noop);
     * // => [undefined, undefined]
     */
    function noop() {
      // No operation performed.
    }

    /**
     * Creates a function that gets the argument at index `n`. If `n` is negative,
     * the nth argument from the end is returned.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Util
     * @param {number} [n=0] The index of the argument to return.
     * @returns {Function} Returns the new pass-thru function.
     * @example
     *
     * var func = _.nthArg(1);
     * func('a', 'b', 'c', 'd');
     * // => 'b'
     *
     * var func = _.nthArg(-2);
     * func('a', 'b', 'c', 'd');
     * // => 'c'
     */
    function nthArg(n) {
      n = toInteger(n);
      return baseRest(function(args) {
        return baseNth(args, n);
      });
    }

    /**
     * Creates a function that invokes `iteratees` with the arguments it receives
     * and returns their results.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Util
     * @param {...(Function|Function[])} [iteratees=[_.identity]]
     *  The iteratees to invoke.
     * @returns {Function} Returns the new function.
     * @example
     *
     * var func = _.over([Math.max, Math.min]);
     *
     * func(1, 2, 3, 4);
     * // => [4, 1]
     */
    var over = createOver(arrayMap);

    /**
     * Creates a function that checks if **all** of the `predicates` return
     * truthy when invoked with the arguments it receives.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Util
     * @param {...(Function|Function[])} [predicates=[_.identity]]
     *  The predicates to check.
     * @returns {Function} Returns the new function.
     * @example
     *
     * var func = _.overEvery([Boolean, isFinite]);
     *
     * func('1');
     * // => true
     *
     * func(null);
     * // => false
     *
     * func(NaN);
     * // => false
     */
    var overEvery = createOver(arrayEvery);

    /**
     * Creates a function that checks if **any** of the `predicates` return
     * truthy when invoked with the arguments it receives.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Util
     * @param {...(Function|Function[])} [predicates=[_.identity]]
     *  The predicates to check.
     * @returns {Function} Returns the new function.
     * @example
     *
     * var func = _.overSome([Boolean, isFinite]);
     *
     * func('1');
     * // => true
     *
     * func(null);
     * // => true
     *
     * func(NaN);
     * // => false
     */
    var overSome = createOver(arraySome);

    /**
     * Creates a function that returns the value at `path` of a given object.
     *
     * @static
     * @memberOf _
     * @since 2.4.0
     * @category Util
     * @param {Array|string} path The path of the property to get.
     * @returns {Function} Returns the new accessor function.
     * @example
     *
     * var objects = [
     *   { 'a': { 'b': 2 } },
     *   { 'a': { 'b': 1 } }
     * ];
     *
     * _.map(objects, _.property('a.b'));
     * // => [2, 1]
     *
     * _.map(_.sortBy(objects, _.property(['a', 'b'])), 'a.b');
     * // => [1, 2]
     */
    function property(path) {
      return isKey(path) ? baseProperty(toKey(path)) : basePropertyDeep(path);
    }

    /**
     * The opposite of `_.property`; this method creates a function that returns
     * the value at a given path of `object`.
     *
     * @static
     * @memberOf _
     * @since 3.0.0
     * @category Util
     * @param {Object} object The object to query.
     * @returns {Function} Returns the new accessor function.
     * @example
     *
     * var array = [0, 1, 2],
     *     object = { 'a': array, 'b': array, 'c': array };
     *
     * _.map(['a[2]', 'c[0]'], _.propertyOf(object));
     * // => [2, 0]
     *
     * _.map([['a', '2'], ['c', '0']], _.propertyOf(object));
     * // => [2, 0]
     */
    function propertyOf(object) {
      return function(path) {
        return object == null ? undefined : baseGet(object, path);
      };
    }

    /**
     * Creates an array of numbers (positive and/or negative) progressing from
     * `start` up to, but not including, `end`. A step of `-1` is used if a negative
     * `start` is specified without an `end` or `step`. If `end` is not specified,
     * it's set to `start` with `start` then set to `0`.
     *
     * **Note:** JavaScript follows the IEEE-754 standard for resolving
     * floating-point values which can produce unexpected results.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Util
     * @param {number} [start=0] The start of the range.
     * @param {number} end The end of the range.
     * @param {number} [step=1] The value to increment or decrement by.
     * @returns {Array} Returns the range of numbers.
     * @see _.inRange, _.rangeRight
     * @example
     *
     * _.range(4);
     * // => [0, 1, 2, 3]
     *
     * _.range(-4);
     * // => [0, -1, -2, -3]
     *
     * _.range(1, 5);
     * // => [1, 2, 3, 4]
     *
     * _.range(0, 20, 5);
     * // => [0, 5, 10, 15]
     *
     * _.range(0, -4, -1);
     * // => [0, -1, -2, -3]
     *
     * _.range(1, 4, 0);
     * // => [1, 1, 1]
     *
     * _.range(0);
     * // => []
     */
    var range = createRange();

    /**
     * This method is like `_.range` except that it populates values in
     * descending order.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Util
     * @param {number} [start=0] The start of the range.
     * @param {number} end The end of the range.
     * @param {number} [step=1] The value to increment or decrement by.
     * @returns {Array} Returns the range of numbers.
     * @see _.inRange, _.range
     * @example
     *
     * _.rangeRight(4);
     * // => [3, 2, 1, 0]
     *
     * _.rangeRight(-4);
     * // => [-3, -2, -1, 0]
     *
     * _.rangeRight(1, 5);
     * // => [4, 3, 2, 1]
     *
     * _.rangeRight(0, 20, 5);
     * // => [15, 10, 5, 0]
     *
     * _.rangeRight(0, -4, -1);
     * // => [-3, -2, -1, 0]
     *
     * _.rangeRight(1, 4, 0);
     * // => [1, 1, 1]
     *
     * _.rangeRight(0);
     * // => []
     */
    var rangeRight = createRange(true);

    /**
     * This method returns a new empty array.
     *
     * @static
     * @memberOf _
     * @since 4.13.0
     * @category Util
     * @returns {Array} Returns the new empty array.
     * @example
     *
     * var arrays = _.times(2, _.stubArray);
     *
     * console.log(arrays);
     * // => [[], []]
     *
     * console.log(arrays[0] === arrays[1]);
     * // => false
     */
    function stubArray() {
      return [];
    }

    /**
     * This method returns `false`.
     *
     * @static
     * @memberOf _
     * @since 4.13.0
     * @category Util
     * @returns {boolean} Returns `false`.
     * @example
     *
     * _.times(2, _.stubFalse);
     * // => [false, false]
     */
    function stubFalse() {
      return false;
    }

    /**
     * This method returns a new empty object.
     *
     * @static
     * @memberOf _
     * @since 4.13.0
     * @category Util
     * @returns {Object} Returns the new empty object.
     * @example
     *
     * var objects = _.times(2, _.stubObject);
     *
     * console.log(objects);
     * // => [{}, {}]
     *
     * console.log(objects[0] === objects[1]);
     * // => false
     */
    function stubObject() {
      return {};
    }

    /**
     * This method returns an empty string.
     *
     * @static
     * @memberOf _
     * @since 4.13.0
     * @category Util
     * @returns {string} Returns the empty string.
     * @example
     *
     * _.times(2, _.stubString);
     * // => ['', '']
     */
    function stubString() {
      return '';
    }

    /**
     * This method returns `true`.
     *
     * @static
     * @memberOf _
     * @since 4.13.0
     * @category Util
     * @returns {boolean} Returns `true`.
     * @example
     *
     * _.times(2, _.stubTrue);
     * // => [true, true]
     */
    function stubTrue() {
      return true;
    }

    /**
     * Invokes the iteratee `n` times, returning an array of the results of
     * each invocation. The iteratee is invoked with one argument; (index).
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Util
     * @param {number} n The number of times to invoke `iteratee`.
     * @param {Function} [iteratee=_.identity] The function invoked per iteration.
     * @returns {Array} Returns the array of results.
     * @example
     *
     * _.times(3, String);
     * // => ['0', '1', '2']
     *
     *  _.times(4, _.constant(0));
     * // => [0, 0, 0, 0]
     */
    function times(n, iteratee) {
      n = toInteger(n);
      if (n < 1 || n > MAX_SAFE_INTEGER) {
        return [];
      }
      var index = MAX_ARRAY_LENGTH,
          length = nativeMin(n, MAX_ARRAY_LENGTH);

      iteratee = getIteratee(iteratee);
      n -= MAX_ARRAY_LENGTH;

      var result = baseTimes(length, iteratee);
      while (++index < n) {
        iteratee(index);
      }
      return result;
    }

    /**
     * Converts `value` to a property path array.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Util
     * @param {*} value The value to convert.
     * @returns {Array} Returns the new property path array.
     * @example
     *
     * _.toPath('a.b.c');
     * // => ['a', 'b', 'c']
     *
     * _.toPath('a[0].b.c');
     * // => ['a', '0', 'b', 'c']
     */
    function toPath(value) {
      if (isArray(value)) {
        return arrayMap(value, toKey);
      }
      return isSymbol(value) ? [value] : copyArray(stringToPath(toString(value)));
    }

    /**
     * Generates a unique ID. If `prefix` is given, the ID is appended to it.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Util
     * @param {string} [prefix=''] The value to prefix the ID with.
     * @returns {string} Returns the unique ID.
     * @example
     *
     * _.uniqueId('contact_');
     * // => 'contact_104'
     *
     * _.uniqueId();
     * // => '105'
     */
    function uniqueId(prefix) {
      var id = ++idCounter;
      return toString(prefix) + id;
    }

    /*------------------------------------------------------------------------*/

    /**
     * Adds two numbers.
     *
     * @static
     * @memberOf _
     * @since 3.4.0
     * @category Math
     * @param {number} augend The first number in an addition.
     * @param {number} addend The second number in an addition.
     * @returns {number} Returns the total.
     * @example
     *
     * _.add(6, 4);
     * // => 10
     */
    var add = createMathOperation(function(augend, addend) {
      return augend + addend;
    }, 0);

    /**
     * Computes `number` rounded up to `precision`.
     *
     * @static
     * @memberOf _
     * @since 3.10.0
     * @category Math
     * @param {number} number The number to round up.
     * @param {number} [precision=0] The precision to round up to.
     * @returns {number} Returns the rounded up number.
     * @example
     *
     * _.ceil(4.006);
     * // => 5
     *
     * _.ceil(6.004, 2);
     * // => 6.01
     *
     * _.ceil(6040, -2);
     * // => 6100
     */
    var ceil = createRound('ceil');

    /**
     * Divide two numbers.
     *
     * @static
     * @memberOf _
     * @since 4.7.0
     * @category Math
     * @param {number} dividend The first number in a division.
     * @param {number} divisor The second number in a division.
     * @returns {number} Returns the quotient.
     * @example
     *
     * _.divide(6, 4);
     * // => 1.5
     */
    var divide = createMathOperation(function(dividend, divisor) {
      return dividend / divisor;
    }, 1);

    /**
     * Computes `number` rounded down to `precision`.
     *
     * @static
     * @memberOf _
     * @since 3.10.0
     * @category Math
     * @param {number} number The number to round down.
     * @param {number} [precision=0] The precision to round down to.
     * @returns {number} Returns the rounded down number.
     * @example
     *
     * _.floor(4.006);
     * // => 4
     *
     * _.floor(0.046, 2);
     * // => 0.04
     *
     * _.floor(4060, -2);
     * // => 4000
     */
    var floor = createRound('floor');

    /**
     * Computes the maximum value of `array`. If `array` is empty or falsey,
     * `undefined` is returned.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Math
     * @param {Array} array The array to iterate over.
     * @returns {*} Returns the maximum value.
     * @example
     *
     * _.max([4, 2, 8, 6]);
     * // => 8
     *
     * _.max([]);
     * // => undefined
     */
    function max(array) {
      return (array && array.length)
        ? baseExtremum(array, identity, baseGt)
        : undefined;
    }

    /**
     * This method is like `_.max` except that it accepts `iteratee` which is
     * invoked for each element in `array` to generate the criterion by which
     * the value is ranked. The iteratee is invoked with one argument: (value).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Math
     * @param {Array} array The array to iterate over.
     * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
     * @returns {*} Returns the maximum value.
     * @example
     *
     * var objects = [{ 'n': 1 }, { 'n': 2 }];
     *
     * _.maxBy(objects, function(o) { return o.n; });
     * // => { 'n': 2 }
     *
     * // The `_.property` iteratee shorthand.
     * _.maxBy(objects, 'n');
     * // => { 'n': 2 }
     */
    function maxBy(array, iteratee) {
      return (array && array.length)
        ? baseExtremum(array, getIteratee(iteratee, 2), baseGt)
        : undefined;
    }

    /**
     * Computes the mean of the values in `array`.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Math
     * @param {Array} array The array to iterate over.
     * @returns {number} Returns the mean.
     * @example
     *
     * _.mean([4, 2, 8, 6]);
     * // => 5
     */
    function mean(array) {
      return baseMean(array, identity);
    }

    /**
     * This method is like `_.mean` except that it accepts `iteratee` which is
     * invoked for each element in `array` to generate the value to be averaged.
     * The iteratee is invoked with one argument: (value).
     *
     * @static
     * @memberOf _
     * @since 4.7.0
     * @category Math
     * @param {Array} array The array to iterate over.
     * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
     * @returns {number} Returns the mean.
     * @example
     *
     * var objects = [{ 'n': 4 }, { 'n': 2 }, { 'n': 8 }, { 'n': 6 }];
     *
     * _.meanBy(objects, function(o) { return o.n; });
     * // => 5
     *
     * // The `_.property` iteratee shorthand.
     * _.meanBy(objects, 'n');
     * // => 5
     */
    function meanBy(array, iteratee) {
      return baseMean(array, getIteratee(iteratee, 2));
    }

    /**
     * Computes the minimum value of `array`. If `array` is empty or falsey,
     * `undefined` is returned.
     *
     * @static
     * @since 0.1.0
     * @memberOf _
     * @category Math
     * @param {Array} array The array to iterate over.
     * @returns {*} Returns the minimum value.
     * @example
     *
     * _.min([4, 2, 8, 6]);
     * // => 2
     *
     * _.min([]);
     * // => undefined
     */
    function min(array) {
      return (array && array.length)
        ? baseExtremum(array, identity, baseLt)
        : undefined;
    }

    /**
     * This method is like `_.min` except that it accepts `iteratee` which is
     * invoked for each element in `array` to generate the criterion by which
     * the value is ranked. The iteratee is invoked with one argument: (value).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Math
     * @param {Array} array The array to iterate over.
     * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
     * @returns {*} Returns the minimum value.
     * @example
     *
     * var objects = [{ 'n': 1 }, { 'n': 2 }];
     *
     * _.minBy(objects, function(o) { return o.n; });
     * // => { 'n': 1 }
     *
     * // The `_.property` iteratee shorthand.
     * _.minBy(objects, 'n');
     * // => { 'n': 1 }
     */
    function minBy(array, iteratee) {
      return (array && array.length)
        ? baseExtremum(array, getIteratee(iteratee, 2), baseLt)
        : undefined;
    }

    /**
     * Multiply two numbers.
     *
     * @static
     * @memberOf _
     * @since 4.7.0
     * @category Math
     * @param {number} multiplier The first number in a multiplication.
     * @param {number} multiplicand The second number in a multiplication.
     * @returns {number} Returns the product.
     * @example
     *
     * _.multiply(6, 4);
     * // => 24
     */
    var multiply = createMathOperation(function(multiplier, multiplicand) {
      return multiplier * multiplicand;
    }, 1);

    /**
     * Computes `number` rounded to `precision`.
     *
     * @static
     * @memberOf _
     * @since 3.10.0
     * @category Math
     * @param {number} number The number to round.
     * @param {number} [precision=0] The precision to round to.
     * @returns {number} Returns the rounded number.
     * @example
     *
     * _.round(4.006);
     * // => 4
     *
     * _.round(4.006, 2);
     * // => 4.01
     *
     * _.round(4060, -2);
     * // => 4100
     */
    var round = createRound('round');

    /**
     * Subtract two numbers.
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Math
     * @param {number} minuend The first number in a subtraction.
     * @param {number} subtrahend The second number in a subtraction.
     * @returns {number} Returns the difference.
     * @example
     *
     * _.subtract(6, 4);
     * // => 2
     */
    var subtract = createMathOperation(function(minuend, subtrahend) {
      return minuend - subtrahend;
    }, 0);

    /**
     * Computes the sum of the values in `array`.
     *
     * @static
     * @memberOf _
     * @since 3.4.0
     * @category Math
     * @param {Array} array The array to iterate over.
     * @returns {number} Returns the sum.
     * @example
     *
     * _.sum([4, 2, 8, 6]);
     * // => 20
     */
    function sum(array) {
      return (array && array.length)
        ? baseSum(array, identity)
        : 0;
    }

    /**
     * This method is like `_.sum` except that it accepts `iteratee` which is
     * invoked for each element in `array` to generate the value to be summed.
     * The iteratee is invoked with one argument: (value).
     *
     * @static
     * @memberOf _
     * @since 4.0.0
     * @category Math
     * @param {Array} array The array to iterate over.
     * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
     * @returns {number} Returns the sum.
     * @example
     *
     * var objects = [{ 'n': 4 }, { 'n': 2 }, { 'n': 8 }, { 'n': 6 }];
     *
     * _.sumBy(objects, function(o) { return o.n; });
     * // => 20
     *
     * // The `_.property` iteratee shorthand.
     * _.sumBy(objects, 'n');
     * // => 20
     */
    function sumBy(array, iteratee) {
      return (array && array.length)
        ? baseSum(array, getIteratee(iteratee, 2))
        : 0;
    }

    /*------------------------------------------------------------------------*/

    // Add methods that return wrapped values in chain sequences.
    lodash.after = after;
    lodash.ary = ary;
    lodash.assign = assign;
    lodash.assignIn = assignIn;
    lodash.assignInWith = assignInWith;
    lodash.assignWith = assignWith;
    lodash.at = at;
    lodash.before = before;
    lodash.bind = bind;
    lodash.bindAll = bindAll;
    lodash.bindKey = bindKey;
    lodash.castArray = castArray;
    lodash.chain = chain;
    lodash.chunk = chunk;
    lodash.compact = compact;
    lodash.concat = concat;
    lodash.cond = cond;
    lodash.conforms = conforms;
    lodash.constant = constant;
    lodash.countBy = countBy;
    lodash.create = create;
    lodash.curry = curry;
    lodash.curryRight = curryRight;
    lodash.debounce = debounce;
    lodash.defaults = defaults;
    lodash.defaultsDeep = defaultsDeep;
    lodash.defer = defer;
    lodash.delay = delay;
    lodash.difference = difference;
    lodash.differenceBy = differenceBy;
    lodash.differenceWith = differenceWith;
    lodash.drop = drop;
    lodash.dropRight = dropRight;
    lodash.dropRightWhile = dropRightWhile;
    lodash.dropWhile = dropWhile;
    lodash.fill = fill;
    lodash.filter = filter;
    lodash.flatMap = flatMap;
    lodash.flatMapDeep = flatMapDeep;
    lodash.flatMapDepth = flatMapDepth;
    lodash.flatten = flatten;
    lodash.flattenDeep = flattenDeep;
    lodash.flattenDepth = flattenDepth;
    lodash.flip = flip;
    lodash.flow = flow;
    lodash.flowRight = flowRight;
    lodash.fromPairs = fromPairs;
    lodash.functions = functions;
    lodash.functionsIn = functionsIn;
    lodash.groupBy = groupBy;
    lodash.initial = initial;
    lodash.intersection = intersection;
    lodash.intersectionBy = intersectionBy;
    lodash.intersectionWith = intersectionWith;
    lodash.invert = invert;
    lodash.invertBy = invertBy;
    lodash.invokeMap = invokeMap;
    lodash.iteratee = iteratee;
    lodash.keyBy = keyBy;
    lodash.keys = keys;
    lodash.keysIn = keysIn;
    lodash.map = map;
    lodash.mapKeys = mapKeys;
    lodash.mapValues = mapValues;
    lodash.matches = matches;
    lodash.matchesProperty = matchesProperty;
    lodash.memoize = memoize;
    lodash.merge = merge;
    lodash.mergeWith = mergeWith;
    lodash.method = method;
    lodash.methodOf = methodOf;
    lodash.mixin = mixin;
    lodash.negate = negate;
    lodash.nthArg = nthArg;
    lodash.omit = omit;
    lodash.omitBy = omitBy;
    lodash.once = once;
    lodash.orderBy = orderBy;
    lodash.over = over;
    lodash.overArgs = overArgs;
    lodash.overEvery = overEvery;
    lodash.overSome = overSome;
    lodash.partial = partial;
    lodash.partialRight = partialRight;
    lodash.partition = partition;
    lodash.pick = pick;
    lodash.pickBy = pickBy;
    lodash.property = property;
    lodash.propertyOf = propertyOf;
    lodash.pull = pull;
    lodash.pullAll = pullAll;
    lodash.pullAllBy = pullAllBy;
    lodash.pullAllWith = pullAllWith;
    lodash.pullAt = pullAt;
    lodash.range = range;
    lodash.rangeRight = rangeRight;
    lodash.rearg = rearg;
    lodash.reject = reject;
    lodash.remove = remove;
    lodash.rest = rest;
    lodash.reverse = reverse;
    lodash.sampleSize = sampleSize;
    lodash.set = set;
    lodash.setWith = setWith;
    lodash.shuffle = shuffle;
    lodash.slice = slice;
    lodash.sortBy = sortBy;
    lodash.sortedUniq = sortedUniq;
    lodash.sortedUniqBy = sortedUniqBy;
    lodash.split = split;
    lodash.spread = spread;
    lodash.tail = tail;
    lodash.take = take;
    lodash.takeRight = takeRight;
    lodash.takeRightWhile = takeRightWhile;
    lodash.takeWhile = takeWhile;
    lodash.tap = tap;
    lodash.throttle = throttle;
    lodash.thru = thru;
    lodash.toArray = toArray;
    lodash.toPairs = toPairs;
    lodash.toPairsIn = toPairsIn;
    lodash.toPath = toPath;
    lodash.toPlainObject = toPlainObject;
    lodash.transform = transform;
    lodash.unary = unary;
    lodash.union = union;
    lodash.unionBy = unionBy;
    lodash.unionWith = unionWith;
    lodash.uniq = uniq;
    lodash.uniqBy = uniqBy;
    lodash.uniqWith = uniqWith;
    lodash.unset = unset;
    lodash.unzip = unzip;
    lodash.unzipWith = unzipWith;
    lodash.update = update;
    lodash.updateWith = updateWith;
    lodash.values = values;
    lodash.valuesIn = valuesIn;
    lodash.without = without;
    lodash.words = words;
    lodash.wrap = wrap;
    lodash.xor = xor;
    lodash.xorBy = xorBy;
    lodash.xorWith = xorWith;
    lodash.zip = zip;
    lodash.zipObject = zipObject;
    lodash.zipObjectDeep = zipObjectDeep;
    lodash.zipWith = zipWith;

    // Add aliases.
    lodash.entries = toPairs;
    lodash.entriesIn = toPairsIn;
    lodash.extend = assignIn;
    lodash.extendWith = assignInWith;

    // Add methods to `lodash.prototype`.
    mixin(lodash, lodash);

    /*------------------------------------------------------------------------*/

    // Add methods that return unwrapped values in chain sequences.
    lodash.add = add;
    lodash.attempt = attempt;
    lodash.camelCase = camelCase;
    lodash.capitalize = capitalize;
    lodash.ceil = ceil;
    lodash.clamp = clamp;
    lodash.clone = clone;
    lodash.cloneDeep = cloneDeep;
    lodash.cloneDeepWith = cloneDeepWith;
    lodash.cloneWith = cloneWith;
    lodash.conformsTo = conformsTo;
    lodash.deburr = deburr;
    lodash.defaultTo = defaultTo;
    lodash.divide = divide;
    lodash.endsWith = endsWith;
    lodash.eq = eq;
    lodash.escape = escape;
    lodash.escapeRegExp = escapeRegExp;
    lodash.every = every;
    lodash.find = find;
    lodash.findIndex = findIndex;
    lodash.findKey = findKey;
    lodash.findLast = findLast;
    lodash.findLastIndex = findLastIndex;
    lodash.findLastKey = findLastKey;
    lodash.floor = floor;
    lodash.forEach = forEach;
    lodash.forEachRight = forEachRight;
    lodash.forIn = forIn;
    lodash.forInRight = forInRight;
    lodash.forOwn = forOwn;
    lodash.forOwnRight = forOwnRight;
    lodash.get = get;
    lodash.gt = gt;
    lodash.gte = gte;
    lodash.has = has;
    lodash.hasIn = hasIn;
    lodash.head = head;
    lodash.identity = identity;
    lodash.includes = includes;
    lodash.indexOf = indexOf;
    lodash.inRange = inRange;
    lodash.invoke = invoke;
    lodash.isArguments = isArguments;
    lodash.isArray = isArray;
    lodash.isArrayBuffer = isArrayBuffer;
    lodash.isArrayLike = isArrayLike;
    lodash.isArrayLikeObject = isArrayLikeObject;
    lodash.isBoolean = isBoolean;
    lodash.isBuffer = isBuffer;
    lodash.isDate = isDate;
    lodash.isElement = isElement;
    lodash.isEmpty = isEmpty;
    lodash.isEqual = isEqual;
    lodash.isEqualWith = isEqualWith;
    lodash.isError = isError;
    lodash.isFinite = isFinite;
    lodash.isFunction = isFunction;
    lodash.isInteger = isInteger;
    lodash.isLength = isLength;
    lodash.isMap = isMap;
    lodash.isMatch = isMatch;
    lodash.isMatchWith = isMatchWith;
    lodash.isNaN = isNaN;
    lodash.isNative = isNative;
    lodash.isNil = isNil;
    lodash.isNull = isNull;
    lodash.isNumber = isNumber;
    lodash.isObject = isObject;
    lodash.isObjectLike = isObjectLike;
    lodash.isPlainObject = isPlainObject;
    lodash.isRegExp = isRegExp;
    lodash.isSafeInteger = isSafeInteger;
    lodash.isSet = isSet;
    lodash.isString = isString;
    lodash.isSymbol = isSymbol;
    lodash.isTypedArray = isTypedArray;
    lodash.isUndefined = isUndefined;
    lodash.isWeakMap = isWeakMap;
    lodash.isWeakSet = isWeakSet;
    lodash.join = join;
    lodash.kebabCase = kebabCase;
    lodash.last = last;
    lodash.lastIndexOf = lastIndexOf;
    lodash.lowerCase = lowerCase;
    lodash.lowerFirst = lowerFirst;
    lodash.lt = lt;
    lodash.lte = lte;
    lodash.max = max;
    lodash.maxBy = maxBy;
    lodash.mean = mean;
    lodash.meanBy = meanBy;
    lodash.min = min;
    lodash.minBy = minBy;
    lodash.stubArray = stubArray;
    lodash.stubFalse = stubFalse;
    lodash.stubObject = stubObject;
    lodash.stubString = stubString;
    lodash.stubTrue = stubTrue;
    lodash.multiply = multiply;
    lodash.nth = nth;
    lodash.noConflict = noConflict;
    lodash.noop = noop;
    lodash.now = now;
    lodash.pad = pad;
    lodash.padEnd = padEnd;
    lodash.padStart = padStart;
    lodash.parseInt = parseInt;
    lodash.random = random;
    lodash.reduce = reduce;
    lodash.reduceRight = reduceRight;
    lodash.repeat = repeat;
    lodash.replace = replace;
    lodash.result = result;
    lodash.round = round;
    lodash.runInContext = runInContext;
    lodash.sample = sample;
    lodash.size = size;
    lodash.snakeCase = snakeCase;
    lodash.some = some;
    lodash.sortedIndex = sortedIndex;
    lodash.sortedIndexBy = sortedIndexBy;
    lodash.sortedIndexOf = sortedIndexOf;
    lodash.sortedLastIndex = sortedLastIndex;
    lodash.sortedLastIndexBy = sortedLastIndexBy;
    lodash.sortedLastIndexOf = sortedLastIndexOf;
    lodash.startCase = startCase;
    lodash.startsWith = startsWith;
    lodash.subtract = subtract;
    lodash.sum = sum;
    lodash.sumBy = sumBy;
    lodash.template = template;
    lodash.times = times;
    lodash.toFinite = toFinite;
    lodash.toInteger = toInteger;
    lodash.toLength = toLength;
    lodash.toLower = toLower;
    lodash.toNumber = toNumber;
    lodash.toSafeInteger = toSafeInteger;
    lodash.toString = toString;
    lodash.toUpper = toUpper;
    lodash.trim = trim;
    lodash.trimEnd = trimEnd;
    lodash.trimStart = trimStart;
    lodash.truncate = truncate;
    lodash.unescape = unescape;
    lodash.uniqueId = uniqueId;
    lodash.upperCase = upperCase;
    lodash.upperFirst = upperFirst;

    // Add aliases.
    lodash.each = forEach;
    lodash.eachRight = forEachRight;
    lodash.first = head;

    mixin(lodash, (function() {
      var source = {};
      baseForOwn(lodash, function(func, methodName) {
        if (!hasOwnProperty.call(lodash.prototype, methodName)) {
          source[methodName] = func;
        }
      });
      return source;
    }()), { 'chain': false });

    /*------------------------------------------------------------------------*/

    /**
     * The semantic version number.
     *
     * @static
     * @memberOf _
     * @type {string}
     */
    lodash.VERSION = VERSION;

    // Assign default placeholders.
    arrayEach(['bind', 'bindKey', 'curry', 'curryRight', 'partial', 'partialRight'], function(methodName) {
      lodash[methodName].placeholder = lodash;
    });

    // Add `LazyWrapper` methods for `_.drop` and `_.take` variants.
    arrayEach(['drop', 'take'], function(methodName, index) {
      LazyWrapper.prototype[methodName] = function(n) {
        n = n === undefined ? 1 : nativeMax(toInteger(n), 0);

        var result = (this.__filtered__ && !index)
          ? new LazyWrapper(this)
          : this.clone();

        if (result.__filtered__) {
          result.__takeCount__ = nativeMin(n, result.__takeCount__);
        } else {
          result.__views__.push({
            'size': nativeMin(n, MAX_ARRAY_LENGTH),
            'type': methodName + (result.__dir__ < 0 ? 'Right' : '')
          });
        }
        return result;
      };

      LazyWrapper.prototype[methodName + 'Right'] = function(n) {
        return this.reverse()[methodName](n).reverse();
      };
    });

    // Add `LazyWrapper` methods that accept an `iteratee` value.
    arrayEach(['filter', 'map', 'takeWhile'], function(methodName, index) {
      var type = index + 1,
          isFilter = type == LAZY_FILTER_FLAG || type == LAZY_WHILE_FLAG;

      LazyWrapper.prototype[methodName] = function(iteratee) {
        var result = this.clone();
        result.__iteratees__.push({
          'iteratee': getIteratee(iteratee, 3),
          'type': type
        });
        result.__filtered__ = result.__filtered__ || isFilter;
        return result;
      };
    });

    // Add `LazyWrapper` methods for `_.head` and `_.last`.
    arrayEach(['head', 'last'], function(methodName, index) {
      var takeName = 'take' + (index ? 'Right' : '');

      LazyWrapper.prototype[methodName] = function() {
        return this[takeName](1).value()[0];
      };
    });

    // Add `LazyWrapper` methods for `_.initial` and `_.tail`.
    arrayEach(['initial', 'tail'], function(methodName, index) {
      var dropName = 'drop' + (index ? '' : 'Right');

      LazyWrapper.prototype[methodName] = function() {
        return this.__filtered__ ? new LazyWrapper(this) : this[dropName](1);
      };
    });

    LazyWrapper.prototype.compact = function() {
      return this.filter(identity);
    };

    LazyWrapper.prototype.find = function(predicate) {
      return this.filter(predicate).head();
    };

    LazyWrapper.prototype.findLast = function(predicate) {
      return this.reverse().find(predicate);
    };

    LazyWrapper.prototype.invokeMap = baseRest(function(path, args) {
      if (typeof path == 'function') {
        return new LazyWrapper(this);
      }
      return this.map(function(value) {
        return baseInvoke(value, path, args);
      });
    });

    LazyWrapper.prototype.reject = function(predicate) {
      return this.filter(negate(getIteratee(predicate)));
    };

    LazyWrapper.prototype.slice = function(start, end) {
      start = toInteger(start);

      var result = this;
      if (result.__filtered__ && (start > 0 || end < 0)) {
        return new LazyWrapper(result);
      }
      if (start < 0) {
        result = result.takeRight(-start);
      } else if (start) {
        result = result.drop(start);
      }
      if (end !== undefined) {
        end = toInteger(end);
        result = end < 0 ? result.dropRight(-end) : result.take(end - start);
      }
      return result;
    };

    LazyWrapper.prototype.takeRightWhile = function(predicate) {
      return this.reverse().takeWhile(predicate).reverse();
    };

    LazyWrapper.prototype.toArray = function() {
      return this.take(MAX_ARRAY_LENGTH);
    };

    // Add `LazyWrapper` methods to `lodash.prototype`.
    baseForOwn(LazyWrapper.prototype, function(func, methodName) {
      var checkIteratee = /^(?:filter|find|map|reject)|While$/.test(methodName),
          isTaker = /^(?:head|last)$/.test(methodName),
          lodashFunc = lodash[isTaker ? ('take' + (methodName == 'last' ? 'Right' : '')) : methodName],
          retUnwrapped = isTaker || /^find/.test(methodName);

      if (!lodashFunc) {
        return;
      }
      lodash.prototype[methodName] = function() {
        var value = this.__wrapped__,
            args = isTaker ? [1] : arguments,
            isLazy = value instanceof LazyWrapper,
            iteratee = args[0],
            useLazy = isLazy || isArray(value);

        var interceptor = function(value) {
          var result = lodashFunc.apply(lodash, arrayPush([value], args));
          return (isTaker && chainAll) ? result[0] : result;
        };

        if (useLazy && checkIteratee && typeof iteratee == 'function' && iteratee.length != 1) {
          // Avoid lazy use if the iteratee has a "length" value other than `1`.
          isLazy = useLazy = false;
        }
        var chainAll = this.__chain__,
            isHybrid = !!this.__actions__.length,
            isUnwrapped = retUnwrapped && !chainAll,
            onlyLazy = isLazy && !isHybrid;

        if (!retUnwrapped && useLazy) {
          value = onlyLazy ? value : new LazyWrapper(this);
          var result = func.apply(value, args);
          result.__actions__.push({ 'func': thru, 'args': [interceptor], 'thisArg': undefined });
          return new LodashWrapper(result, chainAll);
        }
        if (isUnwrapped && onlyLazy) {
          return func.apply(this, args);
        }
        result = this.thru(interceptor);
        return isUnwrapped ? (isTaker ? result.value()[0] : result.value()) : result;
      };
    });

    // Add `Array` methods to `lodash.prototype`.
    arrayEach(['pop', 'push', 'shift', 'sort', 'splice', 'unshift'], function(methodName) {
      var func = arrayProto[methodName],
          chainName = /^(?:push|sort|unshift)$/.test(methodName) ? 'tap' : 'thru',
          retUnwrapped = /^(?:pop|shift)$/.test(methodName);

      lodash.prototype[methodName] = function() {
        var args = arguments;
        if (retUnwrapped && !this.__chain__) {
          var value = this.value();
          return func.apply(isArray(value) ? value : [], args);
        }
        return this[chainName](function(value) {
          return func.apply(isArray(value) ? value : [], args);
        });
      };
    });

    // Map minified method names to their real names.
    baseForOwn(LazyWrapper.prototype, function(func, methodName) {
      var lodashFunc = lodash[methodName];
      if (lodashFunc) {
        var key = (lodashFunc.name + ''),
            names = realNames[key] || (realNames[key] = []);

        names.push({ 'name': methodName, 'func': lodashFunc });
      }
    });

    realNames[createHybrid(undefined, WRAP_BIND_KEY_FLAG).name] = [{
      'name': 'wrapper',
      'func': undefined
    }];

    // Add methods to `LazyWrapper`.
    LazyWrapper.prototype.clone = lazyClone;
    LazyWrapper.prototype.reverse = lazyReverse;
    LazyWrapper.prototype.value = lazyValue;

    // Add chain sequence methods to the `lodash` wrapper.
    lodash.prototype.at = wrapperAt;
    lodash.prototype.chain = wrapperChain;
    lodash.prototype.commit = wrapperCommit;
    lodash.prototype.next = wrapperNext;
    lodash.prototype.plant = wrapperPlant;
    lodash.prototype.reverse = wrapperReverse;
    lodash.prototype.toJSON = lodash.prototype.valueOf = lodash.prototype.value = wrapperValue;

    // Add lazy aliases.
    lodash.prototype.first = lodash.prototype.head;

    if (symIterator) {
      lodash.prototype[symIterator] = wrapperToIterator;
    }
    return lodash;
  });

  /*--------------------------------------------------------------------------*/

  // Export lodash.
  var _ = runInContext();

  // Some AMD build optimizers, like r.js, check for condition patterns like:
  if (typeof define == 'function' && typeof define.amd == 'object' && define.amd) {
    // Expose Lodash on the global object to prevent errors when Lodash is
    // loaded by a script tag in the presence of an AMD loader.
    // See http://requirejs.org/docs/errors.html#mismatch for more details.
    // Use `_.noConflict` to remove Lodash from the global object.
    root._ = _;

    // Define as an anonymous module so, through path mapping, it can be
    // referenced as the "underscore" module.
    define(function() {
      return _;
    });
  }
  // Check for `exports` after `define` in case a build optimizer adds it.
  else if (freeModule) {
    // Export for Node.js.
    (freeModule.exports = _)._ = _;
    // Export for CommonJS support.
    freeExports._ = _;
  }
  else {
    // Export to the global object.
    root._ = _;
  }
}.call(this));

}).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
},{}],3:[function(require,module,exports){
(function (process){
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

// resolves . and .. elements in a path array with directory names there
// must be no slashes, empty elements, or device names (c:\) in the array
// (so also no leading and trailing slashes - it does not distinguish
// relative and absolute paths)
function normalizeArray(parts, allowAboveRoot) {
  // if the path tries to go above the root, `up` ends up > 0
  var up = 0;
  for (var i = parts.length - 1; i >= 0; i--) {
    var last = parts[i];
    if (last === '.') {
      parts.splice(i, 1);
    } else if (last === '..') {
      parts.splice(i, 1);
      up++;
    } else if (up) {
      parts.splice(i, 1);
      up--;
    }
  }

  // if the path is allowed to go above the root, restore leading ..s
  if (allowAboveRoot) {
    for (; up--; up) {
      parts.unshift('..');
    }
  }

  return parts;
}

// Split a filename into [root, dir, basename, ext], unix version
// 'root' is just a slash, or nothing.
var splitPathRe =
    /^(\/?|)([\s\S]*?)((?:\.{1,2}|[^\/]+?|)(\.[^.\/]*|))(?:[\/]*)$/;
var splitPath = function(filename) {
  return splitPathRe.exec(filename).slice(1);
};

// path.resolve([from ...], to)
// posix version
exports.resolve = function() {
  var resolvedPath = '',
      resolvedAbsolute = false;

  for (var i = arguments.length - 1; i >= -1 && !resolvedAbsolute; i--) {
    var path = (i >= 0) ? arguments[i] : process.cwd();

    // Skip empty and invalid entries
    if (typeof path !== 'string') {
      throw new TypeError('Arguments to path.resolve must be strings');
    } else if (!path) {
      continue;
    }

    resolvedPath = path + '/' + resolvedPath;
    resolvedAbsolute = path.charAt(0) === '/';
  }

  // At this point the path should be resolved to a full absolute path, but
  // handle relative paths to be safe (might happen when process.cwd() fails)

  // Normalize the path
  resolvedPath = normalizeArray(filter(resolvedPath.split('/'), function(p) {
    return !!p;
  }), !resolvedAbsolute).join('/');

  return ((resolvedAbsolute ? '/' : '') + resolvedPath) || '.';
};

// path.normalize(path)
// posix version
exports.normalize = function(path) {
  var isAbsolute = exports.isAbsolute(path),
      trailingSlash = substr(path, -1) === '/';

  // Normalize the path
  path = normalizeArray(filter(path.split('/'), function(p) {
    return !!p;
  }), !isAbsolute).join('/');

  if (!path && !isAbsolute) {
    path = '.';
  }
  if (path && trailingSlash) {
    path += '/';
  }

  return (isAbsolute ? '/' : '') + path;
};

// posix version
exports.isAbsolute = function(path) {
  return path.charAt(0) === '/';
};

// posix version
exports.join = function() {
  var paths = Array.prototype.slice.call(arguments, 0);
  return exports.normalize(filter(paths, function(p, index) {
    if (typeof p !== 'string') {
      throw new TypeError('Arguments to path.join must be strings');
    }
    return p;
  }).join('/'));
};


// path.relative(from, to)
// posix version
exports.relative = function(from, to) {
  from = exports.resolve(from).substr(1);
  to = exports.resolve(to).substr(1);

  function trim(arr) {
    var start = 0;
    for (; start < arr.length; start++) {
      if (arr[start] !== '') break;
    }

    var end = arr.length - 1;
    for (; end >= 0; end--) {
      if (arr[end] !== '') break;
    }

    if (start > end) return [];
    return arr.slice(start, end - start + 1);
  }

  var fromParts = trim(from.split('/'));
  var toParts = trim(to.split('/'));

  var length = Math.min(fromParts.length, toParts.length);
  var samePartsLength = length;
  for (var i = 0; i < length; i++) {
    if (fromParts[i] !== toParts[i]) {
      samePartsLength = i;
      break;
    }
  }

  var outputParts = [];
  for (var i = samePartsLength; i < fromParts.length; i++) {
    outputParts.push('..');
  }

  outputParts = outputParts.concat(toParts.slice(samePartsLength));

  return outputParts.join('/');
};

exports.sep = '/';
exports.delimiter = ':';

exports.dirname = function(path) {
  var result = splitPath(path),
      root = result[0],
      dir = result[1];

  if (!root && !dir) {
    // No dirname whatsoever
    return '.';
  }

  if (dir) {
    // It has a dirname, strip trailing slash
    dir = dir.substr(0, dir.length - 1);
  }

  return root + dir;
};


exports.basename = function(path, ext) {
  var f = splitPath(path)[2];
  // TODO: make this comparison case-insensitive on windows?
  if (ext && f.substr(-1 * ext.length) === ext) {
    f = f.substr(0, f.length - ext.length);
  }
  return f;
};


exports.extname = function(path) {
  return splitPath(path)[3];
};

function filter (xs, f) {
    if (xs.filter) return xs.filter(f);
    var res = [];
    for (var i = 0; i < xs.length; i++) {
        if (f(xs[i], i, xs)) res.push(xs[i]);
    }
    return res;
}

// String.prototype.substr - negative index don't work in IE8
var substr = 'ab'.substr(-1) === 'b'
    ? function (str, start, len) { return str.substr(start, len) }
    : function (str, start, len) {
        if (start < 0) start = str.length + start;
        return str.substr(start, len);
    }
;

}).call(this,require('_process'))
},{"_process":4}],4:[function(require,module,exports){
// shim for using process in browser
var process = module.exports = {};

// cached from whatever global is present so that test runners that stub it
// don't break things.  But we need to wrap it in a try catch in case it is
// wrapped in strict mode code which doesn't define any globals.  It's inside a
// function because try/catches deoptimize in certain engines.

var cachedSetTimeout;
var cachedClearTimeout;

function defaultSetTimout() {
    throw new Error('setTimeout has not been defined');
}
function defaultClearTimeout () {
    throw new Error('clearTimeout has not been defined');
}
(function () {
    try {
        if (typeof setTimeout === 'function') {
            cachedSetTimeout = setTimeout;
        } else {
            cachedSetTimeout = defaultSetTimout;
        }
    } catch (e) {
        cachedSetTimeout = defaultSetTimout;
    }
    try {
        if (typeof clearTimeout === 'function') {
            cachedClearTimeout = clearTimeout;
        } else {
            cachedClearTimeout = defaultClearTimeout;
        }
    } catch (e) {
        cachedClearTimeout = defaultClearTimeout;
    }
} ())
function runTimeout(fun) {
    if (cachedSetTimeout === setTimeout) {
        //normal enviroments in sane situations
        return setTimeout(fun, 0);
    }
    // if setTimeout wasn't available but was latter defined
    if ((cachedSetTimeout === defaultSetTimout || !cachedSetTimeout) && setTimeout) {
        cachedSetTimeout = setTimeout;
        return setTimeout(fun, 0);
    }
    try {
        // when when somebody has screwed with setTimeout but no I.E. maddness
        return cachedSetTimeout(fun, 0);
    } catch(e){
        try {
            // When we are in I.E. but the script has been evaled so I.E. doesn't trust the global object when called normally
            return cachedSetTimeout.call(null, fun, 0);
        } catch(e){
            // same as above but when it's a version of I.E. that must have the global object for 'this', hopfully our context correct otherwise it will throw a global error
            return cachedSetTimeout.call(this, fun, 0);
        }
    }


}
function runClearTimeout(marker) {
    if (cachedClearTimeout === clearTimeout) {
        //normal enviroments in sane situations
        return clearTimeout(marker);
    }
    // if clearTimeout wasn't available but was latter defined
    if ((cachedClearTimeout === defaultClearTimeout || !cachedClearTimeout) && clearTimeout) {
        cachedClearTimeout = clearTimeout;
        return clearTimeout(marker);
    }
    try {
        // when when somebody has screwed with setTimeout but no I.E. maddness
        return cachedClearTimeout(marker);
    } catch (e){
        try {
            // When we are in I.E. but the script has been evaled so I.E. doesn't  trust the global object when called normally
            return cachedClearTimeout.call(null, marker);
        } catch (e){
            // same as above but when it's a version of I.E. that must have the global object for 'this', hopfully our context correct otherwise it will throw a global error.
            // Some versions of I.E. have different rules for clearTimeout vs setTimeout
            return cachedClearTimeout.call(this, marker);
        }
    }



}
var queue = [];
var draining = false;
var currentQueue;
var queueIndex = -1;

function cleanUpNextTick() {
    if (!draining || !currentQueue) {
        return;
    }
    draining = false;
    if (currentQueue.length) {
        queue = currentQueue.concat(queue);
    } else {
        queueIndex = -1;
    }
    if (queue.length) {
        drainQueue();
    }
}

function drainQueue() {
    if (draining) {
        return;
    }
    var timeout = runTimeout(cleanUpNextTick);
    draining = true;

    var len = queue.length;
    while(len) {
        currentQueue = queue;
        queue = [];
        while (++queueIndex < len) {
            if (currentQueue) {
                currentQueue[queueIndex].run();
            }
        }
        queueIndex = -1;
        len = queue.length;
    }
    currentQueue = null;
    draining = false;
    runClearTimeout(timeout);
}

process.nextTick = function (fun) {
    var args = new Array(arguments.length - 1);
    if (arguments.length > 1) {
        for (var i = 1; i < arguments.length; i++) {
            args[i - 1] = arguments[i];
        }
    }
    queue.push(new Item(fun, args));
    if (queue.length === 1 && !draining) {
        runTimeout(drainQueue);
    }
};

// v8 likes predictible objects
function Item(fun, array) {
    this.fun = fun;
    this.array = array;
}
Item.prototype.run = function () {
    this.fun.apply(null, this.array);
};
process.title = 'browser';
process.browser = true;
process.env = {};
process.argv = [];
process.version = ''; // empty string to avoid regexp issues
process.versions = {};

function noop() {}

process.on = noop;
process.addListener = noop;
process.once = noop;
process.off = noop;
process.removeListener = noop;
process.removeAllListeners = noop;
process.emit = noop;

process.binding = function (name) {
    throw new Error('process.binding is not supported');
};

process.cwd = function () { return '/' };
process.chdir = function (dir) {
    throw new Error('process.chdir is not supported');
};
process.umask = function() { return 0; };

},{}],5:[function(require,module,exports){
'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});

var _line = require('./line');

Object.defineProperty(exports, 'Line', {
  enumerable: true,
  get: function get() {
    return _line.Line;
  }
});

var _matrix = require('./matrix');

Object.defineProperty(exports, 'Matrix', {
  enumerable: true,
  get: function get() {
    return _matrix.Matrix;
  }
});

var _plane = require('./plane');

Object.defineProperty(exports, 'Plane', {
  enumerable: true,
  get: function get() {
    return _plane.Plane;
  }
});

var _sylvester = require('./sylvester');

Object.defineProperty(exports, 'Sylvester', {
  enumerable: true,
  get: function get() {
    return _sylvester.Sylvester;
  }
});

var _vector = require('./vector');

Object.defineProperty(exports, 'Vector', {
  enumerable: true,
  get: function get() {
    return _vector.Vector;
  }
});
},{"./line":6,"./matrix":7,"./plane":8,"./sylvester":9,"./vector":10}],6:[function(require,module,exports){
'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.Segment = exports.Line = undefined;

var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }(); // Copyright (c) 2011, Chris Umbel, James Coglan


var _vector = require('./vector');

var _matrix = require('./matrix');

var _plane = require('./plane');

var _sylvester = require('./sylvester');

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

// Line class - depends on Vector, and some methods require Matrix and Plane.
var Line = exports.Line = function () {
  function Line() {
    _classCallCheck(this, Line);
  }

  _createClass(Line, [{
    key: 'eql',

    // Returns true if the argument occupies the same space as the line
    value: function eql(line) {
      return this.isParallelTo(line) && this.contains(line.anchor);
    }

    // Returns a copy of the line

  }, {
    key: 'dup',
    value: function dup() {
      return Line.create(this.anchor, this.direction);
    }

    // Returns the result of translating the line by the given vector/array

  }, {
    key: 'translate',
    value: function translate(vector) {
      var V = vector.elements || vector;
      return Line.create([this.anchor.elements[0] + V[0], this.anchor.elements[1] + V[1], this.anchor.elements[2] + (V[2] || 0)], this.direction);
    }

    // Returns true if the line is parallel to the argument. Here, 'parallel to'
    // means that the argument's direction is either parallel or antiparallel to
    // the line's own direction. A line is parallel to a plane if the two do not
    // have a unique intersection.

  }, {
    key: 'isParallelTo',
    value: function isParallelTo(obj) {
      if (obj.normal || obj.start && obj.end) {
        return obj.isParallelTo(this);
      }
      var theta = this.direction.angleFrom(obj.direction);
      return Math.abs(theta) <= _sylvester.Sylvester.precision || Math.abs(theta - Math.PI) <= _sylvester.Sylvester.precision;
    }

    // Returns the line's perpendicular distance from the argument,
    // which can be a point, a line or a plane

  }, {
    key: 'distanceFrom',
    value: function distanceFrom(obj) {
      if (obj.normal || obj.start && obj.end) {
        return obj.distanceFrom(this);
      }
      if (obj.direction) {
        // obj is a line
        if (this.isParallelTo(obj)) {
          return this.distanceFrom(obj.anchor);
        }
        var N = this.direction.cross(obj.direction).toUnitVector().elements;
        var _A = this.anchor.elements;
        var B = obj.anchor.elements;
        return Math.abs((_A[0] - B[0]) * N[0] + (_A[1] - B[1]) * N[1] + (_A[2] - B[2]) * N[2]);
      }

      // obj is a point
      var P = obj.elements || obj;
      var A = this.anchor.elements;
      var D = this.direction.elements;
      var PA1 = P[0] - A[0];
      var PA2 = P[1] - A[1];
      var PA3 = (P[2] || 0) - A[2];
      var modPA = Math.sqrt(PA1 * PA1 + PA2 * PA2 + PA3 * PA3);
      if (modPA === 0) {
        return 0;
      }

      // Assumes direction vector is normalized
      var cosTheta = (PA1 * D[0] + PA2 * D[1] + PA3 * D[2]) / modPA;
      var sin2 = 1 - cosTheta * cosTheta;
      return Math.abs(modPA * Math.sqrt(sin2 < 0 ? 0 : sin2));
    }

    // Returns true iff the argument is a point on the line, or if the argument
    // is a line segment lying within the receiver

  }, {
    key: 'contains',
    value: function contains(obj) {
      if (obj.start && obj.end) {
        return this.contains(obj.start) && this.contains(obj.end);
      }
      var dist = this.distanceFrom(obj);
      return dist !== null && dist <= _sylvester.Sylvester.precision;
    }

    // Returns the distance from the anchor of the given point. Negative values are
    // returned for points that are in the opposite direction to the line's direction from
    // the line's anchor point.

  }, {
    key: 'positionOf',
    value: function positionOf(point) {
      if (!this.contains(point)) {
        return null;
      }
      var P = point.elements || point;
      var A = this.anchor.elements;
      var D = this.direction.elements;
      return (P[0] - A[0]) * D[0] + (P[1] - A[1]) * D[1] + ((P[2] || 0) - A[2]) * D[2];
    }

    // Returns true iff the line lies in the given plane

  }, {
    key: 'liesIn',
    value: function liesIn(plane) {
      return plane.contains(this);
    }

    // Returns true iff the line has a unique point of intersection with the argument

  }, {
    key: 'intersects',
    value: function intersects(obj) {
      if (obj.normal) {
        return obj.intersects(this);
      }
      return !this.isParallelTo(obj) && this.distanceFrom(obj) <= _sylvester.Sylvester.precision;
    }

    // Returns the unique intersection point with the argument, if one exists

  }, {
    key: 'intersectionWith',
    value: function intersectionWith(obj) {
      if (obj.normal || obj.start && obj.end) {
        return obj.intersectionWith(this);
      }
      if (!this.intersects(obj)) {
        return null;
      }
      var P = this.anchor.elements;
      var X = this.direction.elements;
      var Q = obj.anchor.elements;
      var Y = obj.direction.elements;
      var X1 = X[0];
      var X2 = X[1];
      var X3 = X[2];
      var Y1 = Y[0];
      var Y2 = Y[1];
      var Y3 = Y[2];
      var PsubQ1 = P[0] - Q[0];
      var PsubQ2 = P[1] - Q[1];
      var PsubQ3 = P[2] - Q[2];
      var XdotQsubP = -X1 * PsubQ1 - X2 * PsubQ2 - X3 * PsubQ3;
      var YdotPsubQ = Y1 * PsubQ1 + Y2 * PsubQ2 + Y3 * PsubQ3;
      var XdotX = X1 * X1 + X2 * X2 + X3 * X3;
      var YdotY = Y1 * Y1 + Y2 * Y2 + Y3 * Y3;
      var XdotY = X1 * Y1 + X2 * Y2 + X3 * Y3;
      var k = (XdotQsubP * YdotY / XdotX + XdotY * YdotPsubQ) / (YdotY - XdotY * XdotY);

      return _vector.Vector.create([P[0] + k * X1, P[1] + k * X2, P[2] + k * X3]);
    }

    // Returns the point on the line that is closest to the given point or line/line segment

  }, {
    key: 'pointClosestTo',
    value: function pointClosestTo(obj) {
      if (obj.start && obj.end) {
        // obj is a line segment
        var _P = obj.pointClosestTo(this);
        return _P === null ? null : this.pointClosestTo(_P);
      }
      if (obj.direction) {
        // obj is a line
        if (this.intersects(obj)) {
          return this.intersectionWith(obj);
        }
        if (this.isParallelTo(obj)) {
          return null;
        }
        var _D = this.direction.elements;
        var E = obj.direction.elements;
        var _D2 = _D[0];
        var _D3 = _D[1];
        var _D4 = _D[2];
        var E1 = E[0];
        var E2 = E[1];
        var E3 = E[2];

        // Create plane containing obj and the shared normal and intersect this with it
        // Thank you: http://www.cgafaq.info/wiki/Line-line_distance
        var _x = _D4 * E1 - _D2 * E3;
        var _y = _D2 * E2 - _D3 * E1;
        var _z = _D3 * E3 - _D4 * E2;
        var N = [_x * E3 - _y * E2, _y * E1 - _z * E3, _z * E2 - _x * E1];
        var _P2 = _plane.Plane.create(obj.anchor, N);
        return _P2.intersectionWith(this);
      }

      // obj is a point
      var P = obj.elements || obj;
      if (this.contains(P)) {
        return _vector.Vector.create(P);
      }
      var A = this.anchor.elements;
      var D = this.direction.elements;
      var D1 = D[0];
      var D2 = D[1];
      var D3 = D[2];
      var A1 = A[0];
      var A2 = A[1];
      var A3 = A[2];
      var x = D1 * (P[1] - A2) - D2 * (P[0] - A1);
      var y = D2 * ((P[2] || 0) - A3) - D3 * (P[1] - A2);
      var z = D3 * (P[0] - A1) - D1 * ((P[2] || 0) - A3);
      var V = _vector.Vector.create([D2 * x - D3 * z, D3 * y - D1 * x, D1 * z - D2 * y]);
      var k = this.distanceFrom(P) / V.modulus();
      return _vector.Vector.create([P[0] + V.elements[0] * k, P[1] + V.elements[1] * k, (P[2] || 0) + V.elements[2] * k]);
    }

    // Returns a copy of the line rotated by t radians about the given line. Works by
    // finding the argument's closest point to this line's anchor point (call this C) and
    // rotating the anchor about C. Also rotates the line's direction about the argument's.
    // Be careful with this - the rotation axis' direction affects the outcome!

  }, {
    key: 'rotate',
    value: function rotate(t, line) {
      // If we're working in 2D
      if (typeof line.direction === 'undefined') {
        line = Line.create(line.to3D(), _vector.Vector.k);
      }
      var R = _matrix.Matrix.Rotation(t, line.direction).elements;
      var C = line.pointClosestTo(this.anchor).elements;
      var A = this.anchor.elements;
      var D = this.direction.elements;
      var C1 = C[0];
      var C2 = C[1];
      var C3 = C[2];
      var A1 = A[0];
      var A2 = A[1];
      var A3 = A[2];
      var x = A1 - C1;
      var y = A2 - C2;
      var z = A3 - C3;
      return Line.create([C1 + R[0][0] * x + R[0][1] * y + R[0][2] * z, C2 + R[1][0] * x + R[1][1] * y + R[1][2] * z, C3 + R[2][0] * x + R[2][1] * y + R[2][2] * z], [R[0][0] * D[0] + R[0][1] * D[1] + R[0][2] * D[2], R[1][0] * D[0] + R[1][1] * D[1] + R[1][2] * D[2], R[2][0] * D[0] + R[2][1] * D[1] + R[2][2] * D[2]]);
    }

    // Returns a copy of the line with its direction vector reversed.
    // Useful when using lines for rotations.

  }, {
    key: 'reverse',
    value: function reverse() {
      return Line.create(this.anchor, this.direction.x(-1));
    }

    // Returns the line's reflection in the given point or line

  }, {
    key: 'reflectionIn',
    value: function reflectionIn(obj) {
      if (obj.normal) {
        // obj is a plane
        var A = this.anchor.elements;

        var D = this.direction.elements;
        var A1 = A[0];
        var A2 = A[1];
        var A3 = A[2];
        var D1 = D[0];
        var D2 = D[1];
        var D3 = D[2];
        var newA = this.anchor.reflectionIn(obj).elements;

        // Add the line's direction vector to its anchor, then mirror that in the plane
        var AD1 = A1 + D1;

        var AD2 = A2 + D2;
        var AD3 = A3 + D3;
        var Q = obj.pointClosestTo([AD1, AD2, AD3]).elements;
        var newD = [Q[0] + (Q[0] - AD1) - newA[0], Q[1] + (Q[1] - AD2) - newA[1], Q[2] + (Q[2] - AD3) - newA[2]];
        return Line.create(newA, newD);
      }
      if (obj.direction) {
        // obj is a line - reflection obtained by rotating PI radians about obj
        return this.rotate(Math.PI, obj);
      }

      // obj is a point - just reflect the line's anchor in it
      var P = obj.elements || obj;
      return Line.create(this.anchor.reflectionIn([P[0], P[1], P[2] || 0]), this.direction);
    }

    // Set the line's anchor point and direction.

  }, {
    key: 'setVectors',
    value: function setVectors(anchor, direction) {
      // Need to do this so that line's properties are not
      // references to the arguments passed in
      anchor = _vector.Vector.create(anchor);
      direction = _vector.Vector.create(direction);
      if (anchor.elements.length === 2) {
        anchor.elements.push(0);
      }
      if (direction.elements.length === 2) {
        direction.elements.push(0);
      }
      if (anchor.elements.length > 3 || direction.elements.length > 3) {
        return null;
      }
      var mod = direction.modulus();
      if (mod === 0) {
        return null;
      }
      this.anchor = anchor;
      this.direction = _vector.Vector.create([direction.elements[0] / mod, direction.elements[1] / mod, direction.elements[2] / mod]);
      return this;
    }

    // Constructor function

  }], [{
    key: 'create',
    value: function create(anchor, direction) {
      var L = new Line();
      return L.setVectors(anchor, direction);
    }
  }]);

  return Line;
}();

var Segment = exports.Segment = function () {
  function Segment() {
    _classCallCheck(this, Segment);
  }

  _createClass(Segment, [{
    key: 'eql',

    // Returns true iff the line segment is equal to the argument
    value: function eql(segment) {
      return this.start.eql(segment.start) && this.end.eql(segment.end) || this.start.eql(segment.end) && this.end.eql(segment.start);
    }

    // Returns a copy of the line segment

  }, {
    key: 'dup',
    value: function dup() {
      return Segment.create(this.start, this.end);
    }

    // Returns the length of the line segment

  }, {
    key: 'length',
    value: function length() {
      var A = this.start.elements;
      var B = this.end.elements;
      var C1 = B[0] - A[0];
      var C2 = B[1] - A[1];
      var C3 = B[2] - A[2];
      return Math.sqrt(C1 * C1 + C2 * C2 + C3 * C3);
    }

    // Returns the line segment as a vector equal to its
    // end point relative to its endpoint

  }, {
    key: 'toVector',
    value: function toVector() {
      var A = this.start.elements;
      var B = this.end.elements;
      return _vector.Vector.create([B[0] - A[0], B[1] - A[1], B[2] - A[2]]);
    }

    // Returns the segment's midpoint as a vector

  }, {
    key: 'midpoint',
    value: function midpoint() {
      var A = this.start.elements;
      var B = this.end.elements;
      return _vector.Vector.create([(B[0] + A[0]) / 2, (B[1] + A[1]) / 2, (B[2] + A[2]) / 2]);
    }

    // Returns the plane that bisects the segment

  }, {
    key: 'bisectingPlane',
    value: function bisectingPlane() {
      return _plane.Plane.create(this.midpoint(), this.toVector());
    }

    // Returns the result of translating the line by the given vector/array

  }, {
    key: 'translate',
    value: function translate(vector) {
      var V = vector.elements || vector;
      var S = this.start.elements;
      var E = this.end.elements;
      return Segment.create([S[0] + V[0], S[1] + V[1], S[2] + (V[2] || 0)], [E[0] + V[0], E[1] + V[1], E[2] + (V[2] || 0)]);
    }

    // Returns true iff the line segment is parallel to the argument. It simply forwards
    // the method call onto its line property.

  }, {
    key: 'isParallelTo',
    value: function isParallelTo(obj) {
      return this.line.isParallelTo(obj);
    }

    // Returns the distance between the argument and the line segment's closest point to the argument

  }, {
    key: 'distanceFrom',
    value: function distanceFrom(obj) {
      var P = this.pointClosestTo(obj);
      return P === null ? null : P.distanceFrom(obj);
    }

    // Returns true iff the given point lies on the segment

  }, {
    key: 'contains',
    value: function contains(obj) {
      if (obj.start && obj.end) {
        return this.contains(obj.start) && this.contains(obj.end);
      }
      var P = (obj.elements || obj).slice();
      if (P.length === 2) {
        P.push(0);
      }
      if (this.start.eql(P)) {
        return true;
      }
      var S = this.start.elements;
      var V = _vector.Vector.create([S[0] - P[0], S[1] - P[1], S[2] - (P[2] || 0)]);
      var vect = this.toVector();
      return V.isAntiparallelTo(vect) && V.modulus() <= vect.modulus();
    }

    // Returns true iff the line segment intersects the argument

  }, {
    key: 'intersects',
    value: function intersects(obj) {
      return this.intersectionWith(obj) !== null;
    }

    // Returns the unique point of intersection with the argument

  }, {
    key: 'intersectionWith',
    value: function intersectionWith(obj) {
      if (!this.line.intersects(obj)) {
        return null;
      }
      var P = this.line.intersectionWith(obj);
      return this.contains(P) ? P : null;
    }

    // Returns the point on the line segment closest to the given object

  }, {
    key: 'pointClosestTo',
    value: function pointClosestTo(obj) {
      if (obj.normal) {
        // obj is a plane
        var V = this.line.intersectionWith(obj);
        if (V === null) {
          return null;
        }
        return this.pointClosestTo(V);
      }

      // obj is a line (segment) or point
      var P = this.line.pointClosestTo(obj);
      if (P === null) {
        return null;
      }
      if (this.contains(P)) {
        return P;
      }

      return (this.line.positionOf(P) < 0 ? this.start : this.end).dup();
    }

    // Set the start and end-points of the segment

  }, {
    key: 'setPoints',
    value: function setPoints(startPoint, endPoint) {
      startPoint = _vector.Vector.create(startPoint).to3D();
      endPoint = _vector.Vector.create(endPoint).to3D();
      if (startPoint === null || endPoint === null) {
        return null;
      }
      this.line = Line.create(startPoint, endPoint.subtract(startPoint));
      this.start = startPoint;
      this.end = endPoint;
      return this;
    }

    // Constructor function

  }], [{
    key: 'create',
    value: function create(v1, v2) {
      var S = new Segment();
      return S.setPoints(v1, v2);
    }
  }]);

  return Segment;
}();

// Axes


Line.X = Line.create(_vector.Vector.Zero(3), _vector.Vector.i);
Line.Y = Line.create(_vector.Vector.Zero(3), _vector.Vector.j);
Line.Z = Line.create(_vector.Vector.Zero(3), _vector.Vector.k);
Line.Segment = Segment;
},{"./matrix":7,"./plane":8,"./sylvester":9,"./vector":10}],7:[function(require,module,exports){
'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.Matrix = undefined;

var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();

var _fs = require('fs');

var fs = _interopRequireWildcard(_fs);

var _sylvester = require('./sylvester');

var _vector = require('./vector');

function _interopRequireWildcard(obj) { if (obj && obj.__esModule) { return obj; } else { var newObj = {}; if (obj != null) { for (var key in obj) { if (Object.prototype.hasOwnProperty.call(obj, key)) newObj[key] = obj[key]; } } newObj.default = obj; return newObj; } }

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

var lapack = function () {
  try {
    return require('lapack');
  } catch (err) {
    return null;
  }
}();

function sign(x) {
  return x < 0 ? -1 : 1;
}

// augment a matrix M with identity rows/cols
function identSize(M, m, n, k) {
  var e = M.elements;
  var i = k - 1;

  while (i--) {
    var row = [];

    for (var j = 0; j < n; j++) {
      row.push(j === i ? 1 : 0);
    }

    e.unshift(row);
  }

  for (var _i = k - 1; _i < m; _i++) {
    while (e[_i].length < n) {
      e[_i].unshift(0);
    }
  }

  return Matrix.create(e); // eslint-disable-line no-use-before-define
}

function pca(X) {
  var Sigma = X.transpose().x(X).x(1 / X.rows());
  var svd = Sigma.svd();
  return {
    U: svd.U,
    S: svd.S
  };
}

var Matrix = exports.Matrix = function () {
  function Matrix() {
    _classCallCheck(this, Matrix);
  }

  _createClass(Matrix, [{
    key: 'solve',

    // solve a system of linear equations (work in progress)
    value: function solve(b) {
      var lu = this.lu();
      b = lu.P.x(b);
      var y = lu.L.forwardSubstitute(b);
      var x = lu.U.backSubstitute(y);
      return lu.P.x(x);
      // return this.inv().x(b);
    }

    // project a matrix onto a lower dim

  }, {
    key: 'pcaProject',
    value: function pcaProject(k) {
      var U = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : pca(this).U;

      var Ureduce = U.slice(1, U.rows(), 1, k);
      return {
        Z: this.x(Ureduce),
        U: U
      };
    }

    // recover a matrix to a higher dimension

  }, {
    key: 'pcaRecover',
    value: function pcaRecover(U) {
      var k = this.cols();
      var Ureduce = U.slice(1, U.rows(), 1, k);
      return this.x(Ureduce.transpose());
    }

    // grab the upper triangular part of the matrix

  }, {
    key: 'triu',
    value: function triu(k) {
      if (!k) {
        k = 0;
      }

      return this.map(function (x, i, j) {
        return j - i >= k ? x : 0;
      });
    }

    // unroll a matrix into a vector

  }, {
    key: 'unroll',
    value: function unroll() {
      var v = [];

      for (var i = 1; i <= this.cols(); i++) {
        for (var j = 1; j <= this.rows(); j++) {
          v.push(this.e(j, i));
        }
      }

      return _vector.Vector.create(v);
    }

    // return a sub-block of the matrix

  }, {
    key: 'slice',
    value: function slice(startRow, endRow, startCol, endCol) {
      var x = [];

      if (endRow === 0) {
        endRow = this.rows();
      }

      if (endCol === 0) {
        endCol = this.cols();
      }

      for (var i = startRow; i <= endRow; i++) {
        var row = [];

        for (var j = startCol; j <= endCol; j++) {
          row.push(this.e(i, j));
        }

        x.push(row);
      }

      return Matrix.create(x);
    }

    // Returns element (i,j) of the matrix

  }, {
    key: 'e',
    value: function e(i, j) {
      if (i < 1 || i > this.elements.length || j < 1 || j > this.elements[0].length) {
        return null;
      }
      return this.elements[i - 1][j - 1];
    }

    // Returns row k of the matrix as a vector

  }, {
    key: 'row',
    value: function row(i) {
      if (i > this.elements.length) {
        return null;
      }
      return _vector.Vector.create(this.elements[i - 1]);
    }

    // Returns column k of the matrix as a vector

  }, {
    key: 'col',
    value: function col(j) {
      if (j > this.elements[0].length) {
        return null;
      }
      var col = [];
      var n = this.elements.length;
      for (var i = 0; i < n; i++) {
        col.push(this.elements[i][j - 1]);
      }
      return _vector.Vector.create(col);
    }

    // Returns the number of rows/columns the matrix has

  }, {
    key: 'dimensions',
    value: function dimensions() {
      return {
        rows: this.elements.length,
        cols: this.elements[0].length
      };
    }

    // Returns the number of rows in the matrix

  }, {
    key: 'rows',
    value: function rows() {
      return this.elements.length;
    }

    // Returns the number of columns in the matrix

  }, {
    key: 'cols',
    value: function cols() {
      return this.elements[0].length;
    }
  }, {
    key: 'approxEql',
    value: function approxEql(matrix) {
      return this.eql(matrix, _sylvester.Sylvester.approxPrecision);
    }

    // Returns true iff the matrix is equal to the argument. You can supply
    // a vector as the argument, in which case the receiver must be a
    // one-column matrix equal to the vector.

  }, {
    key: 'eql',
    value: function eql(matrix, precision) {
      var M = matrix.elements || matrix;
      if (typeof M[0][0] === 'undefined') {
        M = Matrix.create(M).elements;
      }
      if (this.elements.length !== M.length || this.elements[0].length !== M[0].length) {
        return false;
      }
      var i = this.elements.length;
      var nj = this.elements[0].length;
      var j = void 0;
      while (i--) {
        j = nj;
        while (j--) {
          if (Math.abs(this.elements[i][j] - M[i][j]) > (precision || _sylvester.Sylvester.precision)) {
            return false;
          }
        }
      }
      return true;
    }

    // Returns a copy of the matrix

  }, {
    key: 'dup',
    value: function dup() {
      return Matrix.create(this.elements);
    }

    // Maps the matrix to another matrix (of the same dimensions) according to the given function

  }, {
    key: 'map',
    value: function map(fn) {
      var els = [];
      var i = this.elements.length;
      var nj = this.elements[0].length;
      var j = void 0;
      while (i--) {
        j = nj;
        els[i] = [];
        while (j--) {
          els[i][j] = fn(this.elements[i][j], i + 1, j + 1);
        }
      }
      return Matrix.create(els);
    }

    // Returns true iff the argument has the same dimensions as the matrix

  }, {
    key: 'isSameSizeAs',
    value: function isSameSizeAs(matrix) {
      var M = matrix.elements || matrix;
      if (typeof M[0][0] === 'undefined') {
        M = Matrix.create(M).elements;
      }
      return this.elements.length === M.length && this.elements[0].length === M[0].length;
    }

    // Returns the result of adding the argument to the matrix

  }, {
    key: 'add',
    value: function add(matrix) {
      if (typeof matrix === 'number') {
        return this.map(function (x) {
          return x + matrix;
        });
      }

      var M = matrix.elements || matrix;
      if (typeof M[0][0] === 'undefined') {
        M = Matrix.create(M).elements;
      }
      if (!this.isSameSizeAs(M)) {
        return null;
      }
      return this.map(function (x, i, j) {
        return x + M[i - 1][j - 1];
      });
    }

    // Returns the result of subtracting the argument from the matrix

  }, {
    key: 'subtract',
    value: function subtract(matrix) {
      if (typeof matrix === 'number') {
        return this.map(function (x) {
          return x - matrix;
        });
      }

      var M = matrix.elements || matrix;
      if (typeof M[0][0] === 'undefined') {
        M = Matrix.create(M).elements;
      }
      if (!this.isSameSizeAs(M)) {
        return null;
      }
      return this.map(function (x, i, j) {
        return x - M[i - 1][j - 1];
      });
    }

    // Returns true iff the matrix can multiply the argument from the left

  }, {
    key: 'canMultiplyFromLeft',
    value: function canMultiplyFromLeft(matrix) {
      var M = matrix.elements || matrix;
      if (typeof M[0][0] === 'undefined') {
        M = Matrix.create(M).elements;
      }
      // this.columns should equal matrix.rows
      return this.elements[0].length === M.length;
    }

    // Returns the result of a multiplication-style operation the matrix from the right by the argument.
    // If the argument is a scalar then just operate on all the elements. If the argument is
    // a vector, a vector is returned, which saves you having to remember calling
    // col(1) on the result.

  }, {
    key: 'mulOp',
    value: function mulOp(matrix, op) {
      if (!matrix.elements) {
        return this.map(function (x) {
          return op(x, matrix);
        });
      }

      var returnVector = Boolean(matrix.modulus);
      var M = matrix.elements || matrix;
      if (typeof M[0][0] === 'undefined') {
        M = Matrix.create(M).elements;
      }
      if (!this.canMultiplyFromLeft(M)) {
        return null;
      }
      var e = this.elements;
      var rowThis = void 0;
      var rowElem = void 0;
      var elements = [];
      var sum = void 0;
      var m = e.length;
      var n = M[0].length;
      var o = e[0].length;
      var i = m;
      var j = void 0;
      var k = void 0;

      while (i--) {
        rowElem = [];
        rowThis = e[i];
        j = n;

        while (j--) {
          sum = 0;
          k = o;

          while (k--) {
            sum += op(rowThis[k], M[k][j]);
          }

          rowElem[j] = sum;
        }

        elements[i] = rowElem;
      }

      var output = Matrix.create(elements);
      return returnVector ? output.col(1) : output;
    }

    // Returns the result of dividing the matrix from the right by the argument.
    // If the argument is a scalar then just divide all the elements. If the argument is
    // a vector, a vector is returned, which saves you having to remember calling
    // col(1) on the result.

  }, {
    key: 'div',
    value: function div(matrix) {
      return this.mulOp(matrix, function (x, y) {
        return x / y;
      });
    }

    // Returns the result of multiplying the matrix from the right by the argument.
    // If the argument is a scalar then just multiply all the elements. If the argument is
    // a vector, a vector is returned, which saves you having to remember calling
    // col(1) on the result.

  }, {
    key: 'multiply',
    value: function multiply(matrix) {
      return this.mulOp(matrix, function (x, y) {
        return x * y;
      });
    }
  }, {
    key: 'x',
    value: function x(matrix) {
      return this.multiply(matrix);
    }
  }, {
    key: 'elementMultiply',
    value: function elementMultiply(v) {
      return this.map(function (k, i, j) {
        return v.e(i, j) * k;
      });
    }

    // sum all elements in the matrix

  }, {
    key: 'sum',
    value: function sum() {
      var sum = 0;
      this.map(function (x) {
        // eslint-disable-line array-callback-return
        sum += x;
      });
      return sum;
    }

    // Returns a Vector of each colum averaged.

  }, {
    key: 'mean',
    value: function mean() {
      var dim = this.dimensions();
      var r = [];
      for (var i = 1; i <= dim.cols; i++) {
        r.push(this.col(i).sum() / dim.rows);
      }
      return _vector.Vector.create(r);
    }

    // Returns a Vector of each column's standard deviation

  }, {
    key: 'std',
    value: function std() {
      var dim = this.dimensions();
      var mMean = this.mean();
      var r = [];
      for (var i = 1; i <= dim.cols; i++) {
        var meanDiff = this.col(i).subtract(mMean.e(i));
        meanDiff = meanDiff.multiply(meanDiff);
        r.push(Math.sqrt(meanDiff.sum() / dim.rows));
      }
      return _vector.Vector.create(r);
    }
  }, {
    key: 'column',
    value: function column(n) {
      return this.col(n);
    }

    // element-wise log

  }, {
    key: 'log',
    value: function log() {
      return this.map(function (x) {
        return Math.log(x);
      });
    }

    // Returns a submatrix taken from the matrix
    // Argument order is: start row, start col, nrows, ncols
    // Element selection wraps if the required index is outside the matrix's bounds, so you could
    // use this to perform row/column cycling or copy-augmenting.

  }, {
    key: 'minor',
    value: function minor(a, b, c, d) {
      var elements = [];
      var ni = c;
      var i = void 0;
      var nj = void 0;
      var j = void 0;
      var rows = this.elements.length;
      var cols = this.elements[0].length;
      while (ni--) {
        i = c - ni - 1;
        elements[i] = [];
        nj = d;
        while (nj--) {
          j = d - nj - 1;
          elements[i][j] = this.elements[(a + i - 1) % rows][(b + j - 1) % cols];
        }
      }
      return Matrix.create(elements);
    }

    // Returns the transpose of the matrix

  }, {
    key: 'transpose',
    value: function transpose() {
      var rows = this.elements.length;
      var cols = this.elements[0].length;
      var elements = [];
      var i = cols;
      var j = void 0;
      while (i--) {
        j = rows;
        elements[i] = [];
        while (j--) {
          elements[i][j] = this.elements[j][i];
        }
      }
      return Matrix.create(elements);
    }

    // Returns true iff the matrix is square

  }, {
    key: 'isSquare',
    value: function isSquare() {
      return this.elements.length === this.elements[0].length;
    }

    // Returns the (absolute) largest element of the matrix

  }, {
    key: 'max',
    value: function max() {
      var m = 0;
      var i = this.elements.length;
      var nj = this.elements[0].length;
      var j = void 0;
      while (i--) {
        j = nj;
        while (j--) {
          if (Math.abs(this.elements[i][j]) > Math.abs(m)) {
            m = this.elements[i][j];
          }
        }
      }
      return m;
    }

    // Returns the indeces of the first match found by reading row-by-row from left to right

  }, {
    key: 'indexOf',
    value: function indexOf(x) {
      var ni = this.elements.length;
      var i = void 0;
      var nj = this.elements[0].length;
      var j = void 0;
      for (i = 0; i < ni; i++) {
        for (j = 0; j < nj; j++) {
          if (this.elements[i][j] === x) {
            return {
              i: i + 1,
              j: j + 1
            };
          }
        }
      }
      return null;
    }

    // If the matrix is square, returns the diagonal elements as a vector.
    // Otherwise, returns null.

  }, {
    key: 'diagonal',
    value: function diagonal() {
      if (!this.isSquare) {
        return null;
      }
      var els = [];
      var n = this.elements.length;
      for (var i = 0; i < n; i++) {
        els.push(this.elements[i][i]);
      }
      return _vector.Vector.create(els);
    }

    // Make the matrix upper (right) triangular by Gaussian elimination.
    // This method only adds multiples of rows to other rows. No rows are
    // scaled up or switched, and the determinant is preserved.

  }, {
    key: 'toRightTriangular',
    value: function toRightTriangular() {
      var M = this.dup();
      var els = void 0;
      var n = this.elements.length;
      var i = void 0;
      var j = void 0;
      var np = this.elements[0].length;
      var p = void 0;
      for (i = 0; i < n; i++) {
        if (M.elements[i][i] === 0) {
          for (j = i + 1; j < n; j++) {
            if (M.elements[j][i] !== 0) {
              els = [];
              for (p = 0; p < np; p++) {
                els.push(M.elements[i][p] + M.elements[j][p]);
              }
              M.elements[i] = els;
              break;
            }
          }
        }
        if (M.elements[i][i] !== 0) {
          for (j = i + 1; j < n; j++) {
            var multiplier = M.elements[j][i] / M.elements[i][i];
            els = [];
            for (p = 0; p < np; p++) {
              // Elements with column numbers up to an including the number
              // of the row that we're subtracting can safely be set straight to
              // zero, since that's the point of this routine and it avoids having
              // to loop over and correct rounding errors later
              els.push(p <= i ? 0 : M.elements[j][p] - M.elements[i][p] * multiplier);
            }
            M.elements[j] = els;
          }
        }
      }
      return M;
    }
  }, {
    key: 'toUpperTriangular',
    value: function toUpperTriangular() {
      return this.toRightTriangular();
    }

    // Returns the determinant for square matrices

  }, {
    key: 'determinant',
    value: function determinant() {
      if (!this.isSquare()) {
        return null;
      }
      if (this.cols === 1 && this.rows === 1) {
        return this.row(1);
      }
      if (this.cols === 0 && this.rows === 0) {
        return 1;
      }
      var M = this.toRightTriangular();
      var det = M.elements[0][0];
      var n = M.elements.length;
      for (var i = 1; i < n; i++) {
        det *= M.elements[i][i];
      }
      return det;
    }
  }, {
    key: 'det',
    value: function det() {
      return this.determinant();
    }

    // Returns true iff the matrix is singular

  }, {
    key: 'isSingular',
    value: function isSingular() {
      return this.isSquare() && this.determinant() === 0;
    }

    // Returns the trace for square matrices

  }, {
    key: 'trace',
    value: function trace() {
      if (!this.isSquare()) {
        return null;
      }
      var tr = this.elements[0][0];
      var n = this.elements.length;
      for (var i = 1; i < n; i++) {
        tr += this.elements[i][i];
      }
      return tr;
    }
  }, {
    key: 'tr',
    value: function tr() {
      return this.trace();
    }

    // Returns the rank of the matrix

  }, {
    key: 'rank',
    value: function rank() {
      var M = this.toRightTriangular();
      var rank = 0;
      var i = this.elements.length;
      var nj = this.elements[0].length;
      var j = void 0;
      while (i--) {
        j = nj;
        while (j--) {
          if (Math.abs(M.elements[i][j]) > _sylvester.Sylvester.precision) {
            rank++;
            break;
          }
        }
      }
      return rank;
    }
  }, {
    key: 'rk',
    value: function rk() {
      return this.rank();
    }

    // Returns the result of attaching the given argument to the right-hand side of the matrix

  }, {
    key: 'augment',
    value: function augment(matrix) {
      var M = matrix.elements || matrix;
      if (typeof M[0][0] === 'undefined') {
        M = Matrix.create(M).elements;
      }
      var T = this.dup();
      var cols = T.elements[0].length;
      var i = T.elements.length;
      var nj = M[0].length;
      var j = void 0;
      if (i !== M.length) {
        return null;
      }
      while (i--) {
        j = nj;
        while (j--) {
          T.elements[i][cols + j] = M[i][j];
        }
      }
      return T;
    }

    // Returns the inverse (if one exists) using Gauss-Jordan

  }, {
    key: 'inverse',
    value: function inverse() {
      if (!this.isSquare() || this.isSingular()) {
        return null;
      }
      var n = this.elements.length;
      var i = n;
      var j = void 0;
      var M = this.augment(Matrix.I(n)).toRightTriangular();
      var np = M.elements[0].length;
      var p = void 0;
      var els = void 0;
      var divisor = void 0;

      var inverseElements = [];
      // Matrix is non-singular so there will be no zeros on the diagonal
      // Cycle through rows from last to first

      var newElement = void 0;
      while (i--) {
        // First, normalise diagonal elements to 1
        els = [];
        inverseElements[i] = [];
        divisor = M.elements[i][i];
        for (p = 0; p < np; p++) {
          newElement = M.elements[i][p] / divisor;
          els.push(newElement);
          // Shuffle off the current row of the right hand side into the results
          // array as it will not be modified by later runs through this loop
          if (p >= n) {
            inverseElements[i].push(newElement);
          }
        }
        M.elements[i] = els;
        // Then, subtract this row from those above it to
        // give the identity matrix on the left hand side
        j = i;
        while (j--) {
          els = [];
          for (p = 0; p < np; p++) {
            els.push(M.elements[j][p] - M.elements[i][p] * M.elements[j][i]);
          }
          M.elements[j] = els;
        }
      }
      return Matrix.create(inverseElements);
    }
  }, {
    key: 'inv',
    value: function inv() {
      return this.inverse();
    }

    // Returns the result of rounding all the elements

  }, {
    key: 'round',
    value: function round() {
      return this.map(function (x) {
        return Math.round(x);
      });
    }

    // Returns a copy of the matrix with elements set to the given value if they
    // differ from it by less than Sylvester.precision

  }, {
    key: 'snapTo',
    value: function snapTo(x) {
      return this.map(function (p) {
        return Math.abs(p - x) <= _sylvester.Sylvester.precision ? x : p;
      });
    }

    // Returns a string representation of the matrix

  }, {
    key: 'inspect',
    value: function inspect() {
      var matrixRows = [];
      var n = this.elements.length;
      for (var i = 0; i < n; i++) {
        matrixRows.push(_vector.Vector.create(this.elements[i]).inspect());
      }
      return matrixRows.join('\n');
    }

    // Returns a array representation of the matrix

  }, {
    key: 'toArray',
    value: function toArray() {
      var matrixRows = [];
      var n = this.elements.length;
      for (var i = 0; i < n; i++) {
        matrixRows.push(this.elements[i]);
      }
      return matrixRows;
    }

    // Set the matrix's elements from an array. If the argument passed
    // is a vector, the resulting matrix will be a single column.

  }, {
    key: 'setElements',
    value: function setElements(els) {
      var i = void 0;
      var j = void 0;
      var elements = els.elements || els;
      if (typeof elements[0][0] !== 'undefined') {
        i = elements.length;
        this.elements = [];
        while (i--) {
          j = elements[i].length;
          this.elements[i] = [];
          while (j--) {
            this.elements[i][j] = elements[i][j];
          }
        }
        return this;
      }
      var n = elements.length;
      this.elements = [];
      for (i = 0; i < n; i++) {
        this.elements.push([elements[i]]);
      }
      return this;
    }

    // return the indexes of the columns with the largest value
    // for each row

  }, {
    key: 'maxColumnIndexes',
    value: function maxColumnIndexes() {
      var maxes = [];

      for (var i = 1; i <= this.rows(); i++) {
        var max = null;
        var maxIndex = -1;

        for (var j = 1; j <= this.cols(); j++) {
          if (max === null || this.e(i, j) > max) {
            max = this.e(i, j);
            maxIndex = j;
          }
        }

        maxes.push(maxIndex);
      }

      return _vector.Vector.create(maxes);
    }

    // return the largest values in each row

  }, {
    key: 'maxColumns',
    value: function maxColumns() {
      var maxes = [];

      for (var i = 1; i <= this.rows(); i++) {
        var max = null;

        for (var j = 1; j <= this.cols(); j++) {
          if (max === null || this.e(i, j) > max) {
            max = this.e(i, j);
          }
        }

        maxes.push(max);
      }

      return _vector.Vector.create(maxes);
    }

    // return the indexes of the columns with the smallest values
    // for each row

  }, {
    key: 'minColumnIndexes',
    value: function minColumnIndexes() {
      var mins = [];

      for (var i = 1; i <= this.rows(); i++) {
        var min = null;
        var minIndex = -1;

        for (var j = 1; j <= this.cols(); j++) {
          if (min === null || this.e(i, j) < min) {
            min = this.e(i, j);
            minIndex = j;
          }
        }

        mins.push(minIndex);
      }

      return _vector.Vector.create(mins);
    }

    // return the smallest values in each row

  }, {
    key: 'minColumns',
    value: function minColumns() {
      var mins = [];

      for (var i = 1; i <= this.rows(); i++) {
        var min = null;

        for (var j = 1; j <= this.cols(); j++) {
          if (min === null || this.e(i, j) < min) {
            min = this.e(i, j);
          }
        }

        mins.push(min);
      }

      return _vector.Vector.create(mins);
    }

    // perorm a partial pivot on the matrix. essentially move the largest
    // row below-or-including the pivot and replace the pivot's row with it.
    // a pivot matrix is returned so multiplication can perform the transform.

  }, {
    key: 'partialPivot',
    value: function partialPivot(k, j, P, A) {
      var maxIndex = 0;
      var maxValue = 0;

      for (var i = k; i <= A.rows(); i++) {
        if (Math.abs(A.e(i, j)) > maxValue) {
          maxValue = Math.abs(A.e(k, j));
          maxIndex = i;
        }
      }

      if (maxIndex !== k) {
        var tmp = A.elements[k - 1];
        A.elements[k - 1] = A.elements[maxIndex - 1];
        A.elements[maxIndex - 1] = tmp;

        P.elements[k - 1][k - 1] = 0;
        P.elements[k - 1][maxIndex - 1] = 1;
        P.elements[maxIndex - 1][maxIndex - 1] = 0;
        P.elements[maxIndex - 1][k - 1] = 1;
      }

      return P;
    }

    // solve lower-triangular matrix * x = b via forward substitution

  }, {
    key: 'forwardSubstitute',
    value: function forwardSubstitute(b) {
      var xa = [];

      for (var i = 1; i <= this.rows(); i++) {
        var w = 0;

        for (var j = 1; j < i; j++) {
          w += this.e(i, j) * xa[j - 1];
        }

        xa.push((b.e(i) - w) / this.e(i, i));
      }

      return _vector.Vector.create(xa);
    }

    // solve an upper-triangular matrix * x = b via back substitution

  }, {
    key: 'backSubstitute',
    value: function backSubstitute(b) {
      var xa = [];

      for (var i = this.rows(); i > 0; i--) {
        var w = 0;

        for (var j = this.cols(); j > i; j--) {
          w += this.e(i, j) * xa[this.rows() - j];
        }

        xa.push((b.e(i) - w) / this.e(i, i));
      }

      return _vector.Vector.create(xa.reverse());
    }
  }, {
    key: 'svdJs',
    value: function svdJs() {
      var A = this;
      var V = Matrix.I(A.rows());
      var S = A.transpose();
      var U = Matrix.I(A.cols());
      var err = Number.MAX_VALUE;
      var i = 0;
      var maxLoop = 100;

      while (err > 2.2737e-13 && i < maxLoop) {
        var qr = S.transpose().qrJs();
        S = qr.R;
        V = V.x(qr.Q);
        qr = S.transpose().qrJs();
        U = U.x(qr.Q);
        S = qr.R;

        var e = S.triu(1).unroll().norm();
        var f = S.diagonal().norm();

        if (f === 0) {
          f = 1;
        }

        err = e / f;

        i++;
      }

      var ss = S.diagonal();
      var s = [];

      for (var _i2 = 1; _i2 <= ss.cols(); _i2++) {
        var ssn = ss.e(_i2);
        s.push(Math.abs(ssn));

        if (ssn < 0) {
          for (var j = 0; j < U.rows(); j++) {
            V.elements[j][_i2 - 1] = -V.elements[j][_i2 - 1];
          }
        }
      }

      return {
        U: U,
        S: _vector.Vector.create(s).toDiagonalMatrix(),
        V: V
      };
    }

    // singular value decomposition using LAPACK

  }, {
    key: 'svdPack',
    value: function svdPack() {
      var result = lapack.sgesvd('A', 'A', this.elements);

      return {
        U: Matrix.create(result.U),
        S: Matrix.create(result.S).column(1).toDiagonalMatrix(),
        V: Matrix.create(result.VT).transpose()
      };
    }

    // QR decomposition in pure javascript

  }, {
    key: 'qrJs',
    value: function qrJs() {
      var m = this.rows();
      var n = this.cols();
      var Q = Matrix.I(m);
      var A = this;

      for (var k = 1; k < Math.min(m, n); k++) {
        var ak = A.slice(k, 0, k, k).col(1);
        var oneZero = [1];

        while (oneZero.length <= m - k) {
          oneZero.push(0);
        }

        oneZero = _vector.Vector.create(oneZero);
        var vk = ak.add(oneZero.x(ak.norm() * sign(ak.e(1))));
        var Vk = Matrix.create(vk);
        var Hk = Matrix.I(m - k + 1).subtract(Vk.x(2).x(Vk.transpose()).div(Vk.transpose().x(Vk).e(1, 1)));
        var Qk = identSize(Hk, m, n, k);
        A = Qk.x(A);
        // slow way to compute Q
        Q = Q.x(Qk);
      }

      return {
        Q: Q,
        R: A
      };
    }

    // QR decomposition using LAPACK

  }, {
    key: 'qrPack',
    value: function qrPack() {
      var qr = lapack.qr(this.elements);

      return {
        Q: Matrix.create(qr.Q),
        R: Matrix.create(qr.R)
      };
    }

    // LU factorization from LAPACK

  }, {
    key: 'luPack',
    value: function luPack() {
      var lu = lapack.lu(this.elements);
      return {
        L: Matrix.create(lu.L),
        U: Matrix.create(lu.U),
        P: Matrix.create(lu.P)
        // don't pass back IPIV
      };
    }

    // pure Javascript LU factorization

  }, {
    key: 'luJs',
    value: function luJs() {
      var A = this.dup();
      var L = Matrix.I(A.rows());
      var P = Matrix.I(A.rows());
      var U = Matrix.Zeros(A.rows(), A.cols());
      var p = 1;

      for (var k = 1; k <= Math.min(A.cols(), A.rows()); k++) {
        P = A.partialPivot(k, p, P, A, L);

        for (var i = k + 1; i <= A.rows(); i++) {
          var l = A.e(i, p) / A.e(k, p);
          L.elements[i - 1][k - 1] = l;

          for (var j = k + 1; j <= A.cols(); j++) {
            A.elements[i - 1][j - 1] -= A.e(k, j) * l;
          }
        }

        for (var _j = k; _j <= A.cols(); _j++) {
          U.elements[k - 1][_j - 1] = A.e(k, _j);
        }

        if (p < A.cols()) {
          p++;
        }
      }

      return {
        L: L,
        U: U,
        P: P
      };
    }

    // Constructor function

  }], [{
    key: 'create',
    value: function create(aElements) {
      var M = new Matrix().setElements(aElements);
      return M;
    }

    // Identity matrix of size n

  }, {
    key: 'I',
    value: function I(n) {
      var els = [];
      var i = n;
      var j = void 0;
      while (i--) {
        j = n;
        els[i] = [];
        while (j--) {
          els[i][j] = i === j ? 1 : 0;
        }
      }
      return Matrix.create(els);
    }
  }, {
    key: 'loadFile',
    value: function loadFile(file) {
      var contents = fs.readFileSync(file, 'utf-8');
      var matrix = [];

      var rowArray = contents.split('\n');
      for (var i = 0; i < rowArray.length; i++) {
        var d = rowArray[i].split(',');
        if (d.length > 1) {
          matrix.push(d);
        }
      }

      var M = new Matrix();
      return M.setElements(matrix);
    }

    // Diagonal matrix - all off-diagonal elements are zero

  }, {
    key: 'Diagonal',
    value: function Diagonal(elements) {
      var i = elements.length;
      var M = Matrix.I(i);
      while (i--) {
        M.elements[i][i] = elements[i];
      }
      return M;
    }

    // Rotation matrix about some axis. If no axis is
    // supplied, assume we're after a 2D transform

  }, {
    key: 'Rotation',
    value: function Rotation(theta, a) {
      if (!a) {
        return Matrix.create([[Math.cos(theta), -Math.sin(theta)], [Math.sin(theta), Math.cos(theta)]]);
      }
      var axis = a.dup();
      if (axis.elements.length !== 3) {
        return null;
      }
      var mod = axis.modulus();
      var x = axis.elements[0] / mod;
      var y = axis.elements[1] / mod;
      var z = axis.elements[2] / mod;

      var s = Math.sin(theta);
      // Formula derived here: http://www.gamedev.net/reference/articles/article1199.asp
      // That proof rotates the co-ordinate system so theta
      // becomes -theta and sin becomes -sin here.

      var c = Math.cos(theta);
      var t = 1 - c;
      return Matrix.create([[t * x * x + c, t * x * y - s * z, t * x * z + s * y], [t * x * y + s * z, t * y * y + c, t * y * z - s * x], [t * x * z - s * y, t * y * z + s * x, t * z * z + c]]);
    }

    // Special case rotations

  }, {
    key: 'RotationX',
    value: function RotationX(t) {
      var c = Math.cos(t);
      var s = Math.sin(t);
      return Matrix.create([[1, 0, 0], [0, c, -s], [0, s, c]]);
    }
  }, {
    key: 'RotationY',
    value: function RotationY(t) {
      var c = Math.cos(t);
      var s = Math.sin(t);
      return Matrix.create([[c, 0, s], [0, 1, 0], [-s, 0, c]]);
    }
  }, {
    key: 'RotationZ',
    value: function RotationZ(t) {
      var c = Math.cos(t);
      var s = Math.sin(t);
      return Matrix.create([[c, -s, 0], [s, c, 0], [0, 0, 1]]);
    }

    // Random matrix of n rows, m columns

  }, {
    key: 'Random',
    value: function Random(n, m) {
      if (arguments.length === 1) {
        m = n;
      }
      return Matrix.Zero(n, m).map(function () {
        return Math.random();
      });
    }
  }, {
    key: 'Fill',
    value: function Fill(n, m, v) {
      if (arguments.length === 2) {
        v = m;
        m = n;
      }

      var els = [];
      var i = n;
      var j = void 0;

      while (i--) {
        j = m;
        els[i] = [];

        while (j--) {
          els[i][j] = v;
        }
      }

      return Matrix.create(els);
    }

    // Matrix filled with zeros

  }, {
    key: 'Zero',
    value: function Zero(n, m) {
      return Matrix.Fill(n, m, 0);
    }

    // Matrix filled with zeros

  }, {
    key: 'Zeros',
    value: function Zeros(n, m) {
      return Matrix.Zero(n, m);
    }

    // Matrix filled with ones

  }, {
    key: 'One',
    value: function One(n, m) {
      return Matrix.Fill(n, m, 1);
    }

    // Matrix filled with ones

  }, {
    key: 'Ones',
    value: function Ones(n, m) {
      return Matrix.One(n, m);
    }
  }]);

  return Matrix;
}();

// if node-lapack is installed use the fast, native fortran routines


if (lapack) {
  Matrix.prototype.svd = Matrix.prototype.svdPack;
  Matrix.prototype.qr = Matrix.prototype.qrPack;
  Matrix.prototype.lu = Matrix.prototype.luPack;
} else {
  // otherwise use the slower pure Javascript versions
  Matrix.prototype.svd = Matrix.prototype.svdJs;
  Matrix.prototype.qr = Matrix.prototype.qrJs;
  Matrix.prototype.lu = Matrix.prototype.luJs;
}
},{"./sylvester":9,"./vector":10,"fs":1,"lapack":1}],8:[function(require,module,exports){
'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.Plane = undefined;

var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();

var _line = require('./line');

var _matrix = require('./matrix');

var _sylvester = require('./sylvester');

var _vector = require('./vector');

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

var Plane = exports.Plane = function () {
  function Plane() {
    _classCallCheck(this, Plane);
  }

  _createClass(Plane, [{
    key: 'eql',

    // Returns true iff the plane occupies the same space as the argument
    value: function eql(plane) {
      return this.contains(plane.anchor) && this.isParallelTo(plane);
    }

    // Returns a copy of the plane

  }, {
    key: 'dup',
    value: function dup() {
      return Plane.create(this.anchor, this.normal);
    }

    // Returns the result of translating the plane by the given vector

  }, {
    key: 'translate',
    value: function translate(vector) {
      var V = vector.elements || vector;
      return Plane.create([this.anchor.elements[0] + V[0], this.anchor.elements[1] + V[1], this.anchor.elements[2] + (V[2] || 0)], this.normal);
    }

    // Returns true iff the plane is parallel to the argument. Will return true
    // if the planes are equal, or if you give a line and it lies in the plane.

  }, {
    key: 'isParallelTo',
    value: function isParallelTo(obj) {
      var theta = void 0;
      if (obj.normal) {
        // obj is a plane
        theta = this.normal.angleFrom(obj.normal);
        return Math.abs(theta) <= _sylvester.Sylvester.precision || Math.abs(Math.PI - theta) <= _sylvester.Sylvester.precision;
      } else if (obj.direction) {
        // obj is a line
        return this.normal.isPerpendicularTo(obj.direction);
      }
      return null;
    }

    // Returns true iff the receiver is perpendicular to the argument

  }, {
    key: 'isPerpendicularTo',
    value: function isPerpendicularTo(plane) {
      var theta = this.normal.angleFrom(plane.normal);
      return Math.abs(Math.PI / 2 - theta) <= _sylvester.Sylvester.precision;
    }

    // Returns the plane's distance from the given object (point, line or plane)

  }, {
    key: 'distanceFrom',
    value: function distanceFrom(obj) {
      if (this.intersects(obj) || this.contains(obj)) {
        return 0;
      }
      if (obj.anchor) {
        // obj is a plane or line
        var _A = this.anchor.elements;
        var B = obj.anchor.elements;
        var _N = this.normal.elements;
        return Math.abs((_A[0] - B[0]) * _N[0] + (_A[1] - B[1]) * _N[1] + (_A[2] - B[2]) * _N[2]);
      }

      // obj is a point
      var P = obj.elements || obj;
      var A = this.anchor.elements;
      var N = this.normal.elements;
      return Math.abs((A[0] - P[0]) * N[0] + (A[1] - P[1]) * N[1] + (A[2] - (P[2] || 0)) * N[2]);
    }

    // Returns true iff the plane contains the given point or line

  }, {
    key: 'contains',
    value: function contains(obj) {
      if (obj.normal) {
        return null;
      }
      if (obj.direction) {
        return this.contains(obj.anchor) && this.contains(obj.anchor.add(obj.direction));
      }

      var P = obj.elements || obj;
      var A = this.anchor.elements;
      var N = this.normal.elements;
      var diff = Math.abs(N[0] * (A[0] - P[0]) + N[1] * (A[1] - P[1]) + N[2] * (A[2] - (P[2] || 0)));
      return diff <= _sylvester.Sylvester.precision;
    }

    // Returns true iff the plane has a unique point/line of intersection with the argument

  }, {
    key: 'intersects',
    value: function intersects(obj) {
      if (typeof obj.direction === 'undefined' && typeof obj.normal === 'undefined') {
        return null;
      }
      return !this.isParallelTo(obj);
    }

    // Returns the unique intersection with the argument, if one exists. The result
    // will be a vector if a line is supplied, and a line if a plane is supplied.

  }, {
    key: 'intersectionWith',
    value: function intersectionWith(obj) {
      if (!this.intersects(obj)) {
        return null;
      }

      if (obj.direction) {
        // obj is a line
        var A = obj.anchor.elements;

        var D = obj.direction.elements;
        var P = this.anchor.elements;
        var N = this.normal.elements;
        var multiplier = (N[0] * (P[0] - A[0]) + N[1] * (P[1] - A[1]) + N[2] * (P[2] - A[2])) / (N[0] * D[0] + N[1] * D[1] + N[2] * D[2]);

        return _vector.Vector.create([A[0] + D[0] * multiplier, A[1] + D[1] * multiplier, A[2] + D[2] * multiplier]);
      }

      if (obj.normal) {
        // obj is a plane
        var direction = this.normal.cross(obj.normal).toUnitVector();

        // To find an anchor point, we find one co-ordinate that has a value
        // of zero somewhere on the intersection, and remember which one we picked
        var _N2 = this.normal.elements;

        var _A2 = this.anchor.elements;
        var O = obj.normal.elements;
        var B = obj.anchor.elements;
        var solver = _matrix.Matrix.Zero(2, 2);
        var i = 0;
        while (solver.isSingular()) {
          i++;
          solver = _matrix.Matrix.create([[_N2[i % 3], _N2[(i + 1) % 3]], [O[i % 3], O[(i + 1) % 3]]]);
        }
        // Then we solve the simultaneous equations in the remaining dimensions
        var inverse = solver.inverse().elements;
        var x = _N2[0] * _A2[0] + _N2[1] * _A2[1] + _N2[2] * _A2[2];
        var y = O[0] * B[0] + O[1] * B[1] + O[2] * B[2];
        var intersection = [inverse[0][0] * x + inverse[0][1] * y, inverse[1][0] * x + inverse[1][1] * y];
        var anchor = [];
        for (var j = 1; j <= 3; j++) {
          // This formula picks the right element from intersection by
          // cycling depending on which element we set to zero above
          anchor.push(i === j ? 0 : intersection[(j + (5 - i) % 3) % 3]);
        }
        return _line.Line.create(anchor, direction);
      }

      return null; // todo(connor4312): is this a case that needs to be handled?
    }

    // Returns the point in the plane closest to the given point

  }, {
    key: 'pointClosestTo',
    value: function pointClosestTo(point) {
      var P = point.elements || point;
      var A = this.anchor.elements;
      var N = this.normal.elements;
      var dot = (A[0] - P[0]) * N[0] + (A[1] - P[1]) * N[1] + (A[2] - (P[2] || 0)) * N[2];
      return _vector.Vector.create([P[0] + N[0] * dot, P[1] + N[1] * dot, (P[2] || 0) + N[2] * dot]);
    }

    // Returns a copy of the plane, rotated by t radians about the given line
    // See notes on Line#rotate.

  }, {
    key: 'rotate',
    value: function rotate(t, line) {
      var R = t.determinant ? t.elements : _matrix.Matrix.Rotation(t, line.direction).elements;
      var C = line.pointClosestTo(this.anchor).elements;
      var A = this.anchor.elements;
      var N = this.normal.elements;
      var C1 = C[0];
      var C2 = C[1];
      var C3 = C[2];
      var A1 = A[0];
      var A2 = A[1];
      var A3 = A[2];
      var x = A1 - C1;
      var y = A2 - C2;
      var z = A3 - C3;
      return Plane.create([C1 + R[0][0] * x + R[0][1] * y + R[0][2] * z, C2 + R[1][0] * x + R[1][1] * y + R[1][2] * z, C3 + R[2][0] * x + R[2][1] * y + R[2][2] * z], [R[0][0] * N[0] + R[0][1] * N[1] + R[0][2] * N[2], R[1][0] * N[0] + R[1][1] * N[1] + R[1][2] * N[2], R[2][0] * N[0] + R[2][1] * N[1] + R[2][2] * N[2]]);
    }

    // Returns the reflection of the plane in the given point, line or plane.

  }, {
    key: 'reflectionIn',
    value: function reflectionIn(obj) {
      if (obj.normal) {
        // obj is a plane
        var A = this.anchor.elements;

        var N = this.normal.elements;
        var A1 = A[0];
        var A2 = A[1];
        var A3 = A[2];
        var N1 = N[0];
        var N2 = N[1];
        var N3 = N[2];
        var newA = this.anchor.reflectionIn(obj).elements;

        // Add the plane's normal to its anchor, then mirror that in the other plane
        var AN1 = A1 + N1;

        var AN2 = A2 + N2;
        var AN3 = A3 + N3;
        var Q = obj.pointClosestTo([AN1, AN2, AN3]).elements;
        var newN = [Q[0] + (Q[0] - AN1) - newA[0], Q[1] + (Q[1] - AN2) - newA[1], Q[2] + (Q[2] - AN3) - newA[2]];
        return Plane.create(newA, newN);
      }
      if (obj.direction) {
        // obj is a line
        return this.rotate(Math.PI, obj);
      }

      // obj is a point
      var P = obj.elements || obj;
      return Plane.create(this.anchor.reflectionIn([P[0], P[1], P[2] || 0]), this.normal);
    }

    // Sets the anchor point and normal to the plane. If three arguments are specified,
    // the normal is calculated by assuming the three points should lie in the same plane.
    // If only two are sepcified, the second is taken to be the normal. Normal vector is
    // normalised before storage.

  }, {
    key: 'setVectors',
    value: function setVectors(anchor, v1, v2) {
      anchor = _vector.Vector.create(anchor);
      anchor = anchor.to3D();
      if (anchor === null) {
        return null;
      }
      v1 = _vector.Vector.create(v1);
      v1 = v1.to3D();
      if (v1 === null) {
        return null;
      }
      if (typeof v2 === 'undefined') {
        v2 = null;
      } else {
        v2 = _vector.Vector.create(v2);
        v2 = v2.to3D();
        if (v2 === null) {
          return null;
        }
      }
      var A1 = anchor.elements[0];
      var A2 = anchor.elements[1];
      var A3 = anchor.elements[2];
      var v11 = v1.elements[0];
      var v12 = v1.elements[1];
      var v13 = v1.elements[2];
      var normal = void 0;
      var mod = void 0;
      if (v2 === null) {
        mod = Math.sqrt(v11 * v11 + v12 * v12 + v13 * v13);
        if (mod === 0) {
          return null;
        }
        normal = _vector.Vector.create([v1.elements[0] / mod, v1.elements[1] / mod, v1.elements[2] / mod]);
      } else {
        var v21 = v2.elements[0];
        var v22 = v2.elements[1];
        var v23 = v2.elements[2];
        normal = _vector.Vector.create([(v12 - A2) * (v23 - A3) - (v13 - A3) * (v22 - A2), (v13 - A3) * (v21 - A1) - (v11 - A1) * (v23 - A3), (v11 - A1) * (v22 - A2) - (v12 - A2) * (v21 - A1)]);
        mod = normal.modulus();
        if (mod === 0) {
          return null;
        }
        normal = _vector.Vector.create([normal.elements[0] / mod, normal.elements[1] / mod, normal.elements[2] / mod]);
      }

      this.anchor = anchor;
      this.normal = normal;
      return this;
    }

    // Constructor function

  }], [{
    key: 'create',
    value: function create(anchor, v1, v2) {
      var P = new Plane();
      return P.setVectors(anchor, v1, v2);
    }

    // Returns the plane containing the given points (can be arrays as
    // well as vectors). If the points are not coplanar, returns null.

  }, {
    key: 'fromPoints',
    value: function fromPoints(points) {
      var np = points.length;
      var list = [];
      var i = void 0;
      var P = void 0;
      var n = void 0;
      var N = void 0;
      var A = void 0;
      var B = void 0;
      var C = void 0;
      var theta = void 0;
      var prevN = void 0;
      var totalN = _vector.Vector.Zero(3);
      for (i = 0; i < np; i++) {
        P = _vector.Vector.create(points[i]).to3D();
        if (P === null) {
          return null;
        }
        list.push(P);
        n = list.length;
        if (n > 2) {
          // Compute plane normal for the latest three points
          A = list[n - 1].elements;
          B = list[n - 2].elements;
          C = list[n - 3].elements;
          N = _vector.Vector.create([(A[1] - B[1]) * (C[2] - B[2]) - (A[2] - B[2]) * (C[1] - B[1]), (A[2] - B[2]) * (C[0] - B[0]) - (A[0] - B[0]) * (C[2] - B[2]), (A[0] - B[0]) * (C[1] - B[1]) - (A[1] - B[1]) * (C[0] - B[0])]).toUnitVector();

          if (n > 3) {
            // If the latest normal is not (anti)parallel to the previous one, we've strayed off the plane.
            // This might be a slightly long-winded way of doing things, but we need the sum of all the normals
            // to find which way the plane normal should point so that the points form an anticlockwise list.
            theta = N.angleFrom(prevN);
            if (theta !== null) {
              if (!(Math.abs(theta) <= _sylvester.Sylvester.precision || Math.abs(theta - Math.PI) <= _sylvester.Sylvester.precision)) {
                return null;
              }
            }
          }
          totalN = totalN.add(N);
          prevN = N;
        }
      }
      // We need to add in the normals at the start and end points, which the above misses out
      A = list[1].elements;
      B = list[0].elements;
      C = list[n - 1].elements;
      var D = list[n - 2].elements;
      totalN = totalN.add(_vector.Vector.create([(A[1] - B[1]) * (C[2] - B[2]) - (A[2] - B[2]) * (C[1] - B[1]), (A[2] - B[2]) * (C[0] - B[0]) - (A[0] - B[0]) * (C[2] - B[2]), (A[0] - B[0]) * (C[1] - B[1]) - (A[1] - B[1]) * (C[0] - B[0])]).toUnitVector()).add(_vector.Vector.create([(B[1] - C[1]) * (D[2] - C[2]) - (B[2] - C[2]) * (D[1] - C[1]), (B[2] - C[2]) * (D[0] - C[0]) - (B[0] - C[0]) * (D[2] - C[2]), (B[0] - C[0]) * (D[1] - C[1]) - (B[1] - C[1]) * (D[0] - C[0])]).toUnitVector());
      return Plane.create(list[0], totalN);
    }
  }]);

  return Plane;
}();

// X-Y-Z planes


Plane.XY = Plane.YX = Plane.create(_vector.Vector.Zero(3), _vector.Vector.k);
Plane.YZ = Plane.ZY = Plane.create(_vector.Vector.Zero(3), _vector.Vector.i);
Plane.ZX = Plane.XZ = Plane.create(_vector.Vector.Zero(3), _vector.Vector.j);
},{"./line":6,"./matrix":7,"./sylvester":9,"./vector":10}],9:[function(require,module,exports){
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

function _possibleConstructorReturn(self, call) { if (!self) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return call && (typeof call === "object" || typeof call === "function") ? call : self; }

function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function, not " + typeof superClass); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : subClass.__proto__ = superClass; }

/**
 * Default Sylvester configurations.
 * @type {Object}
 */
var Sylvester = exports.Sylvester = {
  precision: 1e-6,
  approxPrecision: 1e-5
};

/**
 * A DimensionalityMismatchError is thrown when an operation is run on two
 * units which should share a certain dimensional relationship, but fail it.
 */

var DimensionalityMismatchError = exports.DimensionalityMismatchError = function (_Error) {
  _inherits(DimensionalityMismatchError, _Error);

  function DimensionalityMismatchError() {
    _classCallCheck(this, DimensionalityMismatchError);

    return _possibleConstructorReturn(this, (DimensionalityMismatchError.__proto__ || Object.getPrototypeOf(DimensionalityMismatchError)).apply(this, arguments));
  }

  return DimensionalityMismatchError;
}(Error);
},{}],10:[function(require,module,exports){
'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.Vector = undefined;

var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();

var _sylvester = require('./sylvester');

var _matrix = require('./matrix');

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

/**
 * The Vector class is designed to model vectors in any number of dimensions.
 * All the elements of a vector must be real numbers. Depending on what you’re
 * using them for, it can be helpful to think of a vector either as a point
 * in n-dimensional space, or as a line connecting
 * the origin to that same point.
 */
var Vector = exports.Vector = function () {

  /**
   * Creates a new vector, initializing it with the provided elements.
   * @param  {Number[]} elements
   */
  function Vector(elements) {
    _classCallCheck(this, Vector);

    this.elements = elements;
  }

  /**
   * Returns the magnitude (also: euclidean norm, magnitude) of the vector.
   *
   * $example Vector.magnitude
   * @see https://en.wikipedia.org/wiki/Euclidean_distance
   * @return {Number}
   */


  _createClass(Vector, [{
    key: 'magnitude',
    value: function magnitude() {
      var sum = 0;
      for (var i = 0; i < this.elements.length; i++) {
        sum += this.elements[i] * this.elements[i];
      }

      return Math.sqrt(sum);
    }

    /**
     * Returns the `ith` element if the vector. Returns null if `i` is out
     * of bounds, indexing starts from 1.
     *
     * $example Vector.e
     * @param  {Number} i
     * @return {Number}
     */

  }, {
    key: 'e',
    value: function e(i) {
      return i < 1 || i > this.elements.length ? null : this.elements[i - 1];
    }

    /**
     * Returns the number of rows and columns the vector has.
     *
     * $example Vector.dimensions
     * @return {IDimensions} the "rows" will always equal zero
     */

  }, {
    key: 'dimensions',
    value: function dimensions() {
      return {
        rows: 1,
        cols: this.elements.length
      };
    }

    /**
     * Returns the number of rows the vector has.
     *
     * $example Vector.rows
     * @return {Number} always `1`
     */

  }, {
    key: 'rows',
    value: function rows() {
      return 1;
    }

    /**
     * Returns the number of columns the vector has.
     *
     * $example Vector.cols
     * @return {Number}
     */

  }, {
    key: 'cols',
    value: function cols() {
      return this.elements.length;
    }

    /**
     * Returns if the Vector is equal to the input vector.
     * $example Vector.eql
     * @param  {Vector} vector
     * @return {Boolean}
     */

  }, {
    key: 'eql',
    value: function eql(vector) {
      var n = this.elements.length;
      var V = vector.elements || vector;
      if (n !== V.length) {
        return false;
      }
      while (n--) {
        if (Math.abs(this.elements[n] - V[n]) > _sylvester.Sylvester.precision) {
          return false;
        }
      }
      return true;
    }

    /**
     * Returns a new function created by calling the iterator on all values of this vector.
     * @param  {Function} fn
     * @return {Vector}
     */

  }, {
    key: 'map',
    value: function map(fn) {
      var n = this.elements.length;
      var elements = new Array(n);
      for (var i = 0; i < n; i++) {
        elements[i] = fn(this.elements[i], i + 1);
      }

      return new Vector(elements);
    }

    /**
     * Iterates through the elements of the vector
     * @param {Function} fn called with the `(element, index)`
     */

  }, {
    key: 'each',
    value: function each(fn) {
      var n = this.elements.length;
      for (var i = 0; i < n; i++) {
        fn(this.elements[i], i + 1);
      }
    }

    /**
     * Returns a new vector created by normalizing this one to a have a
     * magnitude of `1`. If the vector is the zero vector, it will not be modified.
     *
     * $example Vector.toUnitVector
     * @return {Vector}
     */

  }, {
    key: 'toUnitVector',
    value: function toUnitVector() {
      var r = this.modulus();
      if (r === 0) {
        return this.dup();
      }

      return this.map(function (x) {
        return x / r;
      });
    }

    /**
     * Returns the angle between this vector the argument in radians. If the
     * vectors are mirrored across their axes this will return `NaN`.
     * $example Vector.angleFrom
     * @throws {DimensionalityMismatchError} If a vector is passed in with
     *     different dimensions
     * @param  {Vector} vector
     * @return {Number}
     */

  }, {
    key: 'angleFrom',
    value: function angleFrom(vector) {
      var V = vector.elements || vector;
      var n = this.elements.length;
      if (n !== V.length) {
        throw new _sylvester.DimensionalityMismatchError('Cannot compute the angle between vectors with different dimensionality');
      }

      // Work things out in parallel to save time
      var dot = 0;
      var mod1 = 0;
      var mod2 = 0;
      this.each(function (x, i) {
        dot += x * V[i - 1];
        mod1 += x * x;
        mod2 += V[i - 1] * V[i - 1];
      });
      mod1 = Math.sqrt(mod1);
      mod2 = Math.sqrt(mod2);
      if (mod1 * mod2 === 0) {
        return NaN;
      }

      var theta = dot / (mod1 * mod2);
      if (theta < -1) {
        theta = -1;
      }
      if (theta > 1) {
        theta = 1;
      }
      return Math.acos(theta);
    }

    /**
     * Returns whether the vectors are parallel to each other.
     * $example Vector.isParallelTo
     * @return {Boolean}
     */

  }, {
    key: 'isParallelTo',
    value: function isParallelTo(vector) {
      var angle = this.angleFrom(vector);
      return angle === null ? false : angle <= _sylvester.Sylvester.precision;
    }

    /**
     * Returns whether the vectors are antiparallel to each other.
     * $example Vector.isAntiparallelTo
     * @return {Boolean}
     */

  }, {
    key: 'isAntiparallelTo',
    value: function isAntiparallelTo(vector) {
      var angle = this.angleFrom(vector);
      return angle === null ? false : Math.abs(angle - Math.PI) <= _sylvester.Sylvester.precision;
    }

    /**
     * Returns whether the vectors are perpendicular to each other.
     * $example Vector.isPerpendicularTo
     * @return {Boolean}
     */

  }, {
    key: 'isPerpendicularTo',
    value: function isPerpendicularTo(vector) {
      return Math.abs(this.dot(vector)) <= _sylvester.Sylvester.precision;
    }
  }, {
    key: '_runBinaryOp',
    value: function _runBinaryOp(value, operator) {
      if (typeof value === 'number') {
        return this.map(function (v) {
          return operator(v, value);
        });
      }

      var values = value.elements || value;
      if (this.elements.length !== values.length) {
        throw new _sylvester.DimensionalityMismatchError('Cannot add vectors with different dimensions.');
      }

      return this.map(function (x, i) {
        return operator(x, values[i - 1]);
      });
    }

    /**
     * When the input is a constant, this returns the result of adding it to
     * all cevtor elements. When it's a vector, the vectors will be added.
     * $example Vector.add
     * @throws {DimensionalityMismatchError} If a vector is passed in with
     *     different dimensions
     * @param {Number|Number[]|Vector} value
     * @return {Vector}
     */

  }, {
    key: 'add',
    value: function add(value) {
      return this._runBinaryOp(value, function (a, b) {
        return a + b;
      });
    }

    /**
     * When the input is a constant, this returns the result of subtracting it
     * from all vector elements. When it's a vector, the vectors will be subtracted.
     * $example Vector.subtract
     * @throws {DimensionalityMismatchError} If a vector is passed in with
     *     different dimensions
     * @param {Number|Number[]|Vector} value
     * @return {Vector}
     */

  }, {
    key: 'subtract',
    value: function subtract(value) {
      return this._runBinaryOp(value, function (a, b) {
        return a - b;
      });
    }

    /**
     * When the input is a constant, this returns the result of multiplying it
     * with all vector elements. When it's a vector, the vectors will be
     * element-wise multiplied.
     * $example Vector.multiply
     * @throws {DimensionalityMismatchError} If a vector is passed in with
     *     different dimensions
     * @param {Number|Number[]|Vector} value
     * @return {Vector}
     */

  }, {
    key: 'multiply',
    value: function multiply(value) {
      return this._runBinaryOp(value, function (a, b) {
        return a * b;
      });
    }

    /**
     * Returns the sum of all elements in the Vector.
     * $example Vector.sum
     * @return {Number}
     */

  }, {
    key: 'sum',
    value: function sum() {
      var sum = 0;
      this.each(function (x) {
        sum += x;
      });
      return sum;
    }

    /**
     * Returns a new vector with the first `n` elements removed from the beginning.
     * $example Vector.chomp
     * @param  {Number} n
     * @return {Vector}
     */

  }, {
    key: 'chomp',
    value: function chomp(n) {
      var elements = [];
      for (var i = n; i < this.elements.length; i++) {
        elements.push(this.elements[i]);
      }

      return Vector.create(elements);
    }

    /**
     * Returns a new vector consisting only of the first `n` elements.
     * $example Vector.chomp
     * @param  {Number} n
     * @return {Vector}
     */

  }, {
    key: 'top',
    value: function top(n) {
      var elements = [];
      for (var i = 0; i < n; i++) {
        elements.push(this.elements[i]);
      }

      return Vector.create(elements);
    }

    /**
     * Returns a new vector with the provided `elements` concatenated on the end.
     * $example Vector.augment
     * @param  {Number[]|Vector} elements
     * @return {Vector}
     */

  }, {
    key: 'augment',
    value: function augment(elements) {
      return Vector.create(this.elements.concat(elements.elements || elements));
    }

    /**
     * @alias Vector#multiply
     */

  }, {
    key: 'x',
    value: function x(k) {
      return this.multiply(k);
    }
  }, {
    key: 'log',
    value: function log() {
      return Vector.log(this);
    }

    /**
     * Returns the product of all elements in the vector.
     * $example Vector.product
     * @return {Number}
     */

  }, {
    key: 'product',
    value: function product() {
      var p = 1;
      this.each(function (v) {
        p *= v;
      });

      return p;
    }

    /**
     * Returns the scalar (dot) product of the vector with the argument.
     *
     * $example Vector.dot
     * @see https://en.wikipedia.org/wiki/Scalar_product
     * @throws {DimensionalityMismatchError} If a vector is passed in with
     *     different dimensions
     * @param  {Vector|Number[]} vector
     * @return {Number}
     */

  }, {
    key: 'dot',
    value: function dot(vector) {
      var V = vector.elements || vector;
      var n = this.elements.length;
      if (n !== V.length) {
        throw new _sylvester.DimensionalityMismatchError('Cannot compute the dot product of vectors with different dimensionality');
      }

      var product = 0;
      while (n--) {
        product += this.elements[n] * V[n];
      }
      return product;
    }

    // Returns the vector product of the vector with the argument
    // Both vectors must have dimensionality 3

  }, {
    key: 'cross',
    value: function cross(vector) {
      var B = vector.elements || vector;
      if (this.elements.length !== 3 || B.length !== 3) {
        return null;
      }
      var A = this.elements;
      return Vector.create([A[1] * B[2] - A[2] * B[1], A[2] * B[0] - A[0] * B[2], A[0] * B[1] - A[1] * B[0]]);
    }

    // Returns the (absolute) largest element of the vector

  }, {
    key: 'max',
    value: function max() {
      var m = 0;
      var i = this.elements.length;
      while (i--) {
        if (Math.abs(this.elements[i]) > Math.abs(m)) {
          m = this.elements[i];
        }
      }
      return m;
    }
  }, {
    key: 'maxIndex',
    value: function maxIndex() {
      var m = 0;
      var i = this.elements.length;
      var maxIndex = -1;

      while (i--) {
        if (Math.abs(this.elements[i]) > Math.abs(m)) {
          m = this.elements[i];
          maxIndex = i + 1;
        }
      }

      return maxIndex;
    }

    // Returns the index of the first match found

  }, {
    key: 'indexOf',
    value: function indexOf(x) {
      var index = null;
      var n = this.elements.length;
      for (var i = 0; i < n; i++) {
        if (index === null && this.elements[i] === x) {
          index = i + 1;
        }
      }
      return index;
    }

    // Returns a diagonal matrix with the vector's elements as its diagonal elements

  }, {
    key: 'toDiagonalMatrix',
    value: function toDiagonalMatrix() {
      return _matrix.Matrix.Diagonal(this.elements);
    }

    // Returns the result of rounding the elements of the vector

  }, {
    key: 'round',
    value: function round() {
      return this.map(function (x) {
        return Math.round(x);
      });
    }

    // Transpose a Vector, return a 1xn Matrix

  }, {
    key: 'transpose',
    value: function transpose() {
      var rows = this.elements.length;
      var elements = [];

      for (var i = 0; i < rows; i++) {
        elements.push([this.elements[i]]);
      }
      return _matrix.Matrix.create(elements);
    }

    // Returns a copy of the vector with elements set to the given value if they
    // differ from it by less than Sylvester.precision

  }, {
    key: 'snapTo',
    value: function snapTo(x) {
      return this.map(function (y) {
        return Math.abs(y - x) <= _sylvester.Sylvester.precision ? x : y;
      });
    }

    // Returns the vector's distance from the argument, when considered as a point in space

  }, {
    key: 'distanceFrom',
    value: function distanceFrom(obj) {
      if (obj.anchor || obj.start && obj.end) {
        return obj.distanceFrom(this);
      }
      var V = obj.elements || obj;
      if (V.length !== this.elements.length) {
        return null;
      }
      var sum = 0;
      var part = void 0;
      this.each(function (x, i) {
        part = x - V[i - 1];
        sum += part * part;
      });
      return Math.sqrt(sum);
    }

    // Returns true if the vector is point on the given line

  }, {
    key: 'liesOn',
    value: function liesOn(line) {
      return line.contains(this);
    }

    // Return true iff the vector is a point in the given plane

  }, {
    key: 'liesIn',
    value: function liesIn(plane) {
      return plane.contains(this);
    }

    // Rotates the vector about the given object. The object should be a
    // point if the vector is 2D, and a line if it is 3D. Be careful with line directions!

  }, {
    key: 'rotate',
    value: function rotate(t, obj) {
      var V = void 0;
      var R = null;
      var x = void 0;
      var y = void 0;
      var z = void 0;
      var C = void 0;
      if (t.determinant) {
        R = t.elements;
      }
      switch (this.elements.length) {
        case 2:
          V = obj.elements || obj;
          if (V.length !== 2) {
            return null;
          }
          if (!R) {
            R = _matrix.Matrix.Rotation(t).elements;
          }
          x = this.elements[0] - V[0];
          y = this.elements[1] - V[1];
          return Vector.create([V[0] + R[0][0] * x + R[0][1] * y, V[1] + R[1][0] * x + R[1][1] * y]);
        case 3:
          if (!obj.direction) {
            return null;
          }
          C = obj.pointClosestTo(this).elements;
          if (!R) {
            R = _matrix.Matrix.Rotation(t, obj.direction).elements;
          }
          x = this.elements[0] - C[0];
          y = this.elements[1] - C[1];
          z = this.elements[2] - C[2];
          return Vector.create([C[0] + R[0][0] * x + R[0][1] * y + R[0][2] * z, C[1] + R[1][0] * x + R[1][1] * y + R[1][2] * z, C[2] + R[2][0] * x + R[2][1] * y + R[2][2] * z]);
        default:
          return null;
      }
    }

    // Returns the result of reflecting the point in the given point, line or plane

  }, {
    key: 'reflectionIn',
    value: function reflectionIn(obj) {
      if (obj.anchor) {
        // obj is a plane or line
        var P = this.elements.slice();
        var C = obj.pointClosestTo(P).elements;
        return Vector.create([C[0] + (C[0] - P[0]), C[1] + (C[1] - P[1]), C[2] + (C[2] - (P[2] || 0))]);
      }

      // obj is a point
      var Q = obj.elements || obj;
      if (this.elements.length !== Q.length) {
        return null;
      }
      return this.map(function (x, i) {
        return Q[i - 1] + (Q[i - 1] - x);
      });
    }

    // Utility to make sure vectors are 3D. If they are 2D, a zero z-component is added

  }, {
    key: 'to3D',
    value: function to3D() {
      var V = this.dup();
      switch (V.elements.length) {
        case 3:
          break;
        case 2:
          V.elements.push(0);
          break;
        default:
          return null;
      }
      return V;
    }

    // Returns a string representation of the vector

  }, {
    key: 'inspect',
    value: function inspect() {
      return 'Vector<[' + this.elements.join(', ') + ']>';
    }

    // Set vector's elements from an array

  }, {
    key: 'setElements',
    value: function setElements(els) {
      this.elements = (els.elements || els).slice();
      return this;
    }
  }, {
    key: 'toJSON',
    value: function toJSON() {
      return this.elements;
    }

    // Constructor function

  }], [{
    key: 'create',
    value: function create(elements) {
      var V = new Vector();
      return V.setElements(elements);
    }

    // Random vector of size n

  }, {
    key: 'Random',
    value: function Random(n) {
      var elements = [];
      while (n--) {
        elements.push(Math.random());
      }
      return Vector.create(elements);
    }
  }, {
    key: 'Fill',
    value: function Fill(n, v) {
      var elements = [];
      while (n--) {
        elements.push(v);
      }
      return Vector.create(elements);
    }

    // Vector filled with zeros

  }, {
    key: 'Zero',
    value: function Zero(n) {
      return Vector.Fill(n, 0);
    }
  }, {
    key: 'One',
    value: function One(n) {
      return Vector.Fill(n, 1);
    }
  }, {
    key: 'log',
    value: function log(v) {
      return v.map(function (x) {
        return Math.log(x);
      });
    }
  }]);

  return Vector;
}();

// i, j, k unit vectors


Vector.i = Vector.create([1, 0, 0]);
Vector.j = Vector.create([0, 1, 0]);
Vector.k = Vector.create([0, 0, 1]);

// The following are shims for deprecated methods removed in 1.0.0
Vector.prototype.modulus = Vector.prototype.magnitude;
Vector.prototype.norm = Vector.prototype.magnitude;
Vector.prototype.dup = function () {
  return this.map(function (x) {
    return x;
  });
};
},{"./matrix":7,"./sylvester":9}],11:[function(require,module,exports){
module.exports = function () {
  this.argname
  this.argexpr
}

},{}],12:[function(require,module,exports){
module.exports = function () {
  this.argnames = []
  this.argexpr = []
}

},{}],13:[function(require,module,exports){
var Context = require('./Context')
var Globals = require('./Globals')
var _ = require('lodash')

function CSGModule(factory, csgOperation){
  this.csgOperation = csgOperation;
  this.factory = factory;
};

CSGModule.prototype.evaluate = function(parentContext, inst){
  var context = new Context(parentContext);

  var childModules = []

  for (var i = 0; i < inst.children.length; i++) {

      var childInst = inst.children[i];
      childInst.argvalues = [];
      _.each(childInst.argexpr, function(expr,index,list) {
          childInst.argvalues.push(expr.evaluate(context));
      });

      var childAdaptor = this.factory.getAdaptor(childInst);
      var evaluatedChild = childAdaptor.evaluate(parentContext, childInst);
      if (evaluatedChild !== undefined){
          childModules.push(evaluatedChild);
      }
  };

  if (childModules.length <= 1){
      return childModules[0];
  } else {
      return childModules[0] + "."+this.csgOperation+"([" + childModules.slice(1).join(',\n') + "])";
  }
};

module.exports = CSGModule

},{"./Context":15,"./Globals":19,"lodash":2}],14:[function(require,module,exports){
var _ = require('lodash')
var Context = require('./Context')
var Globals = require('./Globals')

function Child(factory){
this.factory = factory;
};

Child.prototype.evaluate = function(parentContext, inst){

    inst.argvalues = [];
    _.each(inst.argexpr, function(expr,index,list) {
        inst.argvalues.push(expr.evaluate(parentContext));
    });

    var context = Context.newContext(parentContext, [], [], inst);

    var childIndex = 0;
    if (inst.argvalues[0] !== undefined){
        childIndex = inst.argvalues[0];
    }

    var evaluatedChildren = [];

    for (var i = Globals.context_stack.length - 1; i >= 0; i--) {
        var ctx = Globals.context_stack[i];

        if (ctx.inst_p !== undefined){
            if (childIndex < ctx.inst_p.children.length) {

                var childInst = ctx.inst_p.children[childIndex];

                _.each(childInst.argexpr, function(expr,index,list) {
                    childInst.argvalues.push(expr.evaluate(ctx.inst_p.ctx));
                });

                var childAdaptor = this.factory.getAdaptor(childInst);
                evaluatedChildren.push(childAdaptor.evaluate(ctx.inst_p.ctx, childInst));

            }
            return evaluatedChildren;
        }
        ctx = ctx.parentContext;
    };

    return undefined;
};

module.exports =  Child

},{"./Context":15,"./Globals":19,"lodash":2}],15:[function(require,module,exports){
var _ = require('lodash')
var Globals = require('./Globals')

function Context(parentContext) {
  this.vars = (parentContext)? {} : {
      "$fn": Globals.FN_DEFAULT,
      "$fs": Globals.FS_DEFAULT,
      "$fa": Globals.FA_DEFAULT
  };
  this.parentContext = parentContext;
  this.inst_p;
  this.functions_p = {};
  this.modules_p = {};
  Globals.context_stack.push(this);
};

Context.prototype.setVariable = function(name, value) {
  if (value !== undefined){
      this.vars[name] = value;
  }
};

Context.prototype.args = function(argnames, argexpr, call_argnames, call_argvalues) {

  for (var i = 0; i < argnames.length; i++) {
      if (i < argexpr.length && argexpr[i] !== undefined){
          this.setVariable(argnames[i], argexpr[i].evaluate(this.parentContext));
      } else {
          this.setVariable(argnames[i], undefined);
      }
  };
  var posarg = 0;
  for (var i = 0; i < call_argnames.length; i++) {
      if (call_argnames[i] === undefined) {
          if (posarg < argnames.length){
              this.setVariable(argnames[posarg++], call_argvalues[i]);
          }
      } else {
          this.setVariable(call_argnames[i], call_argvalues[i]);
      }
  }
};

Context.prototype.lookupVariable = function(name) {

  if (_.has(this.vars, name)){
      return this.vars[name];
  }

  if (this.parentContext !== undefined){
      return this.parentContext.lookupVariable(name);
  }

  //console.log("WARNING: Ignoring unknown variable '"+name+"'.");
  return undefined;
};


Context.prototype.evaluateFunction = function(name, argnames, argvalues) {

  if (_.has(this.functions_p, name)){
      return this.functions_p[name].evaluate(this, argnames, argvalues);
  }

  if (_.has(functionNameLookup, name)){
      return functionNameLookup[name].apply(this, argvalues);
  }

  if (this.parentContext !== undefined){
      return this.parentContext.evaluateFunction(name, argnames, argvalues);
  }

  console.log("WARNING: Ignoring unknown function '"+name+"'.");
  return undefined;
};

Context.prototype.evaluateModule = function(inst, factory) {

  var that = this;

  var customModule = _.find(this.modules_p, function(x) { return x.name == inst.name; });
  if (customModule !== undefined) {
      return customModule.evaluate(this, inst);
  }

  if (inst.isSubmodule === undefined || !inst.isSubmodule){
      var adaptor = factory.getAdaptor(inst);
      if (adaptor !== undefined){
          return adaptor.evaluate(this, inst);
      }
  }

  if (this.parentContext) {
      return this.parentContext.evaluateModule(inst, factory);
  }

  console.log("WARNING: Ignoring unknown module: " + inst.name);
  return undefined;
};

Context.newContext = function (parentContext, argnames, argexpr, inst) {
  var context = new Context(parentContext);
  context.args(argnames, argexpr, inst.argnames, inst.argvalues);
  return context;
};

Context.contextVariableLookup = function(context, name, defaultValue){
  var val = context.lookupVariable(name);
  if (val === undefined){
      val = defaultValue;
  }
  return val;
}

Context.printContext = function(c){
  console.log(c.vars);
  if (c.parentContext){
      Context.printContext(c.parentContext);
  }
};

/*
  Returns the number of subdivision of a whole circle, given radius and
  the three special variables $fn, $fs and $fa
*/
Context.get_fragments_from_r = function(r, context) {
  var fn = Context.contextVariableLookup(context, "$fn", Globals.FN_DEFAULT);
  var fs = Context.contextVariableLookup(context, "$fs", Globals.FS_DEFAULT);
  var fa = Context.contextVariableLookup(context, "$fa", Globals.FA_DEFAULT);

  var GRID_FINE   = 0.000001;
  if (r < GRID_FINE) return 0;
  if (fn > 0.0)
      return parseInt(fn);
  return parseInt(Math.ceil(Math.max(Math.min(360.0 / fa, r*2*Math.PI / fs), 5)));
};

function rad2deg(rad){
  return rad * (180/Math.PI);
};

function deg2rad(deg){
  return deg * Math.PI/180.0;
};

var functionNameLookup = {
  "cos":function(degree) {
      if (_.isUndefined(degree)  || _.isNaN(degree)){return undefined;}
      return Math.cos(deg2rad(degree));
  },
  "sin":function(degree) {
      if (_.isUndefined(degree)  || _.isNaN(degree)){return undefined;}
      return Math.sin(deg2rad(degree));
  },
  "acos":function(degree) {
      if (_.isUndefined(degree)  || _.isNaN(degree)){return undefined;}
      return rad2deg(Math.acos(degree));
  },
  "asin":function(degree) {
      if (_.isUndefined(degree)  || _.isNaN(degree)){return undefined;}
      return rad2deg(Math.asin(degree));
  },
  "atan":function(degree) {
      if (_.isUndefined(degree)  || _.isNaN(degree)){return undefined;}
      return rad2deg(Math.atan(degree));
  },
  "atan2":function(x,y) {
      if (_.isUndefined(x) || _.isNaN(x) || _.isUndefined(y) || _.isNaN(y)){return undefined;}
      return rad2deg(Math.atan2(x,y));
  },
  "tan":function(degree) {
      if (_.isUndefined(degree)  || _.isNaN(degree)){return undefined;}
      return Math.tan(deg2rad(degree));
  },
  "rands":function(min_value,max_value,value_count, seed_value){
      var values = [];
      if (seed_value !== undefined){
          Math.seedrandom(seed_value);
      }
      for (var i=0;i<value_count;i++){
          var random_value = min_value+(Math.random()*(max_value-min_value));
          values[i] = random_value;
      }
      return values;
  },
  "round":function(x){
      if (_.isUndefined(x)  || _.isNaN(x)){return undefined;}

      // This is because Javascript rounds negative numbers up, whereas c++ rounds down
      return (x<0)? -(Math.round(Math.abs(x))) : Math.round(x);
  },
  "exp":function(x) {
      if (_.isUndefined(x)  || _.isNaN(x)){return undefined;}

      return Math.exp(x);
  },
  "abs":function(x){
      if (_.isUndefined(x)  || _.isNaN(x)){return undefined;}
      return Math.abs(x);
  },
  "max":function(){
      return Math.max.apply(null, _.map(arguments, function(num){ return num ? num : -Infinity; }));
  },
  "min":function(){
      return Math.min.apply(null, _.map(arguments, function(num){ return num ? num : Infinity; }));
  },
  "pow":function(x) {
      if (_.isUndefined(x)  || _.isNaN(x)){return undefined;}
      return Math.pow(x);
  },
  "ln":function(x) {
      if (_.isUndefined(x)  || _.isNaN(x)){return undefined;}
      return Math.log(x);
  },
  "ceil":function(x) {
      if (_.isUndefined(x)  || _.isNaN(x)){return undefined;}
      return Math.ceil(x);
  },
  "floor":function(x) {
      if (_.isUndefined(x)  || _.isNaN(x)){return undefined;}
      return Math.floor(x);
  },
  "sqrt":function(x) {
      if (_.isUndefined(x)  || _.isNaN(x)){return undefined;}
      return Math.sqrt(x);
  },
  "len":function(x){
      if (_.isUndefined(x)  || _.isNaN(x)){return undefined;}
      var y = _.isString(x) ? Globals.stripString(x) : x;
      return y.length;
  },
  "log":function(){
      if (arguments.length == 2){
          if (_.isUndefined(arguments[0])  || _.isNaN(arguments[0])||_.isUndefined(arguments[1])  || _.isNaN(arguments[1])){return undefined;}
          return Math.log(arguments[1])/Math.log(arguments[0]);
      } else if (arguments.length == 1){
          if (_.isUndefined(arguments[0])  || _.isNaN(arguments[0])){return undefined;}
          return Math.log(arguments[0]) / Math.log(10.0);
      } else {
          return undefined;
      }
  },
  "str":function(){
      var vals = [];
      _.each(arguments, function(x){
          vals.push(Globals.convertForStrFunction(x));
      });

      return vals.join('');
  },
  "sign": function(x){
      if (_.isUndefined(x)  || _.isNaN(x)){return undefined;}
      return (x > 0)? 1.0 : ((x < 0)? -1.0 : 0);
  },
  "lookup": function(){
      var low_p, low_v, high_p, high_v;
      if (arguments.length < 2){
          console.log("Lookup arguments are invalid. Incorrect parameter count. " +  arguments);
          return undefined;
      }

      var p = arguments[0];
      var vector = arguments[1];
      if (!_.isNumber(p)        ||      // First must be a number
          !_.isArray(vector)      ||      // Second must be a vector of vectors
          vector.length < 2       ||
          (vector.length >=2 && !_.isArray(vector[0]))
          ){
          console.log("Lookup arguments are invalid. Incorrect parameters. " +  arguments);
          return undefined;
      }

      if (vector[0].length != 2){
          console.log("Lookup arguments are invalid. First vector has incorrect number of values. " +  p + ",  " + vector);
          return undefined;
      }
      low_p = vector[0][0];
      low_v = vector[0][1];
      high_p = low_p;
      high_v = low_v;

      _.each(vector.slice(1), function(v){
          if (v.length == 2){
              var this_p = v[0];
              var this_v = v[1];

              if (this_p <= p && (this_p > low_p || low_p > p)) {
                  low_p = this_p;
                  low_v = this_v;
              }
              if (this_p >= p && (this_p < high_p || high_p < p)) {
                  high_p = this_p;
                  high_v = this_v;
              }
          }
      });

      if (p <= low_p){
          return low_v;
      }

      if (p >= high_p){
          return high_v;
      }

      var f = (p-low_p) / (high_p-low_p);
      return high_v * f + low_v * (1-f);
  }

};

module.exports =  Context

},{"./Globals":19,"lodash":2}],16:[function(require,module,exports){
var _ = require('lodash')
var Context = require('./Context')
var Globals = require('./Globals')
var Range = require('./Range')

function ControlModule(factory){
  this.factory = factory;
};

function IfStatement(a){
  ControlModule.call(this, a);
};

IfStatement.prototype.evaluate = function(parentContext, inst){
  inst.argvalues = [];

  _.each(inst.argexpr, function(expr,index,list) {
      inst.argvalues.push(expr.evaluate(parentContext));
  });

  var context = Context.newContext(parentContext, [], [], inst);

  var childrenToEvaluate = (inst.argvalues.length > 0 && inst.argvalues[0])? inst.children : inst.else_children;

  var childModules = [];

  for (var i = 0; i < childrenToEvaluate.length; i++) {

      var childInst = childrenToEvaluate[i];

      childInst.argvalues = [];

      _.each(childInst.argexpr, function(expr,index,list) {
          childInst.argvalues.push(expr.evaluate(context));
      });

      var childAdaptor = this.factory.getAdaptor(childInst);

      childModules.push(childAdaptor.evaluate(context, childInst));
  };
  if (_.isEmpty(childModules)){
      return undefined;
  } else {
      if (childModules.length > 1){
          return _.first(childModules)+".union([" + _.tail(childModules) + "])";
      } else {
          return childModules[0];
      }
  }
};

function ForLoopStatement(factory, args){
  ControlModule.call(this, factory);
  this.csgOp = args.csgOp;
  this.evaluatedChildren = [];

  this.forEval = function(parentEvaluatedChildren, inst, recurs_length, call_argnames, call_argvalues, arg_context) {

      this.evaluatedChildren = parentEvaluatedChildren;

      if (call_argnames.length > recurs_length) {
          var it_name = call_argnames[recurs_length];
          var it_values = call_argvalues[recurs_length];
          var context = new Context(arg_context);

          if (it_values instanceof Range) {
              var range = it_values;
              if (range.end < range.begin) {
                  var t = range.begin;
                  range.begin = range.end;
                  range.end = t;
              }
              if (range.step > 0 && (range.begin-range.end)/range.step < 10000) {
                  for (var i = range.begin; i <= range.end; i += range.step) {
                      context.setVariable(it_name, i);
                      this.forEval(this.evaluatedChildren, inst, recurs_length+1, call_argnames, call_argvalues, context);
                  }
              }
          }
          else if (_.isArray(it_values)) {
              for (var i = 0; i < it_values.length; i++) {
                  context.setVariable(it_name, it_values[i]);
                  this.forEval(this.evaluatedChildren, inst, recurs_length+1, call_argnames, call_argvalues, context);
              }
          }
      } else if (recurs_length > 0) {
          var evaluatedInstanceChildren = inst.evaluateChildren(arg_context);
          if (_.isArray(evaluatedInstanceChildren)){
              this.evaluatedChildren = this.evaluatedChildren.concat(evaluatedInstanceChildren);
          } else {
              this.evaluatedChildren.push(evaluatedInstanceChildren);
          }
      }
      if (_.isArray(this.evaluatedChildren)){
          // remove empty arrays (e.g. for loops containing only echo statements)
          this.evaluatedChildren = _.reject(this.evaluatedChildren, function(x){ return _.isEmpty(x); });
      }

      // Note: we union here so subsequent actions (e.g. translate) can be performed on the entire result of the for loop.
      if (_.isArray(this.evaluatedChildren) && this.evaluatedChildren.length > 1){
          var unionedEvaluatedChildren = _.first(this.evaluatedChildren)+"."+this.csgOp+"([" + _.tail(this.evaluatedChildren) + "])";
          this.evaluatedChildren = [unionedEvaluatedChildren];
      }

      return this.evaluatedChildren;
  };
};

ForLoopStatement.prototype.evaluate = function(context, inst) {

  if (inst.context === undefined){
      inst.context = context;
  }
  return this.forEval([], inst, 0, inst.argnames, inst.argvalues, inst.context);
};

function Echo(a){
  ControlModule.call(this, a);
};

Echo.prototype.evaluate = function(parentContext, inst){
  var context = new Context(parentContext);
  var argvalues = [];

  _.each(inst.argexpr, function(expr,index,list) {
      argvalues.push(Globals.convertForStrFunction(expr.evaluate(context)));
  });

  console.log(_.template("ECHO: <%=argvalues%>")({argvalues:argvalues}));

  return undefined;
};


module.exports = {
	Echo: Echo,
	ForLoopStatement: ForLoopStatement,
	IfStatement: IfStatement
}

},{"./Context":15,"./Globals":19,"./Range":28,"lodash":2}],17:[function(require,module,exports){
var Range = require('./Range')
var Sylvester = require('sylvester')
var _ = require('lodash')


function Expression(value) {
  this.children = [];
  this.const_value = value;
  this.var_name;
  this.call_funcname;
  this.call_argnames = [];
  this.type = "C";
};

function isMatrix(x){
  return _.isArray(x) && _.isArray(x[0]);
}

function isVector(x){
  return _.isArray(x) && !_.isArray(x[0]);
}

function getValueObject(x){
  if (isMatrix(x)){
      return Sylvester.$M(x);
  } else if (isVector(x)){
      return Sylvester.$V(x);
  } else {
      return x;
  }
}

Sylvester.Matrix.prototype.toString = function(){
  var x = _.map(this.elements, function(y){ return "["+y.join(',')+"]"; });
  return "["+x.join(',')+"]";
}

Sylvester.Vector.prototype.toString = function(){
  return "["+this.elements.join(',')+"]";
}

Expression.prototype.evaluate = function(context) {
  switch (this.type){

      case "!":
          return ! this.children[0].evaluate(context);
          break;
      case "&&":
          var c1 = this.children[0].evaluate(context);
          var c2 = this.children[1].evaluate(context);

          if (_.isUndefined(c1) || _.isUndefined(c2) || _.isNaN(c1) || _.isNaN(c2)){
              return false;
          }

          if (_.isArray(c1) || _.isArray(c2)){
              return true;
          }

          return c1 && c2;
          break;
      case "||":
          var c1 = this.children[0].evaluate(context);
          var c2 = this.children[1].evaluate(context);

          if (_.isUndefined(c1) || _.isUndefined(c2) || _.isNaN(c1) || _.isNaN(c2)){
              return true;
          }

          if (_.isArray(c1) || _.isArray(c2)){
              return true;
          }
          return c1 || c2;
          break;
      case "*":
          var c1 = this.children[0].evaluate(context);
          var c2 = this.children[1].evaluate(context);

          if (_.isUndefined(c1) || _.isUndefined(c2) || _.isNaN(c1) || _.isNaN(c2)){
              return undefined
          }

          if (_.isArray(c1) || _.isArray(c2)){

              var v1 = getValueObject(c1);
              var v2 = getValueObject(c2);

              if (isVector(c1) && isVector(c2)){
                  return v1.dot(v2);
              }

              if (isVector(c1) && isMatrix(c2)){
                  return [v1.dot(v2.col(1)),
                          v1.dot(v2.col(2)),
                          v1.dot(v2.col(3))];
              }

              if (_.isNumber(c1)){
                  return v2.multiply(v1);
              }

              return (v1.multiply(v2));

          }

          return c1 * c2;

          break;
      case "/":
          var c1 = this.children[0].evaluate(context);
          var c2 = this.children[1].evaluate(context);

          if (_.isUndefined(c1) || _.isUndefined(c2) || _.isNaN(c1) || _.isNaN(c2)){
              return undefined
          }

          if (_.isArray(c1) || _.isArray(c2)){

              var v1 = getValueObject(c1);
              var v2 = getValueObject(c2);

              if (_.isArray(c1) && _.isArray(c2)){
                  return undefined;
              }

              if (isMatrix(c1) && _.isNumber(c2)){
                  return v1.multiply(1/v2);
              }

              if (_.isNumber(c1) && isMatrix(c2)){
                  var result = [];

                  for (var i = 0; i < c2.length; i++){
                      var a1 = [];
                      for (var j = 0; j < c2[i].length; j++){
                          a1[j] = c1 / c2[i][j];
                      }
                      result.push(a1);
                  }
                  return result;
              }

              if (isVector(c1) && _.isNumber(c2)) {
                  return v1.multiply(1/v2);
              }

              if (_.isNumber(c1) && isVector(c2)) {
                  return v2.multiply(1/v1);
              }
          }

          return c1 / c2;

          break;
      case "%":
          var c1 = this.children[0].evaluate(context);
          var c2 = this.children[1].evaluate(context);

          if (_.isUndefined(c1) || _.isUndefined(c2) || _.isNaN(c1) || _.isNaN(c2)){
              return undefined
          }

          if (_.isArray(c1) || _.isArray(c2)){
              return undefined;
          }

          return c1 % c2;
          break;
      case "+":
          var c1 = this.children[0].evaluate(context);
          var c2 = this.children[1].evaluate(context);

          if (_.isUndefined(c1) || _.isUndefined(c2) || _.isNaN(c1) || _.isNaN(c2)){
              return undefined
          }

          if (_.isArray(c1) && _.isArray(c2)){
              //matrices
              if (isMatrix(c1) && isMatrix(c2)){
                  var minLength = Math.min(c1.length, c2.length);
                  var result = [];

                  for (var i = 0; i < minLength; i++){
                      var a1 = [];
                      for (var j = 0; j < c1[i].length; j++){
                          a1[j] = c1[i][j] + c2[i][j];
                      }
                      result.push(a1);
                  }
                  return result;
              } else if (isMatrix(c1) || isMatrix(c2)){
                  return undefined;
              }
              return [c1[0] + c2[0], c1[1] + c2[1], c1[2] + c2[2]];
          } else if (_.isArray(c1) || _.isArray(c2)){
              return undefined;
          } else {
              return c1 + c2;
          }
          break;
      case "-":
          var c1 = this.children[0].evaluate(context);
          var c2 = this.children[1].evaluate(context);

          if (_.isUndefined(c1) || _.isUndefined(c2) || _.isNaN(c1) || _.isNaN(c2)){
              return undefined
          }

          if (_.isArray(c1) && _.isArray(c2)){

              //matrices
              if (_.isArray(c1[0]) && _.isArray(c2[0])){
                  var minLength = Math.min(c1.length, c2.length);
                  var result = [];

                  for (var i = 0; i < minLength; i++){
                      var a1 = [];
                      for (var j = 0; j < c1[i].length; j++){
                          a1[j] = c1[i][j] - c2[i][j];
                      }
                      result.push(a1);
                  }
                  return result;
              }

              return [c1[0] - c2[0], c1[1] - c2[1], c1[2] - c2[2]];
          } else if (_.isArray(c1) || _.isArray(c2)){
              return undefined;
          } else {
              return c1 - c2;
          }
          break;
      case "<":
          var c1 = this.children[0].evaluate(context);
          var c2 = this.children[1].evaluate(context);

          if (_.isUndefined(c1) || _.isUndefined(c2) || _.isNaN(c1) || _.isNaN(c2)){
              return false;
          }

          if (_.isArray(c1) || _.isArray(c2)){
              return false;
          }
          return c1 < c2;
          break;
      case "<=":
          var c1 = this.children[0].evaluate(context);
          var c2 = this.children[1].evaluate(context);

          if (_.isUndefined(c1) || _.isUndefined(c2) || _.isNaN(c1) || _.isNaN(c2)){
              return true;
          }

          if (_.isArray(c1) || _.isArray(c2)){
              return true;
          }
          return c1 <= c2;
          break;
      case "==":
          var c1 = this.children[0].evaluate(context);
          var c2 = this.children[1].evaluate(context);

          if (_.isUndefined(c1) || _.isUndefined(c2) || _.isNaN(c1) || _.isNaN(c2)){
              return false;
          }

          if ((isVector(c1) && isVector(c2))
              || (isMatrix(c1) && isMatrix(c2))){
              var v1 = getValueObject(c1);
              var v2 = getValueObject(c2);
              return v1.eql(v2);
          }
          if (_.isArray(c1) || _.isArray(c2)){
              return false;
          }
          return c1 == c2;
          break;
      case "!=":
          var c1 = this.children[0].evaluate(context);
          var c2 = this.children[1].evaluate(context);

          if (_.isUndefined(c1) || _.isUndefined(c2) || _.isNaN(c1) || _.isNaN(c2)){
              return false;
          }

          if ((isVector(c1) && isVector(c2))
              || (isMatrix(c1) && isMatrix(c2))){
              var v1 = getValueObject(c1);
              var v2 = getValueObject(c2);
              return !v1.eql(v2);
          }

          if (_.isArray(c1) || _.isArray(c2)){
              return true;
          }
          return c1 != c2;
          break;
      case ">=":
          var c1 = this.children[0].evaluate(context);
          var c2 = this.children[1].evaluate(context);

          if (_.isUndefined(c1) || _.isUndefined(c2) || _.isNaN(c1) || _.isNaN(c2)){
              return true;
          }

          if (_.isArray(c1) || _.isArray(c2)){
              return true;
          }

          return c1 >= c2;
          break;
      case ">":
          var c1 = this.children[0].evaluate(context);
          var c2 = this.children[1].evaluate(context);

          if (_.isUndefined(c1) || _.isUndefined(c2) || _.isNaN(c1) || _.isNaN(c2)){
              return false;
          }

          if (_.isArray(c1) || _.isArray(c2)){
              return false;
          }

          return c1 > c2;
          break;
      case "?:":
          var v = this.children[0].evaluate(context);
          return this.children[v ? 1 : 2].evaluate(context);
          break;
      case "I":

          var c1 = this.children[0].evaluate(context);

          if (_.isArray(c1)){

              return _.map(c1, function(x){return -x;})
          }

          return -c1;
          break;
      case "C":
          return this.const_value;
          break;
      case "R":
          var v1 = this.children[0].evaluate(context);
          var v2 = this.children[1].evaluate(context);
          var v3 = this.children[2].evaluate(context);
          if (_.isNumber(v1) && _.isNumber(v2) && _.isNumber(v3)) {
              return new Range(v1, v2, v3);
          }
          return undefined;
          break;
      case "V":
          var vec = [];
          for (var i = 0; i < this.children.length; i++) {
              vec.push(this.children[i].evaluate(context));
          };
          return vec;
          break;
      case "L":
          return context.lookupVariable(this.var_name);
          break;
      case "[]":
          return this.children[0].evaluate(context)[this.children[1].evaluate(context)];
          break;
      case "F":
          var argvalues =[];
          for (var i = 0; i < this.children.length; i++){
                argvalues.push(this.children[i].evaluate(context));
          }

          return context.evaluateFunction(this.call_funcname, this.call_argnames, argvalues);
          break;
      default:
          console.log("todo - evaluate expression", this);
  }
};
module.exports =  Expression

},{"./Range":28,"lodash":2,"sylvester":5}],18:[function(require,module,exports){
var Context = require('./Context')

function FunctionDef () {
  this.argnames = []
  this.argexpr = []
  this.expr
}

FunctionDef.prototype.evaluate = function (parentContext, call_argnames, call_argvalues) {
  var context = new Context(parentContext)
  context.args(this.argnames, this.argexpr, call_argnames, call_argvalues)

  if (this.expr !== undefined) {
    return this.expr.evaluate(context)
  }

  return undefined
}

module.exports = FunctionDef

},{"./Context":15}],19:[function(require,module,exports){
var _ = require('lodash')

var singleLineModuleRegex = /(module\s*\w*\([^\)]*\)[\w\n]*)([^{};]*);/gm;
var singleLineModuleReplacement = "$1 {$2;};";
var multiLineCommentRegex = /((?:\/\*(?:[^*]|(?:\*+[^*\/]))*\*+\/)|(?:\/\/.*))/gm;

function stripString (s) {
  if (/^\".*\"$/.test(s)){
      return s.match(/^\"(.*)\"$/)[1];
  } else {
      return s;
  }
}

function convertForStrFunction(val){
  if (_.isString(val)){
      return stripString(val);
  }

  if (_.isArray(val)){
      var mapped = _.map(val, function (value, key, list) {
          return convertForStrFunction(value);
      });

      return "["+mapped.join(',')+"]";
  }

  return val;
}

function preParse(text){
  return text
    .replace(multiLineCommentRegex, '')
    .replace(singleLineModuleRegex, singleLineModuleReplacement)
}

module.exports =  {
  DEFAULT_RESOLUTION: 16,
  DEFAULT_2D_RESOLUTION: 16,
  FN_DEFAULT: 0,
  FS_DEFAULT: 2.0,
  FA_DEFAULT: 12.0,
  module_stack: [],
  context_stack: [],
  stripString: stripString,
  convertForStrFunction: convertForStrFunction,
  preParse: preParse,
  importedObjectRegex: /import\([^\"]*\"([^\)]*)\"[,]?.*\);?/gm,
  usedLibraryRegex: /use <([^>]*)>;?/gm,
  includedLibraryRegex: /include <([^>]*)>;?/gm
}

},{"lodash":2}],20:[function(require,module,exports){
var ModuleInstantiation = require('./ModuleInstantiation')

function IfElseModuleInstantiation () {
  ModuleInstantiation.call(this)
  this.name = 'if'
  this.else_children = []
}

IfElseModuleInstantiation.prototype = new ModuleInstantiation()
IfElseModuleInstantiation.prototype.constructor = IfElseModuleInstantiation

module.exports = IfElseModuleInstantiation

},{"./ModuleInstantiation":24}],21:[function(require,module,exports){
var Context = require('./Context')
var Globals = require('./Globals')
var StlDecoder = require('./StlDecoder')

function Import (factory) {
  this.factory = factory
}

Import.prototype.evaluate = function (parentContext, inst) {
  var context = new Context(parentContext)

  var argnames = ['file', 'filename', 'convexity']
  var argexpr = []

  context.args(argnames, argexpr, inst.argnames, inst.argvalues)

  var filename = Context.contextVariableLookup(context, 'file', null) || Context.contextVariableLookup(context, 'filename', null)

  var convexity = Context.contextVariableLookup(context, 'convexity', 5)

  var importCache = Context.contextVariableLookup(context, 'importCache', {})

  var fileContents = importCache[filename]

  if (fileContents !== undefined) {
    var stlDecoder = new StlDecoder(atob(fileContents))
    stlDecoder.decode()
    return stlDecoder.getCSGString()
  }

  return undefined
}

module.Exports = Import

},{"./Context":15,"./Globals":19,"./StlDecoder":29}],22:[function(require,module,exports){
var _ = require('lodash')
var Context = require('./Context')
var Globals = require('./Globals')


function Module(name) {
  this.name = name;
  this.children = [];
  this.assignments_var = {};
  this.functions = {};
  this.modules = [];
  this.argnames = [];
  this.argexpr = [];
};

Module.prototype.evaluate = function(parentContext, inst) {
  var lines = [];

  var context = new Context(parentContext);

  if (parentContext === undefined){
      context.setVariable("$fn", Globals.DEFAULT_RESOLUTION);
      context.setVariable("$fs", 2.0);
      context.setVariable("$fa", 12.0);
  }

  if (inst !== undefined) {
      context.args(this.argnames, this.argexpr, inst.argnames, inst.argvalues);
      context.setVariable("$children", inst.children.length);
  }

  context.inst_p = inst;
  context.functions_p = this.functions;
  context.modules_p = this.modules;
  _.each(this.assignments_var, function(value, key, list) {
      context.setVariable(key, value.evaluate(context));
  });

  var controlChildren = _.filter(this.children, function(child){
      return child && child.name == "echo";
  });

  _.each(controlChildren, function(child, index, list) {
      child.evaluate(context);
  });

  var nonControlChildren = _.reject(this.children, function(child){
      return !child || child.name == "echo";
  });

  var evaluatedLines = [];
  _.each(nonControlChildren, function(child, index, list) {
      var evaluatedChild = child.evaluate(context)
      if (evaluatedChild == undefined || (_.isArray(evaluatedChild) && _.isEmpty(evaluatedChild))){
          // ignore
      } else {
          evaluatedLines.push(evaluatedChild);
      }
  });

  var cleanedLines = _.compact(evaluatedLines);
  if (cleanedLines.length == 1){
      lines.push(cleanedLines[0]);
  } else if (cleanedLines.length > 1){
      lines.push(_.head(cleanedLines)+".union([" +_.tail(cleanedLines)+"])");
  }

  return lines;
};

module.exports = Module

},{"./Context":15,"./Globals":19,"lodash":2}],23:[function(require,module,exports){
function ModuleAdaptor () {}

ModuleAdaptor.prototype.evaluate = function (parentContext, inst) {
  inst.isSubmodule = true
  return parentContext.evaluateModule(inst)
}

module.exports = ModuleAdaptor

},{}],24:[function(require,module,exports){
var _ = require('lodash')
var OpenjscadSolidFactorySingleton = require('./OpenjscadSolidFactorySingleton')

function ModuleInstantiation () {
  this.name
  this.argnames = []
  this.argvalues = []
  this.argexpr = []
  this.children = []
  this.isSubmodule = false
  this.context
}

ModuleInstantiation.prototype.evaluate = function (context) {
  var evaluatedModule

  // NOTE: not sure how we should handle this in javascript ... is it necessary?
  // if (this.context === null) {
  //    console.log("WARNING: Ignoring recursive module instantiation of ", this.name)
  // } else {
  var that = this

  this.argvalues = []

  _.each(this.argexpr, function (expr, index, list) {
    that.argvalues.push(expr.evaluate(context))
  })

  that.context = context

  evaluatedModule = context.evaluateModule(that, OpenjscadSolidFactorySingleton.getInstance())

  that.context = null
  that.argvalues = []

  // }
  return evaluatedModule
}

ModuleInstantiation.prototype.evaluateChildren = function (context) {
  var childModules = []

  for (var i = 0; i < this.children.length; i++) {
    var childInst = this.children[i]

    var evaluatedChild = childInst.evaluate(context)
    if (evaluatedChild !== undefined) {
      childModules.push(evaluatedChild)
    }
  }

  return childModules
}

module.exports = ModuleInstantiation

},{"./OpenjscadSolidFactorySingleton":26,"lodash":2}],25:[function(require,module,exports){
var Context = require('./Context')
var Globals = require('./Globals')
var PrimitiveModules = require('./PrimitiveModules')
var TransformModules = require('./TransformModules')
var ControlModules = require('./ControlModules')
var CSGModule = require('./CSGModule')

var ChildModule = require('./ChildModule')
var ModuleAdaptor = require('./ModuleAdaptor')
var ImportModule = require('./ImportModule')

function OpenjscadSolidFactory () {}

OpenjscadSolidFactory.prototype.getAdaptor = function (args) {
  switch (args.name) {
    case 'cube':
      return new PrimitiveModules.Cube()
    case 'sphere':
      return new PrimitiveModules.Sphere()
    case 'cylinder':
      return new PrimitiveModules.Cylinder()
    case 'polyhedron':
      return new PrimitiveModules.Polyhedron()
    case 'circle':
      return new PrimitiveModules.Circle()
    case 'square':
      return new PrimitiveModules.Square()
    case 'polygon':
      return new PrimitiveModules.Polygon()
    case 'union':
      return new CSGModule(this, 'union')
    case 'difference':
      return new CSGModule(this, 'subtract')
    case 'intersect':
    case 'intersection':
      return new CSGModule(this, 'intersect')
    case 'translate':
      return new TransformModules.Translate(this)
    case 'scale':
      return new TransformModules.Scale(this)
    case 'rotate':
      return new TransformModules.Rotate(this)
    case 'mirror':
      return new TransformModules.Mirror(this)
    case 'linear_extrude':
      return new TransformModules.Extrude(this)
    case 'color':
      return new TransformModules.Color(this)
    case 'multmatrix':
      return new TransformModules.Multimatrix(this)
    case 'render':
    case 'assign': // Note: assign does the same as render in this case - re-evaluate the arguments and process the children.
      return new TransformModules.Render(this)
    case 'echo':
      return new ControlModules.Echo(this)
    case 'for':
      return new ControlModules.ForLoopStatement(this, {csgOp: 'union'})
    case 'intersection_for':
      return new ControlModules.ForLoopStatement(this, {csgOp: 'intersect'})
    case 'if':
      return new ControlModules.IfStatement(this)
    case 'import':
      return new ImportModule(this)
    case 'child':
      return new ChildModule(this)
    default:
      return new ModuleAdaptor()
  }
}

module.exports = OpenjscadSolidFactory

},{"./CSGModule":13,"./ChildModule":14,"./Context":15,"./ControlModules":16,"./Globals":19,"./ImportModule":21,"./ModuleAdaptor":23,"./PrimitiveModules":27,"./TransformModules":30}],26:[function(require,module,exports){
var OpenjscadSolidFactory = require('./OpenjscadSolidFactory')
var factory = new OpenjscadSolidFactory()

module.exports = {
  getInstance: function () {
    return factory
  }
}

},{"./OpenjscadSolidFactory":25}],27:[function(require,module,exports){
var _ = require('lodash')
var Context = require('./Context')
var Globals = require('./Globals')

function PrimitiveModule(){};

function Sphere(a){
	PrimitiveModule.call(this, a);
};

Sphere.prototype.evaluate = function(parentContext, inst){
var context = new Context(parentContext);

var argnames = ["r", "$fn"];
var argexpr = [];

context.args(argnames, argexpr, inst.argnames, inst.argvalues);

var r = Context.contextVariableLookup(context, "r", 1);

var resolution = Context.get_fragments_from_r(r, context);

var openjscadParameters = {center:[0,0,0], resolution:resolution, radius:r};

return _.template('CSG.sphere({center: [<%=String(center)%>], radius: <%= radius %>, resolution: <%= resolution%>})')(openjscadParameters);
}

function Cylinder(a){
PrimitiveModule.call(this, a);
};

Cylinder.prototype.evaluate = function(parentContext, inst) {

var context = new Context(parentContext);

var argnames = ["h", "r1", "r2", "center", "$fn", "$fa", "$fs"];
var argexpr = [];

context.args(argnames, argexpr, inst.argnames, inst.argvalues);

var openjscadArgs = {start: [0,0,0], end: [0,0,1], radiusStart: 1, radiusEnd: 1, resolution: Globals.DEFAULT_RESOLUTION};
var isCentered = Context.contextVariableLookup(context, "center", false);
var h = Context.contextVariableLookup(context, "h", 1);
var r = Context.contextVariableLookup(context, "r", 1);
var r1 = Context.contextVariableLookup(context, "r1", undefined);
var r2 = Context.contextVariableLookup(context, "r2", undefined);

var startZ = isCentered? -(h/2) : 0;
var endZ = isCentered? h/2 : h;

openjscadArgs.start = [0, 0, startZ];
openjscadArgs.end = [0, 0, endZ];

/* we have to check the context vars directly here in case a parent module in the context stack has the same parameters, e.g. r1 which would be used as default.
 Example testcad case:
      module ring(r1, r2, h) {
          cylinder(r = 3, h = h);
      }
      ring(8, 6, 10);
*/

if (_.has(context.vars, 'r')) {
  openjscadArgs.radiusStart = r;
  openjscadArgs.radiusEnd = r;
}
if (_.has(context.vars, 'r1')) {
  openjscadArgs.radiusStart = r1;
}
if (_.has(context.vars, 'r2')) {
  openjscadArgs.radiusEnd = r2;
}
openjscadArgs.resolution = Context.get_fragments_from_r(Math.max(openjscadArgs.radiusStart, openjscadArgs.radiusEnd), context);

if (openjscadArgs.radiusStart == 0 && openjscadArgs.radiusEnd == 0){
  return undefined;
}

return _.template('CSG.cylinder({start: [<%=start%>], end: [<%=end%>],radiusStart: <%=radiusStart%>, radiusEnd: <%=radiusEnd%>, resolution: <%=resolution%>})')(openjscadArgs);
};


function Cube(a){
PrimitiveModule.call(this, a);
};

Cube.prototype.evaluate = function(parentContext, inst) {
var context = Context.newContext(parentContext, ["size", "center"], [], inst);

var openjscadArgs = {resolution:Globals.DEFAULT_RESOLUTION};
var isCentered = Context.contextVariableLookup(context, "center", false);
var size = Context.contextVariableLookup(context, "size", 1);

if (size instanceof Array){
  openjscadArgs.radius = [size[0]/2, size[1]/2, size[2]/2];
} else {
  openjscadArgs.radius = [size/2,size/2,size/2];
}

if (isCentered){
  openjscadArgs.centerVector = [0,0,0];
} else {
  openjscadArgs.centerVector = [openjscadArgs.radius[0],openjscadArgs.radius[1],openjscadArgs.radius[2]];
}

return _.template('CSG.cube({center: [<%=String(centerVector)%>],radius: [<%= radius %>], resolution: <%= resolution%>})')(openjscadArgs)
};


function Circle(a){
PrimitiveModule.call(this, a);
};

Circle.prototype.evaluate = function(parentContext, inst){
var context = Context.newContext(parentContext, ["r", "$fn"], [], inst);

var r = Context.contextVariableLookup(context, "r", 1);
var resolution = Context.get_fragments_from_r(r, context);

return _.template('CAG.circle({center: [0,0], radius: <%=r%>, resolution: <%=resolution%>})')({r: r,resolution: resolution})

};


function Square(a){
PrimitiveModule.call(this, a);
};

Square.prototype.evaluate = function(parentContext, inst){
var context = Context.newContext(parentContext, ["size", "center"], [], inst);

var size = Context.contextVariableLookup(context, "size", [0.5,0.5]);
var center = Context.contextVariableLookup(context, "center", false);
var radius = _.isArray(size)? radius = [size[0]/2,size[1]/2] : [size/2,size/2];
var centerPoint = [0,0];
if (!center){
  centerPoint = [size[0]/2, size[1]/2]
}

return _.template('CAG.rectangle({center: [<%=centerPoint%>], radius: [<%=radius%>]})')({centerPoint:centerPoint, radius:radius});
};

function Polygon(a){
PrimitiveModule.call(this, a);
};

Polygon.prototype.evaluate = function(parentContext, inst){
var context = Context.newContext(parentContext, ["points", "paths", "convexity"], [], inst);

var points = Context.contextVariableLookup(context, "points", []);
var paths = Context.contextVariableLookup(context, "paths", []);
var pointsMap = [];

function formatPoints (points){
  return _.map(points, function(x){return _.template("[<%=x%>]")({x:x})});
}

if (_.isEmpty(paths)){
  return _.template('CAG.fromPoints([<%=points%>])')({points:formatPoints(points)});
}

if (paths.length > 1){
  var lines = "";

  _.each(_.first(paths), function(x) {
      pointsMap.push(points[x]);
  });
  lines += _.template('(new CSG.Path2D([<%=points%>],true)).innerToCAG().subtract([')({points:formatPoints(pointsMap)});

  var holes = [];

  _.each(_.tail(paths), function(shape) {
      pointsMap = [];
      _.each(shape, function(x) {
          pointsMap.push(points[x]);
      });
      holes.push(_.template('(new CSG.Path2D([<%=points%>],true)).innerToCAG()')({points:formatPoints(pointsMap)}));
  });

  lines += holes.join(',') + "])";

  return lines;

} else {
  _.each(paths[0], function(x) {
      pointsMap.push(points[x]);
  });
  return _.template('(new CSG.Path2D([<%=points%>],true)).innerToCAG()')({points:formatPoints(pointsMap)});
}
};

function Polyhedron(a){
	PrimitiveModule.call(this, a);
};

Polyhedron.prototype.evaluate = function(parentContext, inst){
var context = Context.newContext(parentContext, ["points", "triangles", "convexity"], [], inst);

var points = Context.contextVariableLookup(context, "points", []);
var triangles = Context.contextVariableLookup(context, "triangles", []);

var polygons=[];

_.each(triangles, function(triangle) {
  polygons.push(
      _.template("new CSG.Polygon([new CSG.Vertex(new CSG.Vector3D([<%=vec1%>])),new CSG.Vertex(new CSG.Vector3D([<%=vec2%>])),new CSG.Vertex(new CSG.Vector3D([<%=vec3%>]))])")
          ({vec1:points[triangle[2]],
          vec2:points[triangle[1]],
          vec3:points[triangle[0]]}));
});

return _.template("CSG.fromPolygons([<%=polygons%>])")({polygons:polygons});
};



module.exports =  {
	Sphere: Sphere,
	Cube: Cube,
	Cylinder: Cylinder,
	Circle: Circle,
	Square: Square,
	Polygon: Polygon,
	Polyhedron: Polyhedron
}

},{"./Context":15,"./Globals":19,"lodash":2}],28:[function(require,module,exports){
function Range (begin, step, end) {
  this.begin = begin
  this.step = step
  this.end = end
}

module.exports = Range

},{}],29:[function(require,module,exports){
/*
  #	Module:			STL.js
  #
  #	Description:	decode STL 3D file
  #					modified Devon Govett's bmp.js
  #
  #	Reference:
  #		STL specs.	http://en.wikipedia.org/wiki/STL_%28file_format%29#Binary_STL
  # 	BMP.js		http://devongovett.github.com/bmp.js/
  #
  # Author(s):		Devon Govett provide a bmp decoding example.
  # 				C.T. Yeung modify to decode STL.
  #
  # History:
  # 20Dec11			1st crack at it								cty
  # 23Dec11			loading vertexies OK
  # 				need to test normal when rendering shades
  #                 rotation is off when passed 180 degrees		cty
  #
  # MIT LICENSE
  # Copyright (c) 2011 CT Yeung
  # Copyright (c) 2011 Devon Govett
  #
  # Permission is hereby granted, free of charge, to any person obtaining a copy of this
  # software and associated documentation files (the "Software"), to deal in the Software
  # without restriction, including without limitation the rights to use, copy, modify, merge,
  # publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
  # to whom the Software is furnished to do so, subject to the following conditions:
  #
  # The above copyright notice and this permission notice shall be included in all copies or
  # substantial portions of the Software.
  #
  # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
  # BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
  # DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */

	var HDR_LEN = 80;

	function STL(data) {

		var buf = new ArrayBuffer(data.length);
		this.data = new Uint8Array(buf);
		for (var i=0, dataLen=data.length; i<dataLen; i++) {
			this.data[i] = data.charCodeAt(i);
		}

	  	this.TYPE_ASCII = "ascii";
		this.TYPE_BINARY = "binary";
		this.dataType = "";

		this.ASCII_TITLE = "solid";
		this.TYPE_VERTEX = "vertex";
		this.TYPE_NORMAL = "normal";
		this.TYPE_END = "end"
		this.NOT_ASCII = -1;
		this.listVertex = null;
		this.listNormal = null;
		this.pos = 0;

		if(this.data.length<(HDR_LEN+4))
			throw 'STL file too small: ' + this.data.length;
	};

	STL.prototype.findEndPos = function(stt) {
	  var i = stt;
	  while(i<(this.data.length-1)) {
		  // seek linefeed
		  if(this.data[i]==10)
			  return i;
		  i++;
	  }
	  return this.data.length-1;
	};

	STL.prototype.bin2String = function(sttPos, endPos) {
	  var buf="";
	  for(var i=sttPos; i<endPos; i++) {
		  var char = this.data[i].toString();
		  buf += String.fromCharCode(char);
	  }
	  return buf.replace('\r', '');
	};

	STL.prototype.readUInt16 = function() {
		var b1, b2;
		b1 = this.data[this.pos++];
		b2 = this.data[this.pos++] << 8;
		return b1 | b2;
	};

	STL.prototype.readUInt32 = function() {
		var b1, b2, b3, b4;
		b1 = this.data[this.pos++];
		b2 = this.data[this.pos++] << 8;
		b3 = this.data[this.pos++] << 16;
		b4 = this.data[this.pos++] << 24;
		var num = b1 | b2 | b3 | b4;
		return num;
	};

	STL.prototype.readReal32 = function() {
	  if(this.data.length<=this.pos+4)		// over run !!! error condition
		return 0;

	  var byteArray = [0,0,0,0];
	  byteArray[3] = this.data[this.pos++];
	  byteArray[2] = this.data[this.pos++];
	  byteArray[1] = this.data[this.pos++];
	  byteArray[0] = this.data[this.pos++];

	  var sign = this.parseSign(byteArray);
	  var exponent = this.parseExponent(byteArray);
	  var mantissa = this.parseSignificand(byteArray);
	  var num = sign * exponent * mantissa;
	  return num;
	};

	STL.prototype.parseSign = function(byteArray) {
		if(byteArray[0]&0x80)
			return -1;
		return 1;
	};

	STL.prototype.parseExponent = function(byteArray) {
		var ex = (byteArray[0] & 0x7F);
		ex = ex << 1;

		if(0!=(byteArray[1] & 0x80))
			ex += 0x01;

		ex = Math.pow(2, ex-127);
		return ex;
	};

	STL.prototype.parseSignificand = function(byteArray) {
		var num=0;
		var bit;
		var mask = 0x40;
		for(var i=1; i<8; i++) {
			if(0!=(byteArray[1]&mask))
				num += 1 / Math.pow(2, i);
			mask = mask >> 1;
		}
		mask = 0x80;
		for(var j=0; j<8; j++) {
			if(0!=(byteArray[2]&mask))
				num += 1 / Math.pow(2, j+8);
			mask = mask >> 1;
		}
		mask = 0x80;
		for(var k=0; k<8; k++) {
			if(0!=(byteArray[2]&mask))
				num += 1 / Math.pow(2, k+16);
			mask = mask >> 1;
		}
		return (num+1);
	};

	STL.prototype.readNormal = function(index) {
		var sttPos = this.listNormal[index];
	  var endPos = this.findEndPos(sttPos);		// return EOF pos if not found
	  var vString = this.bin2String(sttPos, endPos);
	  var pos = vString.indexOf(this.TYPE_NORMAL);
	  vString = vString.substring(pos+this.TYPE_NORMAL.length+1, vString.length)
	  var list = vString.split(" ");

	  var normal = new Array();
	  for(var i=0; i<list.length; i++) {
		if(list[i].length)
			normal.push(Number(list[i]));
	  }

	  if(list.length<3)
		  return null;							// invalid normal

		return normal;
	};

	STL.prototype.readVertex = function(index) {
		var sttPos = this.listVertex[index];
	  var endPos = this.findEndPos(sttPos);		// return EOF pos if not found
	  var vString = this.bin2String(sttPos, endPos);
	  var pos = vString.indexOf(this.TYPE_VERTEX);
	  vString = vString.substring(pos+this.TYPE_VERTEX.length+1, vString.length);
	  var list = vString.split(" ");

	  var vertex = new Array();
	  for(var i=0; i<list.length; i++) {
		if(list[i].length)
			vertex.push(Number(list[i]));
	  }
	  if(vertex.length!=3)
		  return null;							// invalid vertex

		return vertex;
	};

	STL.prototype.decode = function() {
		if(this.dataType.length) {
			return this.dataType;
		}

		var str = this.bin2String(0, 10).toLocaleLowerCase();
		var endPos = 0;
		var sttPos = 0;

		if(str.indexOf(this.ASCII_TITLE)>=0) {
			this.dataType = this.TYPE_ASCII;
			this.listVertex = new Array();
			this.listNormal = new Array();

			while(endPos < (this.data.length-1)) {
				endPos = this.findEndPos(sttPos);		// return EOF pos if not found
				str = this.bin2String(sttPos, endPos);

				if(str.indexOf(this.TYPE_VERTEX)>=0) {
					this.listVertex.push(sttPos);
				} else if(str.indexOf(this.TYPE_NORMAL)>=0) {
					this.listNormal.push(sttPos);
				}

				sttPos = endPos+1;
			}
		} else {
			this.dataType = this.TYPE_BINARY;
		}

		return this.dataType;
	};

	STL.prototype.getCSG = function(){

		var csgPolygons = [];
		var numTriangles;

		if (this.dataType==this.TYPE_BINARY){
			this.pos = HDR_LEN;
			numTriangles = this.readUInt32();
		} else {
			this.pos = 0;
			numTriangles = this.listVertex.length/3;
		}

		if (this.dataType==this.TYPE_BINARY) {
			for (i=0; i<numTriangles; i++) {

				var csgVertices = [];

				var normal = [0,0,0];
				for(var j=0; j<3; j++) {
					normal[j] = this.readReal32();
				}

				var csgNormal = new CSG.Vector3D(normal);
				var csgPlane = new CSG.Plane(csgNormal, 1);

				for(var j=0; j<3; j++) {
					var x = this.readReal32();
					var y = this.readReal32();
					var z = this.readReal32();
					csgVertices.push(new CSG.Vertex(new CSG.Vector3D(x,y,z)));
				}

				this.pos += 2;

				csgPolygons.push(new CSG.Polygon(csgVertices, null, csgPlane));
			}
		} else {

			for (i=0; i<numTriangles; i++) {
				var csgVertices = [];
				for(var j=0; j<3; j++) {
					var vtx = this.readVertex(i*3+j)
					csgVertices.push(new CSG.Vertex(new CSG.Vector3D(vtx)));
				}
				csgPolygons.push(new CSG.Polygon(csgVertices, null));
			}



		}

		return CSG.fromPolygons(csgPolygons);
	};

	STL.prototype.getCSGString = function(){

		var csgPolygons = [];
		var numTriangles;

		if (this.dataType==this.TYPE_BINARY){
			this.pos = HDR_LEN;
			numTriangles = this.readUInt32();
		} else {
			this.pos = 0;
			numTriangles = this.listVertex.length/3;
		}

		if (this.dataType==this.TYPE_BINARY) {
			for (i=0; i<numTriangles; i++) {

				var csgVertices = [];

				var normal = [0,0,0];
				for(var j=0; j<3; j++) {
					normal[j] = this.readReal32();
				}

				var csgPlane = _.template("new CSG.Plane(new CSG.Vector3D([<%=normal%>]), 1)")({normal: normal});

				for(var j=0; j<3; j++) {
					var x = this.readReal32();
					var y = this.readReal32();
					var z = this.readReal32();
					csgVertices.push(_.template("new CSG.Vertex(new CSG.Vector3D([<%=vertex%>]))")({vertex:[x,y,z]}));
				}
				this.pos += 2;

				csgPolygons.push(_.template("new CSG.Polygon([<%=vertices%>], null)")({vertices:csgVertices}));
			}
		} else {

			for (i=0; i<numTriangles; i++) {
				var csgVertices = [];
				for(var j=0; j<3; j++) {
					var vertex = this.readVertex(i*3+j)
					csgVertices.push(_.template("new CSG.Vertex(new CSG.Vector3D([<%=vertex%>]))")({vertex:vertex}));
				}
				csgPolygons.push(_.template("new CSG.Polygon([<%=vertices%>], null)")({vertices:csgVertices}));
			}

		}

		return _.template("CSG.fromPolygons([<%=polygons%>])")({polygons:csgPolygons});
	};

	STL.prototype.drawWireFrame = function(context,		// [in] canvas context
										   w, 			// [in] canvas width
										   h, 			// [in] canvas height
										   mag,			// [in] magnification
										   rX,
										   rY,
										   rZ) {
		var numTriangles;
		var i;

		if (this.dataType==this.TYPE_BINARY){
			this.pos = HDR_LEN;
			numTriangles = this.readUInt32();
		} else {
			numTriangles = this.listVertex.length/3;
		}

		if (this.dataType==this.TYPE_BINARY) {
			for (i=0; i<numTriangles; i++) {
				// retrieve normal
				var normal = [0,0,0];
				for(var j=0; j<3; j++) {
					normal[j] = this.readReal32();
				}

				this.drawTriangles(context, w, h, mag, rX, rY, rZ);

				//var attr = this.readUInt16();				// retrieve attribute
				this.pos += 2;
			}
		} else {
			for (i=0; i<numTriangles; i++) {
				this.triangleIndex = i;
				this.drawTriangles(context, w, h, mag, rX, rY, rZ);
			}
		}
	};

	STL.prototype.drawTriangles = function(context,		// [in] canvas context
											w, 		// [in] canvas width
											h, 		// [in] canvas height
											mag,		// [in] magnification
											rX,		// [in] amount of rotation X
											rY,		// [in] amount of rotation Y
											rZ){		// [in] amount of rotation Z

		var vtx0 = [0,0,0];
		var vtx1 = [0,0,0];
		var offX = w/2;
		var offY = h/2;
		context.beginPath();

		// convert rotation from degrees to radian
		var radX = Math.PI / 180.0 * rX;
		var radY = Math.PI / 180.0 * rY;
		var radZ = Math.PI / 180.0 * rZ;

		for(var j=0; j<3; j++) {

			if (this.dataType==this.TYPE_ASCII){
				vtx1 = this.readVertex(this.triangleIndex*3+j)
			} else {
				vtx1[0] = this.readReal32();
				vtx1[1] = this.readReal32();
				vtx1[2] = this.readReal32();
			}

			//vtx1[0] = vtx1[0];
			var y = vtx1[1];
			var z = vtx1[2];
			vtx1[1] = Math.cos(radX)*y-Math.sin(radX)*z;
			vtx1[2] = Math.sin(radX)*y+Math.cos(radX)*z

			var x = vtx1[0];
			z = vtx1[2];
			vtx1[0] = Math.cos(radY)*x+Math.sin(radY)*z;
			//vtx1[1] = vtx1[1];
			vtx1[2] = -Math.sin(radY)*x+Math.cos(radY)*z;

			// draw 2 lengths of a triangle
			if (j==0) {
				context.moveTo(vtx1[0]*mag+ offX, vtx1[1]*mag+ offY);		      // move to 1st triangle corner
				vtx0[0] = vtx1[0];
				vtx0[1] = vtx1[1];
				vtx0[2] = vtx1[2];
			} else {
				context.lineTo(vtx1[0]*mag+ offX, vtx1[1]*mag+ offY);
			}

		}
		// complete triangle
		context.lineTo(vtx0[0]*mag+ offX, vtx0[1]*mag+ offY);
		// render on canvase
		context.stroke();
		context.closePath();
	};

	module.exports =  STL

},{}],30:[function(require,module,exports){
var _ = require('lodash')
var Context = require('./Context')
var Globals = require('./Globals')

function TransformModule (factory) {
  var factory = factory

  this.transformChildren = function (children, context, cb) {
    var childModules = []

    for (var i = 0; i < children.length; i++) {
      var childInst = children[i]
      childInst.argvalues = []

      _.each(childInst.argexpr, function (expr, index, list) {
        childInst.argvalues.push(expr.evaluate(context))
      })
      var childAdaptor = factory.getAdaptor(childInst)
      var transformedChild = childAdaptor.evaluate(context, childInst)
      if (transformedChild) {
        transformedChild += cb()
        childModules.push(transformedChild)
      }
    }

    if (childModules.length == 1) {
      return childModules[0]
    } else if (childModules.length > 1) {
      return _.first(childModules) + '.union([' + _.tail(childModules) + '])'
    }
  }
}

function ColorTransform (a) {
  TransformModule.call(this, a)
}

ColorTransform.prototype.evaluate = function (parentContext, inst) {
  inst.argvalues = []

  _.each(inst.argexpr, function (expr, index, list) {
    inst.argvalues.push(expr.evaluate(parentContext))
  })

  var context = Context.newContext(parentContext, ['c', 'alpha'], [], inst)

  var c = Context.contextVariableLookup(context, 'c', undefined)
  var color = 'white'
  if (c !== undefined) {
    color = _.isString(c) ? colorNameLookup[Globals.stripString(c.toLowerCase())] : c
  }

  var alpha = Context.contextVariableLookup(context, 'alpha', undefined)
  if (alpha !== undefined) {
    color[3] = alpha
  }

  return this.transformChildren(inst.children, context, function () {
    return _.template('.setColor(<%=color%>)')({color: color})
  })
}

function MirrorTransform (a) {
  TransformModule.call(this, a)
}

MirrorTransform.prototype.evaluate = function (parentContext, inst) {
  inst.argvalues = []

  _.each(inst.argexpr, function (expr, index, list) {
    inst.argvalues.push(expr.evaluate(parentContext))
  })

  var context = Context.newContext(parentContext, ['v'], [], inst)

  var v = Context.contextVariableLookup(context, 'v', [0, 0, 0])

  if (!(v instanceof Array)) {
    var val = v
    v = [val, val, val]
  }

  return this.transformChildren(inst.children, context, function () {
    return _.template('.mirrored(CSG.Plane.fromNormalAndPoint([<%=v%>], [0,0,0]))')({v: v})
  })
}

function RotateTransform (a) {
  TransformModule.call(this, a)
}

RotateTransform.prototype.evaluate = function (parentContext, inst) {
  inst.argvalues = []

  _.each(inst.argexpr, function (expr, index, list) {
    inst.argvalues.push(expr.evaluate(parentContext))
  })

  var context = Context.newContext(parentContext, ['a', 'v'], [], inst)

  var a = Context.contextVariableLookup(context, 'a', undefined)

  if (_.isArray(a)) {
    return this.transformChildren(inst.children, context, function () {
      return _.template('.rotateX(<%=degreeX%>).rotateY(<%=degreeY%>).rotateZ(<%=degreeZ%>)')
      ({degreeX: a[0],degreeY: a[1],degreeZ: a[2]})
    })
  } else {
    var v = Context.contextVariableLookup(context, 'v', undefined)
    return this.transformChildren(inst.children, context, function () {
      if (v === undefined || v.toString() == '0,0,0') {
        v = [0, 0, 1]
      }
      return _.template('.transform(CSG.Matrix4x4.rotation([0,0,0], [<%=vector%>], <%=degree%>))')({degree: a, vector: v})
    })
  }
}

function ScaleTransform (a) {
  TransformModule.call(this, a)
}

ScaleTransform.prototype.evaluate = function (parentContext, inst) {
  inst.argvalues = []

  _.each(inst.argexpr, function (expr, index, list) {
    inst.argvalues.push(expr.evaluate(parentContext))
  })

  var context = Context.newContext(parentContext, ['v'], [], inst)

  var v = Context.contextVariableLookup(context, 'v', [0, 0, 0])

  if (!(v instanceof Array)) {
    var val = v
    v = [val, val, val]
  }

  return this.transformChildren(inst.children, context, function () {
    return _.template('.scale([<%=v%>])')({v: v})
  })
}

function TranslateTransform (a) {
  TransformModule.call(this, a)
}

TranslateTransform.prototype.evaluate = function (parentContext, inst) {
  inst.argvalues = []

  _.each(inst.argexpr, function (expr, index, list) {
    inst.argvalues.push(expr.evaluate(parentContext))
  })

  var context = Context.newContext(parentContext, ['v'], [], inst)

  var v = Context.contextVariableLookup(context, 'v', [0, 0, 0])

  return this.transformChildren(inst.children, context, function () {
    return _.template('.translate([<%=v%>])')({v: v})
  })
}

function RenderModule (a) {
  TransformModule.call(this, a)
}

RenderModule.prototype.evaluate = function (parentContext, inst) {
  inst.argvalues = []

  _.each(inst.argexpr, function (expr, index, list) {
    inst.argvalues.push(expr.evaluate(parentContext))
  })

  var context = Context.newContext(parentContext, [], [], inst)

  var childIndex = 0
  if (inst.argvalues[0] !== undefined) {
    childIndex = inst.argvalues[0]
  }

  return this.transformChildren(inst.children, context, function () {
    return ''
  })
}

function MultimatrixTransform (a) {
  TransformModule.call(this, a)

  this.transposeMatrix = function (m) {
    var t = []
    var ti = 0

    for (var j in _.range(4)) {
      for (var i in _.range(4)) {
        t[ti++] = m[i][j]
      }
    }
    return t
  }
}

MultimatrixTransform.prototype.evaluate = function (parentContext, inst) {
  inst.argvalues = []

  _.each(inst.argexpr, function (expr, index, list) {
    inst.argvalues.push(expr.evaluate(parentContext))
  })

  var context = Context.newContext(parentContext, ['m'], [], inst)

  var m = Context.contextVariableLookup(context, 'm', undefined)

  var matrix
  if (m !== undefined) {
    matrix = this.transposeMatrix(m)
  }

  return this.transformChildren(inst.children, context, function () {
    return _.template('.transform(new CSG.Matrix4x4( [<%= matrix %>] ))')({matrix: matrix})
  })
}

function ExtrudeTransform (a) {
  TransformModule.call(this, a)
}

ExtrudeTransform.prototype.evaluate = function (parentContext, inst) {
  inst.argvalues = []

  _.each(inst.argexpr, function (expr, index, list) {
    inst.argvalues.push(expr.evaluate(parentContext))
  })

  var context = Context.newContext(parentContext, ['file', 'layer', 'height', 'origin', 'scale', 'center', 'twist', 'slices', '$fn', '$fs', '$fa'], [], inst)

  var height = Context.contextVariableLookup(context, 'height', 100)
  var center = Context.contextVariableLookup(context, 'center', false)
  var twist = Number(Context.contextVariableLookup(context, 'twist', 0)) / -1 // note inverse for openjscad
  var slices = Context.contextVariableLookup(context, 'slices', undefined)
  var fn = Context.contextVariableLookup(context, '$fn', Globals.FN_DEFAULT)
  var fs = Context.contextVariableLookup(context, '$fs', Globals.FS_DEFAULT)
  var fa = Context.contextVariableLookup(context, '$fa', Globals.FA_DEFAULT)

  if (slices === undefined) {
    slices = parseInt(Math.max(2, Math.abs(Context.get_fragments_from_r(height, context) * twist / 360)))
  }

  return this.transformChildren(inst.children, context, function () {
    var template = _.template('.extrude({offset: [0, 0, <%=height%>], twistangle: <%=twist%>,twiststeps: <%=slices%>})')
      ({height: height, twist: twist, slices: slices})
    if (center) {
      var offset = -height / 2
      template += _.template('.translate([0,0,<%=offset%>])')({offset: offset})
    }
    return template
  })
}

var colorNameLookup = {'indianred': [0.804, 0.361, 0.361], 'lightcoral': [0.941, 0.502, 0.502], 'salmon': [0.980, 0.502, 0.447], 'darksalmon': [0.914, 0.588, 0.478], 'lightsalmon': [1, 0.627, 0.478], 'red': [1, 0, 0], 'crimson': [0.863, 0.078, 0.235], 'firebrick': [0.698, 0.133, 0.133], 'darkred': [0.545, 0, 0], 'pink': [1, 0.753, 0.796], 'lightpink': [1, 0.714, 0.757], 'hotpink': [1, 0.412, 0.706], 'deeppink': [1, 0.078, 0.576], 'mediumvioletred': [0.780, 0.082, 0.522], 'palevioletred': [0.859, 0.439, 0.576], 'lightsalmon': [1, 0.627, 0.478], 'coral': [1, 0.498, 0.314], 'tomato': [1, 0.388, 0.278], 'orangered': [1, 0.271, 0], 'darkorange': [1, 0.549, 0], 'orange': [1, 0.647, 0], 'gold': [1, 0.843, 0], 'yellow': [1, 1, 0], 'lightyellow': [1, 1, 0.878], 'lemonchiffon': [1, 0.980, 0.804], 'lightgoldenrodyellow': [0.980, 0.980, 0.824], 'papayawhip': [1, 0.937, 0.835], 'moccasin': [1, 0.894, 0.710], 'peachpuff': [1, 0.855, 0.725], 'palegoldenrod': [0.933, 0.910, 0.667], 'khaki': [0.941, 0.902, 0.549], 'darkkhaki': [0.741, 0.718, 0.420], 'lavender': [0.902, 0.902, 0.980], 'thistle': [0.847, 0.749, 0.847], 'plum': [0.867, 0.627, 0.867], 'violet': [0.933, 0.510, 0.933], 'orchid': [0.855, 0.439, 0.839], 'fuchsia': [1, 0, 1], 'magenta': [1, 0, 1], 'mediumorchid': [0.729, 0.333, 0.827], 'mediumpurple': [0.576, 0.439, 0.859], 'blueviolet': [0.541, 0.169, 0.886], 'darkviolet': [0.580, 0, 0.827], 'darkorchid': [0.600, 0.196, 0.800], 'darkmagenta': [0.545, 0, 0.545], 'purple': [0.502, 0, 0.502], 'indigo': [0.294, 0, 0.510], 'darkslateblue': [0.282, 0.239, 0.545], 'slateblue': [0.416, 0.353, 0.804], 'mediumslateblue': [0.482, 0.408, 0.933], 'greenyellow': [0.678, 1, 0.184], 'chartreuse': [0.498, 1, 0], 'lawngreen': [0.486, 0.988, 0], 'lime': [0, 1, 0], 'limegreen': [0.196, 0.804, 0.196], 'palegreen': [0.596, 0.984, 0.596], 'lightgreen': [0.565, 0.933, 0.565], 'mediumspringgreen': [0, 0.980, 0.604], 'springgreen': [0, 1, 0.498], 'mediumseagreen': [0.235, 0.702, 0.443], 'seagreen': [0.180, 0.545, 0.341], 'forestgreen': [0.133, 0.545, 0.133], 'green': [0, 0.502, 0], 'darkgreen': [0, 0.392, 0], 'yellowgreen': [0.604, 0.804, 0.196], 'olivedrab': [0.420, 0.557, 0.137], 'olive': [0.502, 0.502, 0], 'darkolivegreen': [0.333, 0.420, 0.184], 'mediumaquamarine': [0.400, 0.804, 0.667], 'darkseagreen': [0.561, 0.737, 0.561], 'lightseagreen': [0.125, 0.698, 0.667], 'darkcyan': [0, 0.545, 0.545], 'teal': [0, 0.502, 0.502], 'aqua': [0, 1, 1], 'cyan': [0, 1, 1], 'lightcyan': [0.878, 1, 1], 'paleturquoise': [0.686, 0.933, 0.933], 'aquamarine': [0.498, 1, 0.831], 'turquoise': [0.251, 0.878, 0.816], 'mediumturquoise': [0.282, 0.820, 0.800], 'darkturquoise': [0, 0.808, 0.820], 'cadetblue': [0.373, 0.620, 0.627], 'steelblue': [0.275, 0.510, 0.706], 'lightsteelblue': [0.690, 0.769, 0.871], 'powderblue': [0.690, 0.878, 0.902], 'lightblue': [0.678, 0.847, 0.902], 'skyblue': [0.529, 0.808, 0.922], 'lightskyblue': [0.529, 0.808, 0.980], 'deepskyblue': [0, 0.749, 1], 'dodgerblue': [0.118, 0.565, 1], 'cornflowerblue': [0.392, 0.584, 0.929], 'royalblue': [0.255, 0.412, 0.882], 'blue': [0, 0, 1], 'mediumblue': [0, 0, 0.804], 'darkblue': [0, 0, 0.545], 'navy': [0, 0, 0.502], 'midnightblue': [0.098, 0.098, 0.439], 'cornsilk': [1, 0.973, 0.863], 'blanchedalmond': [1, 0.922, 0.804], 'bisque': [1, 0.894, 0.769], 'navajowhite': [1, 0.871, 0.678], 'wheat': [0.961, 0.871, 0.702], 'burlywood': [0.871, 0.722, 0.529], 'tan': [0.824, 0.706, 0.549], 'rosybrown': [0.737, 0.561, 0.561], 'sandybrown': [0.957, 0.643, 0.376], 'goldenrod': [0.855, 0.647, 0.125], 'darkgoldenrod': [0.722, 0.525, 0.043], 'peru': [0.804, 0.522, 0.247], 'chocolate': [0.824, 0.412, 0.118], 'saddlebrown': [0.545, 0.271, 0.075], 'sienna': [0.627, 0.322, 0.176], 'brown': [0.647, 0.165, 0.165], 'maroon': [0.502, 0, 0], 'white': [1, 1, 1], 'snow': [1, 0.980, 0.980], 'honeydew': [0.941, 1, 0.941], 'mintcream': [0.961, 1, 0.980], 'azure': [0.941, 1, 1], 'aliceblue': [0.941, 0.973, 1], 'ghostwhite': [0.973, 0.973, 1], 'whitesmoke': [0.961, 0.961, 0.961], 'seashell': [1, 0.961, 0.933], 'beige': [0.961, 0.961, 0.863], 'oldlace': [0.992, 0.961, 0.902], 'floralwhite': [1, 0.980, 0.941], 'ivory': [1, 1, 0.941], 'antiquewhite': [0.980, 0.922, 0.843], 'linen': [0.980, 0.941, 0.902], 'lavenderblush': [1, 0.941, 0.961], 'mistyrose': [1, 0.894, 0.882], 'gainsboro': [0.863, 0.863, 0.863], 'lightgrey': [0.827, 0.827, 0.827], 'silver': [0.753, 0.753, 0.753], 'darkgray': [0.663, 0.663, 0.663], 'gray': [0.502, 0.502, 0.502], 'dimgray': [0.412, 0.412, 0.412], 'lightslategray': [0.467, 0.533, 0.600], 'slategray': [0.439, 0.502, 0.565], 'darkslategray': [0.184, 0.310, 0.310], 'black': [0, 0, 0]}

module.exports = {
  Translate: TranslateTransform,
  Scale: ScaleTransform,
  Rotate: RotateTransform,
  Mirror: MirrorTransform,
  Color: ColorTransform,
  Render: RenderModule,
  Multimatrix: MultimatrixTransform,
  Extrude: ExtrudeTransform
}

},{"./Context":15,"./Globals":19,"lodash":2}],31:[function(require,module,exports){
var _ = require('lodash')
var Module = require('./Module')
var Context = require('./Context')
var Globals = require('./Globals')
var FunctionDef = require('./FunctionDef')
var support = require('./openscad-parser-support')

var currmodule = new Module("root");

function resetModule() {
    currmodule = new Module("root");
    Globals.context_stack = [];
    Globals.module_stack = [];
}

function processModule(yy){
    var lines = [];
    lines.push("function main(){");
    lines.push("\n");

    var context = undefined;
    if (yy.context !== undefined){
        context = yy.context;
    } else {
        context = new Context();
    }

    if (yy.importCache !== undefined){
        context.setVariable("importCache", yy.importCache);
    }

    var res = currmodule.evaluate(context);

    var evaluatedLines = _.flatten(res);
    if (evaluatedLines.length == 1){
        lines.push("return "+evaluatedLines[0] + ';');
    } else if (evaluatedLines.length > 1){
        lines.push("return "+_.first(evaluatedLines)+".union([");
        lines.push(_.tail(evaluatedLines));
        lines.push("]);");
    }
    lines.push("};");

    var x = {lines:lines, context:Globals.context_stack[Globals.context_stack.length-1]};
    resetModule();

    return x;
}

function stashModule(newName, newArgNames, newArgExpr){

    var p_currmodule = currmodule;
    Globals.module_stack.push(currmodule);

    currmodule = new Module(newName);

    p_currmodule.modules.push(currmodule);

    currmodule.argnames = newArgNames;
    currmodule.argexpr = newArgExpr;
}

function popModule(){
    if (Globals.module_stack.length > 0){
        currmodule = Globals.module_stack.pop();
    }
}

function addModuleChild(child){
    currmodule.children.push(child);
}

function addModuleAssignmentVar(name, value){
    currmodule.assignments_var[name] = value;
}

function addModuleFunction(name, expr, argnames, argexpr){
    var func = new FunctionDef();
    func.argnames = argnames;
    func.argexpr = argexpr;
    func.expr = expr;
    currmodule.functions[name] = func;
}


module.exports = {
   processModule: processModule,
   stashModule: stashModule,
   popModule: popModule,
   addModuleChild: addModuleChild,
   addModuleAssignmentVar: addModuleAssignmentVar,
   addModuleFunction: addModuleFunction
}

},{"./Context":15,"./FunctionDef":18,"./Globals":19,"./Module":22,"./openscad-parser-support":32,"lodash":2}],32:[function(require,module,exports){

// seedrandom.js version 2.0.
// Author: David Bau 4/2/2011
//
// Defines a method Math.seedrandom() that, when called, substitutes
// an explicitly seeded RC4-based algorithm for Math.random().  Also
// supports automatic seeding from local or network sources of entropy.
//
// Usage:
//
//   <script src=http://davidbau.com/encode/seedrandom-min.js></script>
//
//   Math.seedrandom('yipee'); Sets Math.random to a function that is
//                             initialized using the given explicit seed.
//
//   Math.seedrandom();        Sets Math.random to a function that is
//                             seeded using the current time, dom state,
//                             and other accumulated local entropy.
//                             The generated seed string is returned.
//
//   Math.seedrandom('yowza', true);
//                             Seeds using the given explicit seed mixed
//                             together with accumulated entropy.
//
//   <script src="http://bit.ly/srandom-512"></script>
//                             Seeds using physical random bits downloaded
//                             from random.org.
//
//   <script src="https://jsonlib.appspot.com/urandom?callback=Math.seedrandom">
//   </script>                 Seeds using urandom bits from call.jsonlib.com,
//                             which is faster than random.org.
//
// Examples:
//
//   Math.seedrandom("hello");            // Use "hello" as the seed.
//   document.write(Math.random());       // Always 0.5463663768140734
//   document.write(Math.random());       // Always 0.43973793770592234
//   var rng1 = Math.random;              // Remember the current prng.
//
//   var autoseed = Math.seedrandom();    // New prng with an automatic seed.
//   document.write(Math.random());       // Pretty much unpredictable.
//
//   Math.random = rng1;                  // Continue "hello" prng sequence.
//   document.write(Math.random());       // Always 0.554769432473455
//
//   Math.seedrandom(autoseed);           // Restart at the previous seed.
//   document.write(Math.random());       // Repeat the 'unpredictable' value.
//
// Notes:
//
// Each time seedrandom('arg') is called, entropy from the passed seed
// is accumulated in a pool to help generate future seeds for the
// zero-argument form of Math.seedrandom, so entropy can be injected over
// time by calling seedrandom with explicit data repeatedly.
//
// On speed - This javascript implementation of Math.random() is about
// 3-10x slower than the built-in Math.random() because it is not native
// code, but this is typically fast enough anyway.  Seeding is more expensive,
// especially if you use auto-seeding.  Some details (timings on Chrome 4):
//
// Our Math.random()            - avg less than 0.002 milliseconds per call
// seedrandom('explicit')       - avg less than 0.5 milliseconds per call
// seedrandom('explicit', true) - avg less than 2 milliseconds per call
// seedrandom()                 - avg about 38 milliseconds per call
//
// LICENSE (BSD):
//
// Copyright 2010 David Bau, all rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
// 
//   1. Redistributions of source code must retain the above copyright
//      notice, this list of conditions and the following disclaimer.
//
//   2. Redistributions in binary form must reproduce the above copyright
//      notice, this list of conditions and the following disclaimer in the
//      documentation and/or other materials provided with the distribution.
// 
//   3. Neither the name of this module nor the names of its contributors may
//      be used to endorse or promote products derived from this software
//      without specific prior written permission.
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
/**
 * All code is in an anonymous closure to keep the global namespace clean.
 *
 * @param {number=} overflow 
 * @param {number=} startdenom
 */
(function (pool, math, width, chunks, significance, overflow, startdenom) {


//
// seedrandom()
// This is the seedrandom function described above.
//
math['seedrandom'] = function seedrandom(seed, use_entropy) {
  var key = [];
  var arc4;

  // Flatten the seed string or build one from local entropy if needed.
  seed = mixkey(flatten(
    use_entropy ? [seed, pool] :
    arguments.length ? seed :
    [new Date().getTime(), pool, window], 3), key);

  // Use the seed to initialize an ARC4 generator.
  arc4 = new ARC4(key);

  // Mix the randomness into accumulated entropy.
  mixkey(arc4.S, pool);

  // Override Math.random

  // This function returns a random double in [0, 1) that contains
  // randomness in every bit of the mantissa of the IEEE 754 value.

  math['random'] = function random() {  // Closure to return a random double:
    var n = arc4.g(chunks);             // Start with a numerator n < 2 ^ 48
    var d = startdenom;                 //   and denominator d = 2 ^ 48.
    var x = 0;                          //   and no 'extra last byte'.
    while (n < significance) {          // Fill up all significant digits by
      n = (n + x) * width;              //   shifting numerator and
      d *= width;                       //   denominator and generating a
      x = arc4.g(1);                    //   new least-significant-byte.
    }
    while (n >= overflow) {             // To avoid rounding up, before adding
      n /= 2;                           //   last byte, shift everything
      d /= 2;                           //   right using integer math until
      x >>>= 1;                         //   we have exactly the desired bits.
    }
    return (n + x) / d;                 // Form the number within [0, 1).
  };

  // Return the seed that was used
  return seed;
};

//
// ARC4
//
// An ARC4 implementation.  The constructor takes a key in the form of
// an array of at most (width) integers that should be 0 <= x < (width).
//
// The g(count) method returns a pseudorandom integer that concatenates
// the next (count) outputs from ARC4.  Its return value is a number x
// that is in the range 0 <= x < (width ^ count).
//
/** @constructor */
function ARC4(key) {
  var t, u, me = this, keylen = key.length;
  var i = 0, j = me.i = me.j = me.m = 0;
  me.S = [];
  me.c = [];

  // The empty key [] is treated as [0].
  if (!keylen) { key = [keylen++]; }

  // Set up S using the standard key scheduling algorithm.
  while (i < width) { me.S[i] = i++; }
  for (i = 0; i < width; i++) {
    t = me.S[i];
    j = lowbits(j + t + key[i % keylen]);
    u = me.S[j];
    me.S[i] = u;
    me.S[j] = t;
  }

  // The "g" method returns the next (count) outputs as one number.
  me.g = function getnext(count) {
    var s = me.S;
    var i = lowbits(me.i + 1); var t = s[i];
    var j = lowbits(me.j + t); var u = s[j];
    s[i] = u;
    s[j] = t;
    var r = s[lowbits(t + u)];
    while (--count) {
      i = lowbits(i + 1); t = s[i];
      j = lowbits(j + t); u = s[j];
      s[i] = u;
      s[j] = t;
      r = r * width + s[lowbits(t + u)];
    }
    me.i = i;
    me.j = j;
    return r;
  };
  // For robust unpredictability discard an initial batch of values.
  // See http://www.rsa.com/rsalabs/node.asp?id=2009
  me.g(width);
}

//
// flatten()
// Converts an object tree to nested arrays of strings.
//
/** @param {Object=} result 
  * @param {string=} prop
  * @param {string=} typ */
function flatten(obj, depth, result, prop, typ) {
  result = [];
  typ = typeof(obj);
  if (depth && typ == 'object') {
    for (prop in obj) {
      if (prop.indexOf('S') < 5) {    // Avoid FF3 bug (local/sessionStorage)
        try { result.push(flatten(obj[prop], depth - 1)); } catch (e) {}
      }
    }
  }
  return (result.length ? result : obj + (typ != 'string' ? '\0' : ''));
}

//
// mixkey()
// Mixes a string seed into a key that is an array of integers, and
// returns a shortened string seed that is equivalent to the result key.
//
/** @param {number=} smear 
  * @param {number=} j */
function mixkey(seed, key, smear, j) {
  seed += '';                         // Ensure the seed is a string
  smear = 0;
  for (j = 0; j < seed.length; j++) {
    key[lowbits(j)] =
      lowbits((smear ^= key[lowbits(j)] * 19) + seed.charCodeAt(j));
  }
  seed = '';
  for (j in key) { seed += String.fromCharCode(key[j]); }
  return seed;
}

//
// lowbits()
// A quick "n mod width" for width a power of 2.
//
function lowbits(n) { return n & (width - 1); }

//
// The following constants are related to IEEE 754 limits.
//
startdenom = math.pow(width, chunks);
significance = math.pow(2, significance);
overflow = significance * 2;

//
// When seedrandom.js is loaded, we immediately mix a few bits
// from the built-in RNG into the entropy pool.  Because we do
// not want to intefere with determinstic PRNG state later,
// seedrandom will not call math.random on its own again after
// initialization.
//
mixkey(math.random(), pool);

// End anonymous scope, and pass initial values.
})(
  [],   // pool: entropy pool starts empty
  Math, // math: package containing random, pow, and seedrandom
  256,  // width: each RC4 output is 0 <= x < 256
  6,    // chunks: at least six RC4 outputs for each double
  52    // significance: there are 52 significant digits in a double
);

},{}],33:[function(require,module,exports){
(function (process){
const ext = require('./openscad-parser-ext')
const ArgContainer = require('./ArgContainer')
const ArgsContainer = require('./ArgsContainer')
const Expression = require('./Expression')
const ModuleInstantiation = require('./ModuleInstantiation')
const IfElseModuleInstantiation = require('./IfElseModuleInstantiation')
/* parser generated by jison 0.4.17 */
/*
  Returns a Parser object of the following structure:

  Parser: {
    yy: {}
  }

  Parser.prototype: {
    yy: {},
    trace: function(),
    symbols_: {associative list: name ==> number},
    terminals_: {associative list: number ==> name},
    productions_: [...],
    performAction: function anonymous(yytext, yyleng, yylineno, yy, yystate, $$, _$),
    table: [...],
    defaultActions: {...},
    parseError: function(str, hash),
    parse: function(input),

    lexer: {
        EOF: 1,
        parseError: function(str, hash),
        setInput: function(input),
        input: function(),
        unput: function(str),
        more: function(),
        less: function(n),
        pastInput: function(),
        upcomingInput: function(),
        showPosition: function(),
        test_match: function(regex_match_array, rule_index),
        next: function(),
        lex: function(),
        begin: function(condition),
        popState: function(),
        _currentRules: function(),
        topState: function(),
        pushState: function(condition),

        options: {
            ranges: boolean           (optional: true ==> token location info will include a .range[] member)
            flex: boolean             (optional: true ==> flex-like lexing behaviour where the rules are tested exhaustively to find the longest match)
            backtrack_lexer: boolean  (optional: true ==> lexer regexes are tested in order and for each matching regex the action code is invoked; the lexer terminates the scan when a token is returned by the action code)
        },

        performAction: function(yy, yy_, $avoiding_name_collisions, YY_START),
        rules: [...],
        conditions: {associative list: name ==> set},
    }
  }


  token location info (@$, _$, etc.): {
    first_line: n,
    last_line: n,
    first_column: n,
    last_column: n,
    range: [start_number, end_number]       (where the numbers are indexes into the input string, regular zero-based)
  }


  the parseError function receives a 'hash' object with these members for lexer and parser errors: {
    text:        (matched text)
    token:       (the produced terminal token, if any)
    line:        (yylineno)
  }
  while parser (grammar) errors will also provide these members, i.e. parser errors deliver a superset of attributes: {
    loc:         (yylloc)
    expected:    (string describing the set of expected tokens)
    recoverable: (boolean: TRUE when the parser has a error recovery rule available for this particular error)
  }
*/
var parser = (function(){
var o=function(k,v,o,l){for(o=o||{},l=k.length;l--;o[k[l]]=v);return o},$V0=[1,9,10,15,16,21,22,26,31,32,33,34],$V1=[10,15,16,21,22,26,31,32,33,34],$V2=[2,7],$V3=[1,5],$V4=[1,20],$V5=[1,15],$V6=[1,16],$V7=[1,17],$V8=[1,18],$V9=[1,9,10,15,16,17,21,22,26,31,32,33,34],$Va=[9,10,15,16,17,21,22,26,31,32,33,34],$Vb=[1,24],$Vc=[1,30],$Vd=[1,29],$Ve=[1,9,10,15,16,17,21,22,26,28,31,32,33,34],$Vf=[1,44],$Vg=[1,51],$Vh=[1,50],$Vi=[1,41],$Vj=[1,42],$Vk=[1,43],$Vl=[1,45],$Vm=[1,46],$Vn=[1,47],$Vo=[1,48],$Vp=[1,49],$Vq=[14,57],$Vr=[2,70],$Vs=[1,55],$Vt=[10,17,26,31,32,33,34],$Vu=[10,15,16,26,31,32,33,34],$Vv=[2,65],$Vw=[1,62],$Vx=[1,67],$Vy=[1,65],$Vz=[1,64],$VA=[1,79],$VB=[1,66],$VC=[1,68],$VD=[1,69],$VE=[1,70],$VF=[1,71],$VG=[1,72],$VH=[1,73],$VI=[1,74],$VJ=[1,75],$VK=[1,76],$VL=[1,77],$VM=[1,78],$VN=[14,15,33,34,38,41,42,43,45,46,47,48,49,50,51,52,53,54,55,56,57],$VO=[2,33],$VP=[1,80],$VQ=[2,62],$VR=[1,84],$VS=[1,90],$VT=[1,97],$VU=[43,57],$VV=[10,11,14,31,35,36,37,39,40,41,43,46,47],$VW=[14,15,42,43,46,47,48,49,50,51,52,53,54,55,56,57],$VX=[14,15,33,34,42,43,45,46,47,48,49,50,51,52,53,54,55,56,57],$VY=[14,15,42,43,48,49,52,53,54,55,56,57],$VZ=[14,15,42,43,48,49,50,51,52,53,54,55,56,57],$V_=[2,61];
var parser = {trace: function trace() { },
yy: {},
symbols_: {"error":2,"program":3,"input":4,"statement":5,"inner_input":6,"statement_begin":7,"statement_end":8,"TOK_MODULE":9,"TOK_ID":10,"(":11,"arguments_decl":12,"optional_commas":13,")":14,";":15,"{":16,"}":17,"module_instantiation":18,"=":19,"expr":20,"TOK_FUNCTION":21,"BR":22,"children_instantiation":23,"module_instantiation_list":24,"if_statement":25,"TOK_IF":26,"ifelse_statement":27,"TOK_ELSE":28,"single_module_instantiation":29,"arguments_call":30,"!":31,"#":32,"%":33,"*":34,"TOK_TRUE":35,"TOK_FALSE":36,"TOK_UNDEF":37,".":38,"TOK_STRING":39,"TOK_NUMBER":40,"[":41,":":42,"]":43,"vector_expr":44,"/":45,"+":46,"-":47,"<":48,"LE":49,"EQ":50,"NE":51,"GE":52,">":53,"AND":54,"OR":55,"?":56,",":57,"argument_decl":58,"argument_call":59,"$accept":0,"$end":1},
terminals_: {2:"error",9:"TOK_MODULE",10:"TOK_ID",11:"(",14:")",15:";",16:"{",17:"}",19:"=",21:"TOK_FUNCTION",22:"BR",26:"TOK_IF",28:"TOK_ELSE",31:"!",32:"#",33:"%",34:"*",35:"TOK_TRUE",36:"TOK_FALSE",37:"TOK_UNDEF",38:".",39:"TOK_STRING",40:"TOK_NUMBER",41:"[",42:":",43:"]",45:"/",46:"+",47:"-",48:"<",49:"LE",50:"EQ",51:"NE",52:"GE",53:">",54:"AND",55:"OR",56:"?",57:","},
productions_: [0,[3,1],[4,0],[4,2],[6,0],[6,2],[5,2],[7,0],[7,6],[8,1],[8,3],[8,1],[8,4],[8,9],[8,1],[23,1],[23,3],[25,5],[27,1],[27,3],[18,2],[18,2],[18,1],[24,0],[24,2],[29,4],[29,2],[29,2],[29,2],[29,2],[20,1],[20,1],[20,1],[20,1],[20,3],[20,1],[20,1],[20,5],[20,7],[20,3],[20,4],[20,3],[20,3],[20,3],[20,3],[20,3],[20,3],[20,3],[20,3],[20,3],[20,3],[20,3],[20,3],[20,3],[20,2],[20,2],[20,2],[20,3],[20,5],[20,4],[20,4],[13,2],[13,0],[44,1],[44,4],[12,0],[12,1],[12,4],[58,1],[58,3],[30,0],[30,1],[30,4],[59,1],[59,3]],
performAction: function anonymous(yytext, yyleng, yylineno, yy, yystate /* action[1] */, $$ /* vstack */, _$ /* lstack */) {
/* this == yyval */

var $0 = $$.length - 1;
switch (yystate) {
case 1:

            return ext.processModule(yy);
        
break;
case 8:

            ext.stashModule($$[$0-4], $$[$0-2].argnames, $$[$0-2].argexpr);
            delete $$[$0-2];
        
break;
case 9:

        
break;
case 10:

            ext.popModule();
        
break;
case 11:

            ext.addModuleChild($$[$0]);
        
break;
case 12:

            ext.addModuleAssignmentVar($$[$0-3], $$[$0-1]);
        
break;
case 13:

            ext.addModuleFunction($$[$0-7], $$[$0-1], $$[$0-5].argnames, $$[$0-5].argexpr);
            delete $$[$0-5];
        
break;
case 15:

            this.$ = new ModuleInstantiation();
            if ($$[$0]) {
                this.$.children.push($$[$0]);
            }
        
break;
case 16: case 20:

            this.$ = $$[$0-1];
        
break;
case 17:

            this.$ = new IfElseModuleInstantiation();
            this.$.argnames.push("");
            this.$.argexpr.push($$[$0-2]);

            if (this.$) {
                this.$.children = $$[$0].children;
            } else {
                for (var i = 0; i < $$[$0].children.size(); i++)
                    delete $$[$0].children[i];
            }
            delete $$[$0];
        
break;
case 18: case 22: case 54:

            this.$ = $$[$0];
        
break;
case 19:

            this.$ = $$[$0-2];
            if (this.$) {
                this.$.else_children = $$[$0].children;
            } else {
                for (var i = 0; i < $$[$0].children.size(); i++)
                    delete $$[$0].children[i];
            }
            delete $$[$0];
        
break;
case 21:

            this.$ = $$[$0-1];
            if (this.$) {
                this.$.children = $$[$0].children;
            } else {
                for (var i = 0; i < $$[$0].children.length; i++)
                delete $$[$0].children[i];
            }
            delete $$[$0];
        
break;
case 23:

            this.$ = new ModuleInstantiation();
        
break;
case 24:

            this.$ = $$[$0-1];
            if (this.$) {
                if ($$[$0]) {
                    this.$.children.push($$[$0]);
                }
            } else {
                delete $$[$0];
            }
        
break;
case 25:

            this.$ = new ModuleInstantiation();
            this.$.name = $$[$0-3];
            this.$.argnames = $$[$0-1].argnames;
            this.$.argexpr = $$[$0-1].argexpr;
            delete $$[$0-1];
        
break;
case 26:

            this.$ = $$[$0];
            if (this.$) {
                this.$.tag_root = true;
            }
        
break;
case 27:

            this.$ = $$[$0];
            if (this.$) {
                this.$.tag_highlight = true;
            }
        
break;
case 28:

            /* - NOTE: Currently unimplemented, therefore not displaying parts marked with %
                this.$ = $$[$0];
                if (this.$) {
                    this.$.tag_background = true;
                }
            */
            delete $$[$0];
            this.$ = undefined;
        
break;
case 29:

            delete $$[$0];
            this.$ = undefined;
        
break;
case 30:

            this.$ = new Expression(true);
        
break;
case 31:

            this.$ = new Expression(false);
        
break;
case 32:

            this.$ = new Expression(undefined);
        
break;
case 33:

            this.$ = new Expression();
            this.$.type = "L";
            this.$.var_name = $$[$0];
        
break;
case 34:

            this.$ = new Expression();
            this.$.type = "N";
            this.$.children.push($$[$0-2]);
            this.$.var_name = $$[$0];
        
break;
case 35:

            this.$ = new Expression(String($$[$0]));
        
break;
case 36:

            this.$ = new Expression(Number($$[$0]));
        
break;
case 37:

            var e_one = new Expression(1.0);
            this.$ = new Expression();
            this.$.type = "R";
            this.$.children.push($$[$0-3]);
            this.$.children.push(e_one);
            this.$.children.push($$[$0-1]);
        
break;
case 38:

            this.$ = new Expression();
            this.$.type = "R";
            this.$.children.push($$[$0-5]);
            this.$.children.push($$[$0-3]);
            this.$.children.push($$[$0-1]);
        
break;
case 39:

            this.$ = new Expression([]);
        
break;
case 40:

            this.$ = $$[$0-2];
        
break;
case 41:

            this.$ = new Expression();
            this.$.type = '*';
            this.$.children.push($$[$0-2]);
            this.$.children.push($$[$0]);
        
break;
case 42:

            this.$ = new Expression();
            this.$.type = '/';
            this.$.children.push($$[$0-2]);
            this.$.children.push($$[$0]);
        
break;
case 43:

            this.$ = new Expression();
            this.$.type = '%';
            this.$.children.push($$[$0-2]);
            this.$.children.push($$[$0]);
        
break;
case 44:

            this.$ = new Expression();
            this.$.type = '+';
            this.$.children.push($$[$0-2]);
            this.$.children.push($$[$0]);
        
break;
case 45:

            this.$ = new Expression();
            this.$.type = '-';
            this.$.children.push($$[$0-2]);
            this.$.children.push($$[$0]);
        
break;
case 46:

            this.$ = new Expression();
            this.$.type = '<';
            this.$.children.push($$[$0-2]);
            this.$.children.push($$[$0]);
        
break;
case 47:

            this.$ = new Expression();
            this.$.type = '<=';
            this.$.children.push($$[$0-2]);
            this.$.children.push($$[$0]);
        
break;
case 48:

            this.$ = new Expression();
            this.$.type = '==';
            this.$.children.push($$[$0-2]);
            this.$.children.push($$[$0]);
        
break;
case 49:

            this.$ = new Expression();
            this.$.type = '!=';
            this.$.children.push($$[$0-2]);
            this.$.children.push($$[$0]);
        
break;
case 50:

            this.$ = new Expression();
            this.$.type = '>=';
            this.$.children.push($$[$0-2]);
            this.$.children.push($$[$0]);
        
break;
case 51:

            this.$ = new Expression();
            this.$.type = '>';
            this.$.children.push($$[$0-2]);
            this.$.children.push($$[$0]);
        
break;
case 52:

            this.$ = new Expression();
            this.$.type = '&&';
            this.$.children.push($$[$0-2]);
            this.$.children.push($$[$0]);
        
break;
case 53:

            this.$ = new Expression();
            this.$.type = '||';
            this.$.children.push($$[$0-2]);
            this.$.children.push($$[$0]);
        
break;
case 55:

            this.$ = new Expression();
            this.$.type = 'I';
            this.$.children.push($$[$0]);
        
break;
case 56:

            this.$ = new Expression();
            this.$.type = '!';
            this.$.children.push($$[$0]);
        
break;
case 57:
 this.$ = $$[$0-1]; 
break;
case 58:

            this.$ = new Expression();
            this.$.type = '?:';
            this.$.children.push($$[$0-4]);
            this.$.children.push($$[$0-2]);
            this.$.children.push($$[$0]);
        
break;
case 59:

            this.$ = new Expression();
            this.$.type = '[]';
            this.$.children.push($$[$0-3]);
            this.$.children.push($$[$0-1]);
        
break;
case 60:

            this.$ = new Expression();
            this.$.type = 'F';
            this.$.call_funcname = $$[$0-3];
            this.$.call_argnames = $$[$0-1].argnames;
            this.$.children = $$[$0-1].argexpr;
            delete $$[$0-1];
        
break;
case 63:

            this.$ = new Expression();
            this.$.type = 'V';
            this.$.children.push($$[$0]);
        
break;
case 64:

            this.$ = $$[$0-3];
            this.$.children.push($$[$0]);
        
break;
case 65: case 70:

            this.$ = new ArgsContainer();
        
break;
case 66: case 71:

            this.$ = new ArgsContainer();
            this.$.argnames.push($$[$0].argname);
            this.$.argexpr.push($$[$0].argexpr);
            delete $$[$0];
        
break;
case 67: case 72:

            this.$ = $$[$0-3];
            this.$.argnames.push($$[$0].argname);
            this.$.argexpr.push($$[$0].argexpr);
            delete $$[$0];
        
break;
case 68:

            this.$ = new ArgContainer();
            this.$.argname = $$[$0];
            this.$.argexpr = undefined;
        
break;
case 69: case 74:

            this.$ = new ArgContainer();
            this.$.argname = $$[$0-2];
            this.$.argexpr = $$[$0];
        
break;
case 73:

            this.$ = new ArgContainer();
            this.$.argexpr = $$[$0];
        
break;
}
},
table: [o($V0,[2,2],{3:1,4:2}),{1:[3]},o($V1,$V2,{5:3,7:4,1:[2,1],9:$V3}),o($V0,[2,3]),{8:6,10:[1,10],15:[1,7],16:[1,8],18:9,21:[1,11],22:[1,12],25:19,26:$V4,27:14,29:13,31:$V5,32:$V6,33:$V7,34:$V8},{10:[1,21]},o($V9,[2,6]),o($V9,[2,9]),o($Va,[2,4],{6:22}),o($V9,[2,11]),{11:$Vb,19:[1,23]},{10:[1,25]},o($V9,[2,14]),{10:$Vc,15:[1,26],16:$Vd,18:28,23:27,25:19,26:$V4,27:14,29:13,31:$V5,32:$V6,33:$V7,34:$V8},o($Ve,[2,22]),{10:$Vc,29:31,31:$V5,32:$V6,33:$V7,34:$V8},{10:$Vc,29:32,31:$V5,32:$V6,33:$V7,34:$V8},{10:$Vc,29:33,31:$V5,32:$V6,33:$V7,34:$V8},{10:$Vc,29:34,31:$V5,32:$V6,33:$V7,34:$V8},o($V9,[2,18],{28:[1,35]}),{11:[1,36]},{11:[1,37]},o($V1,$V2,{7:4,5:39,9:$V3,17:[1,38]}),{10:$Vf,11:$Vg,20:40,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},o($Vq,$Vr,{30:52,59:53,20:54,10:$Vs,11:$Vg,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp}),{11:[1,56]},o($Ve,[2,20]),o($Ve,[2,21]),o($Ve,[2,15]),o($Vt,[2,23],{24:57}),{11:$Vb},o($Vu,[2,26]),o($Vu,[2,27]),o($Vu,[2,28]),o($Vu,[2,29]),{10:$Vc,16:$Vd,18:28,23:58,25:19,26:$V4,27:14,29:13,31:$V5,32:$V6,33:$V7,34:$V8},{10:$Vf,11:$Vg,20:59,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},o($Vq,$Vv,{12:60,58:61,10:$Vw}),o($V9,[2,10]),o($Va,[2,5]),{15:[1,63],33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB,46:$VC,47:$VD,48:$VE,49:$VF,50:$VG,51:$VH,52:$VI,53:$VJ,54:$VK,55:$VL,56:$VM},o($VN,[2,30]),o($VN,[2,31]),o($VN,[2,32]),o($VN,$VO,{11:$VP}),o($VN,[2,35]),o($VN,[2,36]),{10:$Vf,11:$Vg,13:82,20:81,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,43:$VQ,44:83,46:$Vo,47:$Vp,57:$VR},{10:$Vf,11:$Vg,20:85,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{10:$Vf,11:$Vg,20:86,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{10:$Vf,11:$Vg,20:87,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{10:$Vf,11:$Vg,20:88,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{14:[1,89],57:$VS},o($Vq,[2,71]),o($Vq,[2,73],{33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB,46:$VC,47:$VD,48:$VE,49:$VF,50:$VG,51:$VH,52:$VI,53:$VJ,54:$VK,55:$VL,56:$VM}),o([14,33,34,38,41,45,46,47,48,49,50,51,52,53,54,55,56,57],$VO,{11:$VP,19:[1,91]}),o($Vq,$Vv,{58:61,12:92,10:$Vw}),{10:$Vc,17:[1,93],18:94,25:19,26:$V4,27:14,29:13,31:$V5,32:$V6,33:$V7,34:$V8},o($Ve,[2,19]),{14:[1,95],33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB,46:$VC,47:$VD,48:$VE,49:$VF,50:$VG,51:$VH,52:$VI,53:$VJ,54:$VK,55:$VL,56:$VM},{13:96,14:$VQ,57:$VT},o($Vq,[2,66]),o($Vq,[2,68],{19:[1,98]}),o($V9,[2,12]),{10:[1,99]},{10:$Vf,11:$Vg,20:100,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{10:$Vf,11:$Vg,20:101,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{10:$Vf,11:$Vg,20:102,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{10:$Vf,11:$Vg,20:103,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{10:$Vf,11:$Vg,20:104,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{10:$Vf,11:$Vg,20:105,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{10:$Vf,11:$Vg,20:106,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{10:$Vf,11:$Vg,20:107,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{10:$Vf,11:$Vg,20:108,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{10:$Vf,11:$Vg,20:109,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{10:$Vf,11:$Vg,20:110,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{10:$Vf,11:$Vg,20:111,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{10:$Vf,11:$Vg,20:112,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{10:$Vf,11:$Vg,20:113,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{10:$Vf,11:$Vg,20:114,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},o($Vq,$Vr,{59:53,20:54,30:115,10:$Vs,11:$Vg,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp}),o($VU,[2,63],{33:$Vx,34:$Vy,38:$Vz,41:$VA,42:[1,116],45:$VB,46:$VC,47:$VD,48:$VE,49:$VF,50:$VG,51:$VH,52:$VI,53:$VJ,54:$VK,55:$VL,56:$VM}),{43:[1,117]},{13:118,43:$VQ,57:[1,119]},o($VV,$VQ,{13:120,57:$VR}),o($VW,[2,54],{33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB}),o($VW,[2,55],{33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB}),o($VW,[2,56],{33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB}),{14:[1,121],33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB,46:$VC,47:$VD,48:$VE,49:$VF,50:$VG,51:$VH,52:$VI,53:$VJ,54:$VK,55:$VL,56:$VM},o($Vu,[2,25]),o([10,11,31,35,36,37,39,40,41,46,47],$VQ,{13:122,57:$VR}),{10:$Vf,11:$Vg,20:123,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{13:124,14:$VQ,57:$VT},o($Ve,[2,16]),o($Vt,[2,24]),{10:$Vc,16:$Vd,18:28,23:125,25:19,26:$V4,27:14,29:13,31:$V5,32:$V6,33:$V7,34:$V8},{14:[1,126]},o([10,14],$VQ,{13:127,57:$VR}),{10:$Vf,11:$Vg,20:128,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},o($VN,[2,34]),o($VX,[2,41],{38:$Vz,41:$VA}),o($VX,[2,42],{38:$Vz,41:$VA}),o($VX,[2,43],{38:$Vz,41:$VA}),o($VW,[2,44],{33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB}),o($VW,[2,45],{33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB}),o($VY,[2,46],{33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB,46:$VC,47:$VD,50:$VG,51:$VH}),o($VY,[2,47],{33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB,46:$VC,47:$VD,50:$VG,51:$VH}),o($VZ,[2,48],{33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB,46:$VC,47:$VD}),o($VZ,[2,49],{33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB,46:$VC,47:$VD}),o($VY,[2,50],{33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB,46:$VC,47:$VD,50:$VG,51:$VH}),o($VY,[2,51],{33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB,46:$VC,47:$VD,50:$VG,51:$VH}),o([14,15,42,43,54,55,56,57],[2,52],{33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB,46:$VC,47:$VD,48:$VE,49:$VF,50:$VG,51:$VH,52:$VI,53:$VJ}),o([14,15,42,43,55,56,57],[2,53],{33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB,46:$VC,47:$VD,48:$VE,49:$VF,50:$VG,51:$VH,52:$VI,53:$VJ,54:$VK}),{33:$Vx,34:$Vy,38:$Vz,41:$VA,42:[1,129],45:$VB,46:$VC,47:$VD,48:$VE,49:$VF,50:$VG,51:$VH,52:$VI,53:$VJ,54:$VK,55:$VL,56:$VM},{33:$Vx,34:$Vy,38:$Vz,41:$VA,43:[1,130],45:$VB,46:$VC,47:$VD,48:$VE,49:$VF,50:$VG,51:$VH,52:$VI,53:$VJ,54:$VK,55:$VL,56:$VM},{14:[1,131],57:$VS},{10:$Vf,11:$Vg,20:132,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},o($VN,[2,39]),{43:[1,133]},o([10,11,31,35,36,37,39,40,41,43,46,47],$VQ,{13:134,57:$VR}),o($VV,$V_),o($VN,[2,57]),{10:$Vs,11:$Vg,20:54,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp,59:135},o($Vq,[2,74],{33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB,46:$VC,47:$VD,48:$VE,49:$VF,50:$VG,51:$VH,52:$VI,53:$VJ,54:$VK,55:$VL,56:$VM}),{14:[1,136]},o($Ve,[2,17]),o($V1,[2,8]),{10:$Vw,14:$V_,58:137},o($Vq,[2,69],{33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB,46:$VC,47:$VD,48:$VE,49:$VF,50:$VG,51:$VH,52:$VI,53:$VJ,54:$VK,55:$VL,56:$VM}),{10:$Vf,11:$Vg,20:138,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},o($VN,[2,59]),o($VN,[2,60]),{33:$Vx,34:$Vy,38:$Vz,41:$VA,42:[1,140],43:[1,139],45:$VB,46:$VC,47:$VD,48:$VE,49:$VF,50:$VG,51:$VH,52:$VI,53:$VJ,54:$VK,55:$VL,56:$VM},o($VN,[2,40]),{10:$Vf,11:$Vg,20:141,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,43:$V_,46:$Vo,47:$Vp},o($Vq,[2,72]),{19:[1,142]},o($Vq,[2,67]),o([14,15,42,43,57],[2,58],{33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB,46:$VC,47:$VD,48:$VE,49:$VF,50:$VG,51:$VH,52:$VI,53:$VJ,54:$VK,55:$VL,56:$VM}),o($VN,[2,37]),{10:$Vf,11:$Vg,20:143,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},o($VU,[2,64],{33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB,46:$VC,47:$VD,48:$VE,49:$VF,50:$VG,51:$VH,52:$VI,53:$VJ,54:$VK,55:$VL,56:$VM}),{10:$Vf,11:$Vg,20:144,31:$Vh,35:$Vi,36:$Vj,37:$Vk,39:$Vl,40:$Vm,41:$Vn,46:$Vo,47:$Vp},{33:$Vx,34:$Vy,38:$Vz,41:$VA,43:[1,145],45:$VB,46:$VC,47:$VD,48:$VE,49:$VF,50:$VG,51:$VH,52:$VI,53:$VJ,54:$VK,55:$VL,56:$VM},{15:[1,146],33:$Vx,34:$Vy,38:$Vz,41:$VA,45:$VB,46:$VC,47:$VD,48:$VE,49:$VF,50:$VG,51:$VH,52:$VI,53:$VJ,54:$VK,55:$VL,56:$VM},o($VN,[2,38]),o($V9,[2,13])],
defaultActions: {},
parseError: function parseError(str, hash) {
    if (hash.recoverable) {
        this.trace(str);
    } else {
        function _parseError (msg, hash) {
            this.message = msg;
            this.hash = hash;
        }
        _parseError.prototype = Error;

        throw new _parseError(str, hash);
    }
},
parse: function parse(input) {
    var self = this, stack = [0], tstack = [], vstack = [null], lstack = [], table = this.table, yytext = '', yylineno = 0, yyleng = 0, recovering = 0, TERROR = 2, EOF = 1;
    var args = lstack.slice.call(arguments, 1);
    var lexer = Object.create(this.lexer);
    var sharedState = { yy: {} };
    for (var k in this.yy) {
        if (Object.prototype.hasOwnProperty.call(this.yy, k)) {
            sharedState.yy[k] = this.yy[k];
        }
    }
    lexer.setInput(input, sharedState.yy);
    sharedState.yy.lexer = lexer;
    sharedState.yy.parser = this;
    if (typeof lexer.yylloc == 'undefined') {
        lexer.yylloc = {};
    }
    var yyloc = lexer.yylloc;
    lstack.push(yyloc);
    var ranges = lexer.options && lexer.options.ranges;
    if (typeof sharedState.yy.parseError === 'function') {
        this.parseError = sharedState.yy.parseError;
    } else {
        this.parseError = Object.getPrototypeOf(this).parseError;
    }
    function popStack(n) {
        stack.length = stack.length - 2 * n;
        vstack.length = vstack.length - n;
        lstack.length = lstack.length - n;
    }
    _token_stack:
        var lex = function () {
            var token;
            token = lexer.lex() || EOF;
            if (typeof token !== 'number') {
                token = self.symbols_[token] || token;
            }
            return token;
        };
    var symbol, preErrorSymbol, state, action, a, r, yyval = {}, p, len, newState, expected;
    while (true) {
        state = stack[stack.length - 1];
        if (this.defaultActions[state]) {
            action = this.defaultActions[state];
        } else {
            if (symbol === null || typeof symbol == 'undefined') {
                symbol = lex();
            }
            action = table[state] && table[state][symbol];
        }
                    if (typeof action === 'undefined' || !action.length || !action[0]) {
                var errStr = '';
                expected = [];
                for (p in table[state]) {
                    if (this.terminals_[p] && p > TERROR) {
                        expected.push('\'' + this.terminals_[p] + '\'');
                    }
                }
                if (lexer.showPosition) {
                    errStr = 'Parse error on line ' + (yylineno + 1) + ':\n' + lexer.showPosition() + '\nExpecting ' + expected.join(', ') + ', got \'' + (this.terminals_[symbol] || symbol) + '\'';
                } else {
                    errStr = 'Parse error on line ' + (yylineno + 1) + ': Unexpected ' + (symbol == EOF ? 'end of input' : '\'' + (this.terminals_[symbol] || symbol) + '\'');
                }
                this.parseError(errStr, {
                    text: lexer.match,
                    token: this.terminals_[symbol] || symbol,
                    line: lexer.yylineno,
                    loc: yyloc,
                    expected: expected
                });
            }
        if (action[0] instanceof Array && action.length > 1) {
            throw new Error('Parse Error: multiple actions possible at state: ' + state + ', token: ' + symbol);
        }
        switch (action[0]) {
        case 1:
            stack.push(symbol);
            vstack.push(lexer.yytext);
            lstack.push(lexer.yylloc);
            stack.push(action[1]);
            symbol = null;
            if (!preErrorSymbol) {
                yyleng = lexer.yyleng;
                yytext = lexer.yytext;
                yylineno = lexer.yylineno;
                yyloc = lexer.yylloc;
                if (recovering > 0) {
                    recovering--;
                }
            } else {
                symbol = preErrorSymbol;
                preErrorSymbol = null;
            }
            break;
        case 2:
            len = this.productions_[action[1]][1];
            yyval.$ = vstack[vstack.length - len];
            yyval._$ = {
                first_line: lstack[lstack.length - (len || 1)].first_line,
                last_line: lstack[lstack.length - 1].last_line,
                first_column: lstack[lstack.length - (len || 1)].first_column,
                last_column: lstack[lstack.length - 1].last_column
            };
            if (ranges) {
                yyval._$.range = [
                    lstack[lstack.length - (len || 1)].range[0],
                    lstack[lstack.length - 1].range[1]
                ];
            }
            r = this.performAction.apply(yyval, [
                yytext,
                yyleng,
                yylineno,
                sharedState.yy,
                action[1],
                vstack,
                lstack
            ].concat(args));
            if (typeof r !== 'undefined') {
                return r;
            }
            if (len) {
                stack = stack.slice(0, -1 * len * 2);
                vstack = vstack.slice(0, -1 * len);
                lstack = lstack.slice(0, -1 * len);
            }
            stack.push(this.productions_[action[1]][0]);
            vstack.push(yyval.$);
            lstack.push(yyval._$);
            newState = table[stack[stack.length - 2]][stack[stack.length - 1]];
            stack.push(newState);
            break;
        case 3:
            return true;
        }
    }
    return true;
}};

/* generated by jison-lex 0.3.4 */
var lexer = (function(){
var lexer = ({

EOF:1,

parseError:function parseError(str, hash) {
        if (this.yy.parser) {
            this.yy.parser.parseError(str, hash);
        } else {
            throw new Error(str);
        }
    },

// resets the lexer, sets new input
setInput:function (input, yy) {
        this.yy = yy || this.yy || {};
        this._input = input;
        this._more = this._backtrack = this.done = false;
        this.yylineno = this.yyleng = 0;
        this.yytext = this.matched = this.match = '';
        this.conditionStack = ['INITIAL'];
        this.yylloc = {
            first_line: 1,
            first_column: 0,
            last_line: 1,
            last_column: 0
        };
        if (this.options.ranges) {
            this.yylloc.range = [0,0];
        }
        this.offset = 0;
        return this;
    },

// consumes and returns one char from the input
input:function () {
        var ch = this._input[0];
        this.yytext += ch;
        this.yyleng++;
        this.offset++;
        this.match += ch;
        this.matched += ch;
        var lines = ch.match(/(?:\r\n?|\n).*/g);
        if (lines) {
            this.yylineno++;
            this.yylloc.last_line++;
        } else {
            this.yylloc.last_column++;
        }
        if (this.options.ranges) {
            this.yylloc.range[1]++;
        }

        this._input = this._input.slice(1);
        return ch;
    },

// unshifts one char (or a string) into the input
unput:function (ch) {
        var len = ch.length;
        var lines = ch.split(/(?:\r\n?|\n)/g);

        this._input = ch + this._input;
        this.yytext = this.yytext.substr(0, this.yytext.length - len);
        //this.yyleng -= len;
        this.offset -= len;
        var oldLines = this.match.split(/(?:\r\n?|\n)/g);
        this.match = this.match.substr(0, this.match.length - 1);
        this.matched = this.matched.substr(0, this.matched.length - 1);

        if (lines.length - 1) {
            this.yylineno -= lines.length - 1;
        }
        var r = this.yylloc.range;

        this.yylloc = {
            first_line: this.yylloc.first_line,
            last_line: this.yylineno + 1,
            first_column: this.yylloc.first_column,
            last_column: lines ?
                (lines.length === oldLines.length ? this.yylloc.first_column : 0)
                 + oldLines[oldLines.length - lines.length].length - lines[0].length :
              this.yylloc.first_column - len
        };

        if (this.options.ranges) {
            this.yylloc.range = [r[0], r[0] + this.yyleng - len];
        }
        this.yyleng = this.yytext.length;
        return this;
    },

// When called from action, caches matched text and appends it on next action
more:function () {
        this._more = true;
        return this;
    },

// When called from action, signals the lexer that this rule fails to match the input, so the next matching rule (regex) should be tested instead.
reject:function () {
        if (this.options.backtrack_lexer) {
            this._backtrack = true;
        } else {
            return this.parseError('Lexical error on line ' + (this.yylineno + 1) + '. You can only invoke reject() in the lexer when the lexer is of the backtracking persuasion (options.backtrack_lexer = true).\n' + this.showPosition(), {
                text: "",
                token: null,
                line: this.yylineno
            });

        }
        return this;
    },

// retain first n characters of the match
less:function (n) {
        this.unput(this.match.slice(n));
    },

// displays already matched input, i.e. for error messages
pastInput:function () {
        var past = this.matched.substr(0, this.matched.length - this.match.length);
        return (past.length > 20 ? '...':'') + past.substr(-20).replace(/\n/g, "");
    },

// displays upcoming input, i.e. for error messages
upcomingInput:function () {
        var next = this.match;
        if (next.length < 20) {
            next += this._input.substr(0, 20-next.length);
        }
        return (next.substr(0,20) + (next.length > 20 ? '...' : '')).replace(/\n/g, "");
    },

// displays the character position where the lexing error occurred, i.e. for error messages
showPosition:function () {
        var pre = this.pastInput();
        var c = new Array(pre.length + 1).join("-");
        return pre + this.upcomingInput() + "\n" + c + "^";
    },

// test the lexed token: return FALSE when not a match, otherwise return token
test_match:function (match, indexed_rule) {
        var token,
            lines,
            backup;

        if (this.options.backtrack_lexer) {
            // save context
            backup = {
                yylineno: this.yylineno,
                yylloc: {
                    first_line: this.yylloc.first_line,
                    last_line: this.last_line,
                    first_column: this.yylloc.first_column,
                    last_column: this.yylloc.last_column
                },
                yytext: this.yytext,
                match: this.match,
                matches: this.matches,
                matched: this.matched,
                yyleng: this.yyleng,
                offset: this.offset,
                _more: this._more,
                _input: this._input,
                yy: this.yy,
                conditionStack: this.conditionStack.slice(0),
                done: this.done
            };
            if (this.options.ranges) {
                backup.yylloc.range = this.yylloc.range.slice(0);
            }
        }

        lines = match[0].match(/(?:\r\n?|\n).*/g);
        if (lines) {
            this.yylineno += lines.length;
        }
        this.yylloc = {
            first_line: this.yylloc.last_line,
            last_line: this.yylineno + 1,
            first_column: this.yylloc.last_column,
            last_column: lines ?
                         lines[lines.length - 1].length - lines[lines.length - 1].match(/\r?\n?/)[0].length :
                         this.yylloc.last_column + match[0].length
        };
        this.yytext += match[0];
        this.match += match[0];
        this.matches = match;
        this.yyleng = this.yytext.length;
        if (this.options.ranges) {
            this.yylloc.range = [this.offset, this.offset += this.yyleng];
        }
        this._more = false;
        this._backtrack = false;
        this._input = this._input.slice(match[0].length);
        this.matched += match[0];
        token = this.performAction.call(this, this.yy, this, indexed_rule, this.conditionStack[this.conditionStack.length - 1]);
        if (this.done && this._input) {
            this.done = false;
        }
        if (token) {
            return token;
        } else if (this._backtrack) {
            // recover context
            for (var k in backup) {
                this[k] = backup[k];
            }
            return false; // rule action called reject() implying the next rule should be tested instead.
        }
        return false;
    },

// return next match in input
next:function () {
        if (this.done) {
            return this.EOF;
        }
        if (!this._input) {
            this.done = true;
        }

        var token,
            match,
            tempMatch,
            index;
        if (!this._more) {
            this.yytext = '';
            this.match = '';
        }
        var rules = this._currentRules();
        for (var i = 0; i < rules.length; i++) {
            tempMatch = this._input.match(this.rules[rules[i]]);
            if (tempMatch && (!match || tempMatch[0].length > match[0].length)) {
                match = tempMatch;
                index = i;
                if (this.options.backtrack_lexer) {
                    token = this.test_match(tempMatch, rules[i]);
                    if (token !== false) {
                        return token;
                    } else if (this._backtrack) {
                        match = false;
                        continue; // rule action called reject() implying a rule MISmatch.
                    } else {
                        // else: this is a lexer rule which consumes input without producing a token (e.g. whitespace)
                        return false;
                    }
                } else if (!this.options.flex) {
                    break;
                }
            }
        }
        if (match) {
            token = this.test_match(match, rules[index]);
            if (token !== false) {
                return token;
            }
            // else: this is a lexer rule which consumes input without producing a token (e.g. whitespace)
            return false;
        }
        if (this._input === "") {
            return this.EOF;
        } else {
            return this.parseError('Lexical error on line ' + (this.yylineno + 1) + '. Unrecognized text.\n' + this.showPosition(), {
                text: "",
                token: null,
                line: this.yylineno
            });
        }
    },

// return next match that has a token
lex:function lex() {
        var r = this.next();
        if (r) {
            return r;
        } else {
            return this.lex();
        }
    },

// activates a new lexer condition state (pushes the new lexer condition state onto the condition stack)
begin:function begin(condition) {
        this.conditionStack.push(condition);
    },

// pop the previously active lexer condition state off the condition stack
popState:function popState() {
        var n = this.conditionStack.length - 1;
        if (n > 0) {
            return this.conditionStack.pop();
        } else {
            return this.conditionStack[0];
        }
    },

// produce the lexer rule set which is active for the currently active lexer condition state
_currentRules:function _currentRules() {
        if (this.conditionStack.length && this.conditionStack[this.conditionStack.length - 1]) {
            return this.conditions[this.conditionStack[this.conditionStack.length - 1]].rules;
        } else {
            return this.conditions["INITIAL"].rules;
        }
    },

// return the currently active lexer condition state; when an index argument is provided it produces the N-th previous condition state, if available
topState:function topState(n) {
        n = this.conditionStack.length - 1 - Math.abs(n || 0);
        if (n >= 0) {
            return this.conditionStack[n];
        } else {
            return "INITIAL";
        }
    },

// alias for begin(condition)
pushState:function pushState(condition) {
        this.begin(condition);
    },

// return the number of states currently on the stack
stateStackSize:function stateStackSize() {
        return this.conditionStack.length;
    },
options: {"flex":true},
performAction: function anonymous(yy,yy_,$avoiding_name_collisions,YY_START) {
var YYSTATE=YY_START;
switch($avoiding_name_collisions) {
case 0: this.begin('cond_include'); 
break;
case 1: yy.filepath = yy_.yytext; 
break;
case 2: yy.filename = yy_.yytext; 
break;
case 3:  this.popState(); 
break;
case 4: this.begin('cond_use');
break;
case 5: yy.filename = yy_.yytext; 
break;
case 6: this.popState(); 
break;
case 7:return 9
break;
case 8:return 21
break;
case 9:return 26
break;
case 10:return 28
break;
case 11:return 35
break;
case 12:return 36
break;
case 13:return 37
break;
case 14: stringcontents += '    ';  
break;
case 15: stringcontents += '\n';  
break;
case 16: stringcontents += '\"';  
break;
case 17: stringcontents += '\r';  
break;
case 18: stringcontents += '\\';  
break;
case 19: stringcontents += '\0';  
break;
case 20: stringcontents += '\a';  
break;
case 21: stringcontents += '\b';  
break;
case 22: stringcontents += '\t';  
break;
case 23: stringcontents += '\n';  
break;
case 24: stringcontents += '\v';  
break;
case 25: stringcontents += '\f';  
break;
case 26: stringcontents += '\e';  
break;
case 27: /*"*/
                                stringcontents += yy_.yytext;
                            
break;
case 28:
                                this.popState();
                                yy_.yytext = stringcontents;
                                return 39;
                            
break;
case 29: /*"*/
                                this.begin('cond_string');
                                stringcontents = "";
                            
break;
case 30:/* Ignore */
break;
case 31:/* Ignore */
break;
case 32:/* Ignore */
break;
case 33:/* Ignore Note: multi-line comments are removed via a preparse regex. */
break;
case 34:return 40
break;
case 35:return 40
break;
case 36:return 40
break;
case 37:return 10
break;
case 38:return 49
break;
case 39:return 52
break;
case 40:return 50
break;
case 41:return 51
break;
case 42:return 54
break;
case 43:return 55
break;
case 44:return yy_.yytext;
break;
case 45:console.log(yy_.yytext);
break;
}
},
rules: [/^(?:include[ \t\r\n>]*<)/,/^(?:[^\t\r\n>]*\/)/,/^(?:[^\t\r\n>\/]+)/,/^(?:>)/,/^(?:use[ \t\r\n>]*<)/,/^(?:[^\t\r\n>]+)/,/^(?:>)/,/^(?:module)/,/^(?:function)/,/^(?:if)/,/^(?:else)/,/^(?:true)/,/^(?:false)/,/^(?:undef)/,/^(?:\\t)/,/^(?:\\n)/,/^(?:\\")/,/^(?:\\r)/,/^(?:\\\\)/,/^(?:\\0)/,/^(?:\\a)/,/^(?:\\b)/,/^(?:\\t)/,/^(?:\\n)/,/^(?:\\v)/,/^(?:\\f)/,/^(?:\\e)/,/^(?:[^\\\n\"]+)/,/^(?:")/,/^(?:[\"])/,/^(?:[\n])/,/^(?:[\r\t ])/,/^(?:\/\/[^\n]*\n?)/,/^(?:\/\*.+\*\/)/,/^(?:([0-9])*\.([0-9])+([Ee][+-]?([0-9])+)?)/,/^(?:([0-9])+\.([0-9])*([Ee][+-]?([0-9])+)?)/,/^(?:([0-9])+([Ee][+-]?([0-9])+)?)/,/^(?:\$?[a-zA-Z0-9_]+)/,/^(?:<=)/,/^(?:>=)/,/^(?:==)/,/^(?:!=)/,/^(?:&&)/,/^(?:\|\|)/,/^(?:.)/,/^(?:.)/],
conditions: {"cond_include":{"rules":[0,1,2,3,4,7,8,9,10,11,12,13,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45],"inclusive":true},"cond_use":{"rules":[0,4,5,6,7,8,9,10,11,12,13,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45],"inclusive":true},"cond_comment":{"rules":[0,4,7,8,9,10,11,12,13,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45],"inclusive":true},"cond_string":{"rules":[0,4,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45],"inclusive":true},"cond_import":{"rules":[0,4,7,8,9,10,11,12,13,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45],"inclusive":true},"INITIAL":{"rules":[0,4,7,8,9,10,11,12,13,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45],"inclusive":true}}
});
return lexer;
})();
parser.lexer = lexer;
function Parser () {
  this.yy = {};
}
Parser.prototype = parser;parser.Parser = Parser;
return new Parser;
})();


if (typeof require !== 'undefined' && typeof exports !== 'undefined') {
exports.parser = parser;
exports.Parser = parser.Parser;
exports.parse = function () { return parser.parse.apply(parser, arguments); };
exports.main = function commonjsMain(args) {
    if (!args[1]) {
        console.log('Usage: '+args[0]+' FILE');
        process.exit(1);
    }
    var source = require('fs').readFileSync(require('path').normalize(args[1]), "utf8");
    return exports.parser.parse(source);
};
if (typeof module !== 'undefined' && require.main === module) {
  exports.main(process.argv.slice(1));
}
}
}).call(this,require('_process'))
},{"./ArgContainer":11,"./ArgsContainer":12,"./Expression":17,"./IfElseModuleInstantiation":20,"./ModuleInstantiation":24,"./openscad-parser-ext":31,"_process":4,"fs":1,"path":3}],34:[function(require,module,exports){
var parser = require('./parserCJS')
var Globals = require('./Globals')

module.exports = {
  parse: function (text) {
    if (parser.yy === undefined) {
      parser.yy = {}
    }

    var openSCADText = Globals.preParse(text)
    var openJSCADResult = parser.parse(openSCADText)
    return openJSCADResult.lines.join('\n')
  }
}

},{"./Globals":19,"./parserCJS":33}]},{},[34])(34)
});