28 lines
1.2 KiB
Markdown
28 lines
1.2 KiB
Markdown
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## Welcome to the Babel Codebase
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Babel is broken down into three parts:
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- Parsing
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- [Transformation](babel/transformation/)
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- [Generation](babel/generation/)
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**Parsing** is the process of turning a piece of code into an [ESTree spec](https://github.com/estree/estree) compatible AST (Abstract
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Syntax Tree) which is a tree-like object of nodes that _describes_ the code.
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This makes it easier to transform the code over direct string manpulation.
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**Transformation** is the process of taking an AST and manipulating it into
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a new one. For example, Babel might take an ES2015 ArrowFunction and transform
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it into a normal Function which will work in ES5 environments.
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**Generation** is the process of turning an AST back into code. After Babel is
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done transforming the AST, the generation takes over to return normal code.
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---
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Babel's parsing step is done by [Acorn](https://github.com/marijnh/acorn). However, because Babel is implementing
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future standards it maintains a [fork of Acorn](acorn/) in order to do it's job. You can
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see that fork in the "acorn" folder.
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The transformation and generation steps are both handled inside of the Babel
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codebase itself, which is in the "babel" folder here.
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