diff --git a/mindplot/src/main/javascript/commands/ChangeLinkToTopicCommand.js b/mindplot/src/main/javascript/commands/ChangeLinkToTopicCommand.js
index ef259057..3578b12d 100644
--- a/mindplot/src/main/javascript/commands/ChangeLinkToTopicCommand.js
+++ b/mindplot/src/main/javascript/commands/ChangeLinkToTopicCommand.js
@@ -19,7 +19,7 @@
 mindplot.commands.ChangeLinkToTopicCommand = new Class({
     Extends:mindplot.Command,
     initialize: function(topicId, url) {
-        $assert(topicId, 'topicId can not be null');
+        $assert($defined(topicId), 'topicId can not be null');
         this._topicsIds = topicId;
         this._url = url;
         this._id = mindplot.Command._nextUUID();
diff --git a/mindplot/src/main/javascript/commands/ChangeNoteToTopicCommand.js b/mindplot/src/main/javascript/commands/ChangeNoteToTopicCommand.js
index 6c3ad86c..117d97c7 100644
--- a/mindplot/src/main/javascript/commands/ChangeNoteToTopicCommand.js
+++ b/mindplot/src/main/javascript/commands/ChangeNoteToTopicCommand.js
@@ -19,14 +19,14 @@
 mindplot.commands.ChangeNoteToTopicCommand = new Class({
     Extends:mindplot.Command,
     initialize: function(topicId, text) {
-        $assert(topicId, 'topicId can not be null');
+        $assert($defined(topicId), 'topicId can not be null');
         this._topicsIds = topicId;
         this._text = text;
         this._oldtext = null;
         this._id = mindplot.Command._nextUUID();
     },
 
-     execute: function(commandContext) {
+    execute: function(commandContext) {
         var topic = commandContext.findTopics(this._topicsIds)[0];
         if (topic.hasNote()) {
             var model = topic.getModel();
diff --git a/mindplot/src/main/javascript/commands/GenericFunctionCommand.js b/mindplot/src/main/javascript/commands/GenericFunctionCommand.js
index b2552103..00d9f576 100644
--- a/mindplot/src/main/javascript/commands/GenericFunctionCommand.js
+++ b/mindplot/src/main/javascript/commands/GenericFunctionCommand.js
@@ -20,7 +20,7 @@ mindplot.commands.GenericFunctionCommand = new Class({
     Extends:mindplot.Command,
     initialize: function(commandFunc, topicsIds,value) {
         $assert(commandFunc, "commandFunc must be defined");
-        $assert(topicsIds, "topicsIds must be defined");
+        $assert($defined(topicsIds), "topicsIds must be defined");
 
         this._value = value;
         this._topicsIds = topicsIds;