diff --git a/core/generator.js b/core/generator.js
index cba266f27..81feb8f78 100644
--- a/core/generator.js
+++ b/core/generator.js
@@ -366,7 +366,7 @@ Blockly.Generator.prototype.provideFunction_ = function(desiredName, code) {
     var oldCodeText;
     while (oldCodeText != codeText) {
       oldCodeText = codeText;
-      codeText = codeText.replace(/^((  )*)  /gm, '$1\0');
+      codeText = codeText.replace(/^(( {2})*) {2}/gm, '$1\0');
     }
     codeText = codeText.replace(/\0/g, this.INDENT);
     this.definitions_[desiredName] = codeText;