Re : ERROR - Parse e rror. Internet Explorer has a non-standard intepretation of trailing commas

example:

structure:
      proeject           
            file1.js     
            file2.js

file2.js content:
            steal('./file1.js', function(){
                  return "The world is beautiful ";
            });


and while building console shows error, that "file2.js"  has trailing comma error, and point to row "return "the world is beautiful"', while
the real issue is in "file1.js".

I suppose it is the closure issue. But it is not  easy to find out the real code part to fix when the  file has many dependencies, ant that files have they own dependencies too.