First if, what is CoffeeScript?

Web definitions

• CoffeeScript is a programming language that compiles statement-by-statement to JavaScript. The language adds syntactic sugar inspired by Ruby and Python to enhance JavaScript's brevity and readability, as well as adding more sophisticated features like array comprehension and pattern matching.

The issue with CoffeeScript is that it eliminates any progressive adoption. It is a purist approach, kind of like the Amish, if you're not borne Amish, tough luck. So for folks with thousands of lines of JavaScript code will have a tough time to convert it to CoffeeScript. You can use the js2coffee API to convert the JavaScript file to CoffeeScript but in my experience that had trouble converting the files. It would convert the file to CoffeeScript without any complaints, but then when trying to generate the CoffeeScript file got errors with guess what: INDENTATION!

Tried to convince the CoffeeScript community on github but got lots of push-back to progressive adoption with comments like "stupid", "crap", "child's comportment", "it's like Ruby, Python", "legacy code" etc. As a matter of interest one of the first comments were that the code needs to be re-designed before converted to CoffeeScript. Well I rest my case then :-)

So far the community on github has been very reluctant to even consider introducing some way to define code-blocks, obviously curly braces is not an option as they use it for json object definitions. They also have no consideration for a progressive adoption where some, if not all, JavaScript syntax will be allowed which means all of us in the real world that have thousands of lines of JavaScript will have a real issue converting it over. Worst, I for one lack the confidence that tools like js2coffee will provide the correct indentation that will determine the flow of control in your code!!! Actually it is hard for me to find enough justification for using spaces or tabs to control the flow of code. It is no wonder that C#, C, C++, Java, all enterprise-scale frameworks still use curly braces. Have never seen an enterprise app built with Ruby or PhP.

Let me know what your concerns are with CoffeeScript and how you dealt with large scale JavaScript conversions to CoffeeScript.