So far, we've seen several arguments for and against CoffeeScript:

https://github.com/raganwald/homoiconic/blob/master/2011/12/jargon.md#readme

http://www.codethinked.com/a-case-for-using-coffeescript

http://userinexperience.com/?p=732

etc.

From my experience and all the arguments presented by both sides, CS appears to be an excellent tool when put in the right hands and used in a well set up development environment that has been tailored for coding in CoffeeScript.

The choice to use CoffeeScript or not appears to be as much a religious war as Emacs vs. Vim. Most arguments boil down to taste, and in some cases the social contract regarding tools that you've established with your team.

The question I have is if CoffeeScript in open-source Javascript libraries is a net positive or net negative for Javascript. I can see arguments for both sides, but if the stakes aren't discussed I can see a potential tragedy of the commons where there are increasingly two versions of every javascript library, the one written in Javascript that receives few contributions from those who spend most of their time in CoffeeScript and those written in CoffeeScript that receive few contributions from those who don't use CoffeeScript and haven't tooled their environment to work effectively with it.

Despite the contentiousness of this issue, I'm curious to hear what others think.

Please leave your personal preferences at home (your dev env) and try to only discuss the pros and cons of CoffeeScript being used in open-source libraries and the impact is has on our community.

Social issues, community issues and language evolutions are fair game. Discussions of syntax preference should be avoided.