Thanks; I just checked it out and while it has some nice features, it doesn't do all that much to compact my already-dense JS. Additionally, the added complexity it introduces to the development process negates some of its charm, as does the extra cognitive load of playing human backtracking parser whenever I have to think about what function applications require parens and which don't. (This is all IMO, so while I think I've accurately portrayed CoffeeScript, YMMV, so people should check it for themselves.)

> function applications require parens and which don't.

Yes. An understanding of JS is definitely necessary when developing with CoffeeScript. The ambiguity that the parser allows sometimes leads to code generation that isn't at all what you intended. I sometimes find myself going into the JS output to make sure the compiler did what I intended.

Annoying, but at least for me, the benefits of cleanliness and things like list comprehensions and Python-esque list semantics makes it worthwhile.