[joesb]

You can write CoffeeScript that uses jQuery, so that it compiles down to Javascript that uses jQuery.

You can also use Javascript and jQuery directly.

Or you can write CoffeeScript without using jQuery at all.

[cygwin98]

My concern is that those combinations can significantly reduce Rails apps' maintainability. I wonder if jQuery is that good, can it be rewritten in CoffeeScript? Such that we can settle down at CoffeeScript, which looks like a better language anyway, and get rid of the Javascript fragmentation issue all at once.

[JoelMcCracken]

You really can't write coffeescript without knowing javascript. Really, the /only/ documentation for the language is showing what the compiled javascript looks like, plus maybe handling inheritance a bit better.