Looks fantastic.
With the traction Coffeescript is getting I wouldn't be surprised to see it eventually execute directly inside v8 or similar, bypassing the javascript compilation altogether.
With the traction Coffeescript is getting I wouldn't be surprised to see it eventually execute directly inside v8 or similar, bypassing the javascript compilation altogether.
Although I doubt that any of the browsers will ever support it directly, porting coffeescript to run directly on top of Jaegermonkey or v8 wouldn't be too hard, since there is a direct translation from coffeescript to javascript. You would only need a new front end--if you emit Spidermonkey/Hydrogen bytecode, the relevant engine can JIT it.
On a slightly related note, a friend of mine is working on this: https://wiki.mozilla.org/DevTools/Features/SourceMap
Which, while not compiling directly, will allow you to map the generated JS directly back to the coffeescript source.
Hydrogen is not a bytecode, it is highlevel intermediate representation for optimizing compiler generated from AST. There is currently: 1) no frontend in V8 that accepts hydrogen in some serialized form; 2) no way to generate non-optimized (non-specialized) code from hydrogen which is quite crucial to make adaptive optimization pipeline running.
Also it'd be the only way for me to be sure my CS is compiled by the proper compiler version.