This is a game changer. I've used it over the last few 3 or 4 months, and it is really stable and usable. I am betting an entire (although academic) project on it: http://proofpeer.net (note that Clojure is mentioned there as a language of choice, but I switched to Scala since then as Scala provides a similar level of conciseness with all the goodies of a powerful static type system with support for both Java and Javascript).
Wow! I started working on a very similar idea half a year ago -- with machine learning and everything (my domain was proofgraph.org). I had to suspend it since it is larger than a one mans freetime project. I am very glad that someone started with a similar idea!
Will it be open source? I would be happy to contribute (I work full-time with Scala).
I like static typing, but do you ever get the feeling that we've collectively gone off the deep end with the whole backwards compatibility hacks that compile-to-javascript languages represent? Think about it...we have implementations of static languages on top of a dynamic runtime that translates it back to a static runtime. We have non-GC languages that have developed ways to compile to a GC language and avoid GC. It is absolutely amazing, and completely silly at the same time.
Indeed. It's almost as if the ECMA should just freeze all JavaScript development, and replace it with a standard, low level, high performance compiler target that all browsers can implement instead, and then just let the industry/community write competing compiled languages for it. That's essentially where browsers are heading anyway with asm.js and NACL.
For everyone who still loves JS and prefers it over Coffee/Type/Clojure/etc-scripts, just make a JS compiler and keep all its quirks and wtfs.
I also keep thinking of it as a game changer. Why ever bother with prototypes again when you have case classes, or callbacks when you have function shorthands. I fully expect Scala.js code to be more concise and maintainable than Javascript code, and will probably perform better too thanks to the Closure compiler.
