By the way, regarding the title of this post... I've already been working on arc2js[1], and evanmurphy also has LavaScript[2]. So yes, we are working on a "comparable" thing for Arc. I'm in the process right now of rewriting large chunks of my compiler, and hopefully I'll be able to make a release within the next couple weeks.
I've been adding in some stuff like static analysis, so it can know which variables are free, and use that information to do things like shorten variable names. I'll note that the version of arc2js that's on git is far outdated compared to the version on my harddrive.
