Somewhat silly question... why not write BSC in JS? I mean, this seems like something that would be a natural fit in a NodeJS environment, and tying into NPM similar to CoffeeScript, Less etc.

I don't mean to come across as an ass, just curious. Though, I do think what you are doing could be a natural extension to CoffeeScript itself.

Also, I would suggest having an htmlEncode(variable) by default, I know that htmlEncode isn't a built-in JS method, but you should want to escape html entities.