For lots of reasons, this is very impressive. As I am still learning Perl 5, I've had a hard time internalizing Perl 6 regexen. Overall, you've shown the nay sayers and doubters what can be done with the new syntax (and given me something to analyze while I wait for Exegesis 5 :-).

A nit, though. I don't know diddly 'bout JavaScript, but are backslashed backslashes allowed in strings? If so, this grammar doesn't allow for this.

Light a man a fire, he's warm for a day. Catch a man on fire, and he's warm for the rest of his life. - Terry Pratchet