That's interesting. I've "used" Parse::RecDescent but never stressed it. I got a basic intro to Parrot's compiler tools last week. I'm curious now how that would fare. You get to write a grammar in Perl 6, annotate your productions with associativity information and other stuff. This goes right to an AST which you can register events against. From there, you produce an opcode syntax tree and from there you get byte code.

This is a tool aimed at this kind of task, y'know? It ought to be decent.