That's very cool. Are you aware of similar tools written in languages other than JavaScript?

Hi Andrea -- https://github.com/darius/parson is in Python. It's probably not very similar because I haven't got around to studying Ohm, but it shares the basic goal of not writing semantic actions inline in some particular language. (I wrote it in my first Recurse Center stint back in 2012.)

Hi Darius (it's a small world).

That looks really good, I'll have a look at it!