This should make it a bit more possible to crawl through a whole Arc program and source-to-source translate it into JavaScript at runtime. I don't think it'll be an airtight transformation by any means, but that's a use case that's been in the back of my mind when thinking about closure reflection in Penknife, ever since evanrmurphy's attempts to translate Arc.
Mutating functions has been on my mind too, but only for a JIT, and I wouldn't know where to start. If PyArc did its own JIT, that'd be pretty fantastic.
