I'm flattered. Jsong definitely wouldn't be possible without QUANTUM.
I learned the trick that you mentioned from WebKit source: https://github.com/WebKit/webkit/blob/b387856b9e42476169271f...
It's slightly different there though. I don't think that boolean definition tests (as in `definied`) should be mixed with actual definition value: what if we want to check if `USE_STUFF` is defined, and zero is among possible definition values?