I've been clear to make things work just fine with `\` (parsed with LALRPOP), `abs!`, and `app!`. I've only been pasting in a few in READMEs and standard const

I've been clear to make things work just fine with `\` (parsed with LALRPOP), `abs!`, and `app!`. I've only been pasting in a few in READMEs and standard constants for brevity.