Clean up pseudocode to match planned syntax for the type- and memory-safe
level-2 Mu language.
http://akkartik.name/post/mu-2019-2 is already out of date.
This undoes 5672 in favor of a new plan:
Layers 000 - 099 are for running without syntax sugar. We use them for
building syntax-sugar passes.
Layers 100 and up are for running with all syntax sugar.
The layers are arranged in approximate order so more phases rely on earlier
layers than later ones.
I plan to not use intermediate syntax sugar (just sigils without calls,
or sigils and calls without braces) anywhere except in the specific passes
implementing them.
Further flesh out next-word variant for calls.subx. All the code is
sketched out, and baseline tests pass. No tests yet for new
functionality compared to sigils.subx.
Kartik Agaram