Trees that grow introduces a lot of boilerplate but is bound to be essentially necessary
when I add in the type checker and all sorts of builtin data types.
(I know this because I already *implemented* those things;
it's mostly a matter of trying to merge it all into this codebase).
Accomplishing this also involved restructuring the project
and rewriting a few algorithms in the process,
but those changes are fundamentally intwined with this one.
James T. Martin