environment built through functions, now onto statements
type/scope infra
type stmt mostly there. errors maybe?
type statement working with scope checking/env double decl in note.dj
beginnings of type_expr
tc through track CR
removes arrow binop
tc through modifiers ; now WITH PRIMITIVE NONDET
typecheck functions\!\!\!\! booyah
TYPECHECKING IS ALIVE
TYPECHECKING IS DONE and the examples all work; this corrects the tests. and incr