- stack-checker.state vocabulary split up into stack-checker.{state,values,recursive-state}
- code that modifies and searches recursive state factored out into stack-checker.recursive-state
- recursive state is now a set of three binary hash trees instead of an alist, and no longer contains unnecessary data
- binary hash trees are in stack-checker.recursive-state.tree: unbalanced, persistent
- ~8 second speedup on bootstrap, ~20 second speedup in "peg.javascript" require
array is now part of the tuple layout object itself, and class hashcodes
are stored alongside class words there. This removes 2 indirections when
reading a superclass, and 3 when reading a superclass hashcode.