included in the compiled files. (also, misc minor cleanups
notably a new exercise in tut.scrbl)
closes PR 12547 --- there are still a few uses left, but they do not
seem to be coming from Redex proper:
- /Users/robby/git/plt/collects/racket/private/map.rkt still appears
in a bunch of places (there is a separate PR for that I believe),
and
- /Users/robby/git/plt/collects/redex/../private/reduction-semantics.rkt
appears in tl-test.rkt, but I do not see how it
is coming in via Redex code, so hopefully one of the other
PRs that Eli submitted is the real cause. If not, I'll revisit later
Instead of using a hash-table, use the equal-hash-code directly;
this lets me evict entries only when they clobber each other,
and generally keep good cache utilization.
Also, cut the cache size by a factor of 5 while still having a
slight performance improvement on the r6rs test suite benchmark.
On that same benchmark, there are 1714812 misses in the cache, but
only 3485 times is an entry in the cache clobbered
