(fast-alist-summary)
prints some basic statistics about any current fast
alists.
Major Section: HONS-AND-MEMOIZATION
Logically, fast-alist-summary
just returns nil; we leave it enabled and
would think it odd to ever prove a theorem about it.
Under the hood, this function gathers and prints some basic statistics about
the current fast alists. It may be useful for identifying fast alists that
should have been freed with fast-alist-free