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Hash tables => Hashing functions



No, because it is very hard/expensive to provide a function that hashes
on EQ (and EQL) in a Lisp with a copying GC.  That's why we provide hash
tables: the system can deal with this but the user can't.  For example,
Lisp Machine hash tables all include a little variable that gets compared
against a global how-many-flips-have-happened counter, and if there has
been a flip since last time, the hash table has to be completely rehashed.
The user should not see this counter, especially not as part of the C.L.
definition.