[no subject]

[HIC at MIT-MC (Howard I. Cannon)]

    Date: 18 DEC 1978 2056-EST
    From: BAK at MIT-MC (William A. Kornfeld)

    In general, when you evaluate (memq <atom> <atom>) you get nil.  However
    evaluating (memq 4 2) seems to cause an infinite loop!
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Right!!  This is the canonical "Use NIL check, not atom check for end of lists".
What happens is that normally it ends up doing CDR's to randomness and
since 0 is so common eventually gets NIL.  BUT, probably AC 2 contains a value
that MEMQ sets up, and so it CDR's back to 2, which might point to itself, etc...

Basically, don't pass it atoms!

--howard