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ASSOC and ASSQ on lists with atomic entries


1) as for maclisp, it appears to be a bug  in the manual that this
   isn't documented - the manual seems to imply that "association lists"
   must contain only dotted pairs.  The "feature" of maclisp's ASSQ 
   under which it really takes car of each item in the association
   list must be considered a speed kludge in the same cattegory as that
   of converting ATOM check for end of list in the various MAPs into
   a NULL check in compiled code;  one  could construct pathological
   cases which exploited/demonstrated this difference, but in fact in
   the 5+ years that it has been installed, there has never been a
   naturally-occurring complaing agains ASSQ/ASSOC.  (on the other hand,
   there have been a few complaints that compiled MAPs do not do the
   same endtest check as the interpreted version, i.e. that NULL has
   been substituted for ATOM).
2) the utility of being able to delete entries from an "association list"
   by means of RPLACAing them to (), rather than having to re-invent
   and/or open-code the mechanisms of DELETE, is supremely useful;  
   likely we should ensure that all of MACLISP/LISPM/NIL permit it.
3) some of us will receive multiple copies of this note, due to the
   mail-forwarding process - should we perhaps define a new mailing
   list which reaches BUG-LISP, BUG-LISPM, and NIL mailing lists?