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Re: REDUCE args

    Date: 24 Jul 1986 13:39-EDT

	Date: Thu, 24 Jul 1986  13:11 EDT
	To:   common-lisp@SU-AI.ARPA
	Subject: REDUCE args
	In-Reply-To: Msg of 24 Jul 1986  00:23-EDT from NGALL at G.BBN.COM
	Message-ID: <ALR.12225273192.BABYL@MIT-OZ>
	Does anybody else wish that REDUCE took a KEY argument, similarly to MEMBER.
	(reduce #'+ list-of-objects :KEY #'object-quantity)
	would apply the function OBJECT-QUANTITY to each element of the
	list-of-objects before reducing it with +.
    YES!  I ran into the same need a while back.

Ditto.  I think GLS made some comment about this usage of :KEY being
different than most.  Maybe that was in a different discussion.  There
are possibly other related operations that should take KEY.  One could
also add :TEST to avoid calling the operator on objects you don't want
to.  Maybe this was Steele's point: Does the key apply before or after
the test?  I think the intuitive usage is backwards from the other