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From: barmar@think.com (Barry Margolin)
Newsgroups: comp.lang.scheme
Subject: Why memq vs memv vs member, etc.?
Message-ID: <1991May10.230057.15591@Think.COM>
Date: 10 May 91 23:00:57 GMT
Sender: news@Think.COM
Organization: Thinking Machines Corporation, Cambridge MA, USA
Lines: 14
Originator: barmar@godot.think.com

Given Scheme's orientation in favor of the use of procedural arguments, I'm
curious about why it uses the old MacLisp style of list searching
procedures, where the equivalence predicate is implicit in the choice of
the procedure, rather than an explicit procedure argument to a single
searching procedure.  This seems to be an area where Common Lisp does what
I'd expect Scheme to do; CL has a single MEMBER function with a :TEST
option, while Scheme has MEMQ, MEMV, and MEMBER.  Why not (member <obj>
<list> eq?) instead of (memq <obj> <list>)?  The same goes for all the
other functions that come in three varieties like this.
-- 
Barry Margolin, Thinking Machines Corp.

barmar@think.com
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