Path: utzoo!utgpu!watmath!att!dptg!rutgers!cs.utexas.edu!uunet!mcsun!ukc!edcastle!lfcs!db
From: db@lfcs.ed.ac.uk (Dave Berry)
Newsgroups: comp.lang.misc
Subject: Re: What I'd really like to see in an if-statement...
Message-ID: <282@castle.ed.ac.uk>
Date: 30 Aug 89 18:28:45 GMT
References: <13359@megaron.arizona.edu>
Sender: root@castle.ed.ac.uk
Reply-To: db@lfcs.ed.ac.uk (Dave Berry)
Organization: Laboratory for the Foundations of Computer Science, Edinburgh U
Lines: 19

In article <13359@megaron.arizona.edu> gudeman@arizona.edu (David Gudeman) writes:
>In article  <8620@batcomputer.tn.cornell.edu> lacey@batcomputer.tn.cornell.edu (John Lacey) writes:
>>In talking about _Real Conditionals_ :), 
>>So far, Lisp, Icon, and BCPL have all tried and failed to meet the challenge
>
>Urr.  I thought both Lisp and Icon succeeded.  They both evaluate each
>argument exactly once and produce a conditional result that is true
>exactly when the corresponding value in math is true.

I agree about Icon, but are you sure about Lisp?  I thought that
(< a b) returned either t or nil.  If so, although it can handle
cases like (< a b c d), it can't handle (<= (< a b) c).

Any functional language can write the equivalent of (< a b c d).

Dave Berry, Laboratory for Foundations      db%lfcs.ed.ac.uk@nsfnet-relay.ac.uk
    of Computer Science, Edinburgh Uni.	    <Atlantic Ocean>!mcvax!ukc!lfcs!db

   "Another hope, another dream, another truth, installed by the machine."