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From: jeff@aiai.uucp (Jeff Dalton)
Newsgroups: comp.lang.lisp
Subject: Re: Total ordering for Lisp objects ?
Message-ID: <881@skye.ed.ac.uk>
Date: 13 Sep 89 15:39:35 GMT
References: <5896@lifia.imag.fr> <865@skye.ed.ac.uk> <2084@munnari.oz.au> <4932@ubc-cs.UUCP> <29362@news.Think.COM>
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Reply-To: jeff@aiai.uucp (Jeff Dalton)
Organization: AIAI, University of Edinburgh, Scotland
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In article <29362@news.Think.COM> barmar@think.COM (Barry Margolin) writes:
>Prolog has no destructive assignment, so it doesn't suffer
>such problems.

But Prolog has something very like destructive assignment, namely
variable instantiation.  For example, you might have a structure
that contains an uninstantiated variable, and then its position
in the total ordering will change after you instantiate the variable.

-- Jeff