Re: Occurs check

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Article #2210

#2210

From: Saumya K. Debray
Date: Thu, 17 Dec 1992 18:50

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Fernando Pereira writes:
> Nonetheless, the efficiency reasons that led to Prolog's
> unification not having the check are pretty compelling, so I do not advocate
> adding it to Prolog in all cases. 

While I believe this statement, it would be interesting to actually see some
numbers (preferably for programs other than nrev) showing how much more
expensive unification becomes with the occurs check.  Do the implementors
of Sepia, NU-Prolog, and other systems that provide both kinds of
unification have any numbers they'd care to post?
-- 
Saumya Debray
CIS Dept, University of Oregon, Eugene, OR
debray@cs.uoregon.edu

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From: debray@majestix.cs.uoregon.edu (Saumya K. Debray)
Newsgroups: comp.lang.prolog
Subject: Re: Occurs check
Message-ID: <1992Dec17.185017.17766@cs.uoregon.edu>
Date: 17 Dec 92 18:50:17 GMT
References: <1992Dec13.173016.8849@nntp.hut.fi> <1992Dec17.111142.24450@dcs.qmw.ac.uk> <24435@alice.att.com>
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