From p.singleton@keele.ac.uk  Tue Apr 18 14:46:03 2000
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Date: Tue, 18 Apr 2000 13:45:26 +0100
From: Paul Singleton <p.singleton@keele.ac.uk>
Organization: SmartArts Computing Consultancy
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To: SWI Prolog <prolog@swi.psy.uva.nl>
Subject: term comparison in foreign code
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How, from within foreign code, can we determine whether two variables
are shared?

Is PL_compare() the only way?

Or is there some identifier, unique to each distinct variable, which
can be used e.g. to maintain a map of variables-seen-so-far when
traversing a term?

Paul Singleton

