Path: utzoo!attcan!uunet!mcsun!unido!ecrc!ecrc!thom
From: thom@ecrc.de (Thom Fruehwirth)
Newsgroups: comp.lang.prolog
Subject: Re:  general data structures are impossible
Message-ID: <1991Feb15.101435.16112@ecrc.de>
Date: 15 Feb 91 10:14:35 GMT
References: <1991Feb12.013413.24312@cs.ubc.ca> <4765@goanna.cs.rmit.oz.au> <1991Feb13.235655.6202@cs.ubc.ca> <17853@cs.utexas.edu> <1948@n-kulcs.cs.kuleuven.ac.be> <17899@cs.utexas.edu>
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Reply-To: thom@ecrc.de (Thom Fruehwirth)
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One of the main achievements of Prolog is that pointer manipulation is
replaced by the concept of unification and the logical variable.

I don't see why infinite data structures are 'impenetrable mazes' and
'tangled webs' (as pop@cs.umass.edu put it). I also can't follow her/his
comments that 'variables would be unbound as soon as each recursive subgoal
suceeded' and why (s)he suggests using the assert-predicate.

thom