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From: duchier@cs.yale.edu (Denys Duchier)
Newsgroups: comp.lang.prolog
Subject: Re: Lists (was Arrays) in Prolog
Message-ID: <DUCHIER.90Oct5120348@albania.cs.yale.edu>
Date: 5 Oct 90 16:03:48 GMT
References: <1238@ecrc.de> <1990Sep19.075314.14372@irisa.fr> <1403@ecrc.de>
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	<DUCHIER.90Oct4112110@albania.cs.yale.edu> <6015@hplabsz.HPL.HP.COM>
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In-reply-to: kirshenb@hplabsz.HPL.HP.COM's message of 5 Oct 90 00:09:19 GMT

In article <6015@hplabsz.HPL.HP.COM> kirshenb@hplabsz.HPL.HP.COM (Evan Kirshenbaum) writes:
 >   >        [..X foo] to be unified with [foo ..Y]
 >   >
 >   >The set of unifiers for this example is:
 >   >
 >   >        { X = Y = [] }
 >   >        { X = Y = [foo] }
 >   >        { X = Y = [foo foo] }
 >   >        { X = Y = [foo foo foo] }
 >   >        ...
 >
 >   Actually, [..X, foo] unified with [foo, ..Y] would yield
 >	   X = Y = []
 >	   and
 >	   X = [foo, ..A], Y = [..A, foo]

This can't be right! ..A must be constrained to be a sequence of
foo's only.

--Denys