Newsgroups: comp.lang.prolog
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From: ia2@ci.ua.pt (login IA2)
Subject: Re: Predicate Not Defined (Porting ALS to LPA)
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Date: Mon, 5 Dec 1994 12:43:51 GMT
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Jay Margolis (jem@mba.com) wrote:

: I am porting a prolog program from ALS prolog to LPA Prolog.  In ALS,
: when a term is found on the right side of the horn clause that is
: not defined, it assumes failure, and backtracks.  But in LPA Prolog,
: it gets a run-time error: predicate not defined.

Have you tried declaring the term as dynamic?

:- dynamic term/arity.


--
        ______________________________________________________________
       / Mario Moreira         Centro de Estudos de Telecomunicacoes /
      / mesmam@di.uminho.pt                        Portugal Telecom //
     / moreira@smtpdos.cet.pt                    Aveiro - Portugal //
    / http://alfa.di.uminho.pt/~mesmam/     Universidade do Minho //
   /_____________________________________________________________//
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