Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!mcsun!ukc!dcl-cs!gdt!gdr.bath.ac.uk!ccsdgdc
From: ccsdgdc@gdr.bath.ac.uk (Douglas Clark)
Newsgroups: comp.lang.prolog
Subject: elementary problem (I hope)
Message-ID: <1990Mar9.095655.4191@bath.ac.uk>
Date: 9 Mar 90 09:56:55 GMT
Sender: ccsdgdc@bath.ac.uk (Douglas Clark)
Organization: Bath University Computing Services, UK
Lines: 15


A user has been asking me how to write synonyms in Prolog. Being ignorant
I have no idea. It is obvious why the natural

father(X):-male(X).
male(X):-father(X).
father(fred).

fails. But I cannot find a substute that works. Some way of eliminating
the repetitive backtracking. Help would be appreciated.
-- 
Douglas Clark                                   Voice : +44 225 826039
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