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From: roland@sics.se (Roland Karlsson)
Newsgroups: comp.lang.prolog
Subject: Re: '->' operator
Message-ID: <1991Jan10.122652.20852@sics.se>
Date: 10 Jan 91 12:26:52 GMT
References: <291@valverde.cs.utexas.edu>
	<1991Jan4.030918.24996@athena.cs.uga.edu>
	<1991Jan4.061142.26941@athena.cs.uga.edu> <6402@munnari.oz.au>
	<1991Jan10.103521.2278@sics.se>
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Organization: Swedish Institute of Computer Science, Kista
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In-Reply-To: dan@sics.se's message of Thu, 10 Jan 91 10:35:21 GMT


Incredible.  I am amazed.  try this four "equivalent" predicates.

p1   :- ((/*true,*/(true->write(1)      )) ; write(2)), fail.
p12  :- ((  true,  (true->write(1)      )) ; write(2)), fail.
p12a :- ((/*true,*/(true->write(1);false)) ; write(2)), fail.
p12b :- ((  true,  (true->write(1);false)) ; write(2)), fail.

--
Roland Karlsson
SICS, PO Box 1263, S-164 28 KISTA, SWEDEN	Internet: roland@sics.se
Tel: +46 8 752 15 40	Ttx: 812 61 54 SICS S	Fax: +46 8 751 72 30