From jcabrera@dis.ulpgc.es  Wed Nov 22 20:10:12 2000
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Date: Wed, 22 Nov 2000 18:42:58 +0000
From: Jorge Cabrera =?iso-8859-1?Q?G=E1mez?= <jcabrera@dis.ulpgc.es>
Organization: Grupo de Inteligencia Artificial y Sistemas
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To: prolog@swi.psy.uva.nl
Subject: About unification
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Hi,

Possibly it's a stupid question, but can someone explain this behavior in
unification:
(using swi prolog 3.3.10)

?-  -A = -(3).
A = 3
Yes

?- -A = -3.
No

Is it the right behavior?.

The only explanation I can think of is how the term '-A' is treated internally,
as shown using display/1.

?- display(-A = -3).
=(-(_G237), -3)
A = _G237
Yes

Thanks in advance.

JORGE.

