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From: "Bernd Fischer" <fisch@ptolemy.arc.nasa.gov>
To: "SWI Prolog (list)" <prolog@swi.psy.uva.nl>
Date: Thu, 22 Feb 2001 15:17:15 -0800
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Subject: [SWIPL] choicepoints from flag/3

Hi,

using flag/3 leaves my with unwanted (and redundant) choicepoints which I
can't cut away. Look at:

1 ?- flag(test, _, 1).

Yes
2 ?- flag(test, X, X).

X = 1 ;

No.
3 ?- once(flag(test, X, X)).

X = 1 ;

No.


Is there any way around it? Or do I understand something fundamentally wrong
here?

-- fisch

--
------------------------------------------------------------------------------
Bernd Fischer                             Automated Software Engineering Group
RIACS, NASA Ames Research Center                    fisch@ptolemy.arc.nasa.gov
M/S 269-2                               http://ase.arc.nasa.gov/people/fischer
Moffett Field, CA 94035, USA             +1(650)604-2977  fax 4036  rm 269-239

