Defining var(X).

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Article #704

#704

From: bhyde
Date: Thu, 26 Jun 1986 20:15

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The prolog that I use loads a library of standard
definitions upon start up.  I got to wondering 
what things are truly primative in prolog.  Somebody
asked recently if the predicate var can be defined
"logically."  How's this?
  var(X) :- not(not(X=1)), not(not(X=2).

Now can we define the operator "=="?  Notable is
that:
   : X == X?
   true.
   : X == Y?
   false.
At least in some implementations.

    - ben hyde, cambridge mass.

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From: bhyde@inmet.UUCP
Newsgroups: net.lang.prolog
Subject: Defining var(X).
Message-ID: <5300003@inmet>
Date: Thu, 26-Jun-86 16:15:00 EDT
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Posted: Thu Jun 26 16:15:00 1986
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