Submission for slug-info

[daemon@potomac]

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From: daemon@potomac
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Subject: Submission for slug-info
Message-ID: <150@potomac.dc.ads.com>
Date: 21 Jan 87 02:59:27 GMT
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Path: potomac!daemon
From: John C. Akbari <AKBARI@CS.COLUMBIA.EDU>
Newsgroups: slug-info
Subject: operators in symbolics prolog
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Date: 20 Jan 87 21:02:29 GMT
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having some difficulties with symbolics prolog.  any hints on the foolowing?



/**********************************************************************
freely yanked from:
Bratko, Ivan.  _PROLOG Programming for Artificial Intelligence._
Addison-Wesley, 1986.
**********************************************************************/

% p. 82

:- op(800, xfx, <===>).
:- op(700, xfy, v).
:- op(600, xfy, &).
:- op(500, fy, ~).

% ~(A & B) <===> ~A v ~B.


traps with a warning about changing a read-table binding, then says that
the predicate (:prolog-predicate <===> 2) is undefined.

---
running rel 6.1 on a 3670.

	ad...THANKS...vance!

john c akbari

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