nl/1 in SICStus prolog

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Article #19

#19

From: Roland Paterson-Jones
Date: Thu, 29 Oct 1992 15:49

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While running a prolog program written in SICStus, our SBProlog3.1 whinged
about the predicate nl/1:

> process_back_arcs:-
>     retract(arc(X,Y,back)),
>     display('processing a new back'), nl(user_output),
>     ( node(Y,I_Y,_) -> true ),	^^^^^^^^^^^^^^^
>     find_cycles([Y],X,I_Y,[Y]),
>     process_back_arcs.

What is this intended to do, and what is the significance of the atom
'user_output'?

--
Roland P-Jones			aka roland@uctcs.cs.uct.ac.za
University of Cape Town		 or roland@sun-2.cs.uct.ac.za
South Africa

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Path: arc1-ca.pugleaf.net!sparky!uunet!kithrup!hoptoad!pacbell.com!sgiblab!sdd.hp.com!usc!elroy.jpl.nasa.gov!ames!sun-barr!olivea!charnel!psgrain!hippo!shrike.und.ac.za!casper.cs.uct.ac.za!sun-2!roland
From: roland@sun-2.cs.uct.ac.za (Roland Paterson-Jones)
Newsgroups: comp.lang.prolog
Subject: nl/1 in SICStus prolog
Summary: does what?
Message-ID: <roland.720373791@sun-2>
Date: 29 Oct 92 15:49:51 GMT
Sender: news@casper.cs.uct.ac.za (news)
Organization: Computer Science Department, University of Cape Town
Lines: 17