Newsgroups: comp.lang.prolog
Path: cantaloupe.srv.cs.cmu.edu!das-news2.harvard.edu!news2.near.net!satisfied.elf.com!news.mathworks.com!uunet!munnari.oz.au!cs.mu.OZ.AU!munta.cs.mu.OZ.AU!fjh
From: fjh@munta.cs.mu.OZ.AU (Fergus Henderson)
Subject: Re: Nature of Prolog extensions (was: Question about
Message-ID: <9503401.19705@mulga.cs.mu.OZ.AU>
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Organization: Computer Science, University of Melbourne, Australia
References: <3g637b$560@news.cs.tulane.edu> <3gkqb6$et8@hustle.rahul.net>
Date: Thu, 2 Feb 1995 14:17:15 GMT
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Bill Hogan <bhogan@rahul.net> writes:

>  But I am not in favor of getting rid of "!" because I think we will
>always need some way to say "in which case there is no further 
>question".

We can find better ways of saying that.

Prolog was supposed to be PROgramming in LOGic.
Somewhere along the line, the logic seems to have gotten lost 
amoungst the hacks.  Constructs like the cut have become ingrained
as a fundamental part of Prolog.

But it doesn't have to be like that.  Languages like Goedel have
shown that we can have an almost pure logic language, and Mercury
shows that it can be completely pure - and yet more efficient than Prolog.
With modern compiler technology, the Prolog hacks actually _impair_
efficiency by making optimization more difficult.

--
Fergus Henderson - fjh@munta.cs.mu.oz.au
