Path: utzoo!attcan!uunet!mcsun!ukc!icdoc!sappho!cdsm
From: cdsm@sappho.doc.ic.ac.uk (Chris Moss)
Newsgroups: comp.lang.prolog
Subject: Re: More fun with WG17
Message-ID: <1371@gould.doc.ic.ac.uk>
Date: 20 Nov 89 18:40:33 GMT
References: <2609@munnari.oz.au> <696@sce.carleton.ca> <2643@munnari.oz.au> <1359@gould.doc.ic.ac.uk> <2744@munnari.oz.au>
Sender: news@doc.ic.ac.uk
Reply-To: cdsm@doc.ic.ac.uk (Chris Moss)
Organization: Logic Group, Dept. of Computing, Imperial College, London, UK.
Lines: 53

In article <2744@munnari.oz.au> ok@mudla.cs.mu.OZ.AU (Richard O'Keefe) writes:
>  I will be
>very surprised indeed if the NZSI ever made any decision about Prolog as such
>at all.

No, Richard, I never claimed it did. Indeed I'd be surprised if it had.
Because it decided not to be a member of SC22 I assume Prolog followed by
default. 

>  "Priority" is a total red
>herring, here.  If we went by priority, I think we'd have to go for the
>Begriffschrift (sp?) -- I've been surprised that no-one has revived it as
>a "graphical Prolog".  Or GOLUX.  A standard is for a PRACTICAL purpose.

This is silly. Are you claiming that Edinburgh was the only practical Prolog
system around?

>The criterion which guides a standard is "what will maximise the practical
>utility of this standard?"  At the time that the BSI committee was formed,
>the answer was clear:  the Edinburgh branch of the Prolog family stood out
>in terms of number of implementations that were intended to be compatible,
>in terms of books in print or in progress, and in terms of public-domain
>software coded in that dialect (the DEC-10 Prolog library). 

I think this is a biased view. If one was to judge simply by the number
of sales, then probably in 1984 microProlog would have won hands down. As
you point out, Turbo would probably win now. Are either of these relevant?
Probably the only way in which Edinburgh was the clear winner then was in the
sales of Clocksin & Mellish's book, which is different in some ways
(e.g. operator definitions) from any widely used implementation.

Unfortunately, nobody did a serious survey then to find out what was most
widely acceptable, and so there was a lot of wrangling which, with hindsight,
was very destructive.  By the time a consensus emerged most of the good people
had quit the committees.

>Let's consider availability now, and see what it tells us about whether
>a Prolog standard should resemble Edinburgh Prolog, or Turbo Prolog, or
>Prolog III, or micro-PROLOG.

I was NOT arguing NOW in favour of any other basis for the standard. I was
talking about history and trying to explain to those who didn't know it why
there had been so many different points of view. I made my point of view quite
clear at the Seattle conference in 1988 and haven't changed it since, that I
believe that using the Edinburgh definition is the only way a standard will
be achieved. It has certainly been accepted in the English, Japanese and German
speaking worlds. I don't think the French have been won over. I've used it
almost exclusively for the last 3-4 years and we've switched in our teaching
here at Imperial College (this year has completed the transition).

So please don'tt make out I'm arguing for a position I don't hold.

Chris.