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From: ok@goanna.cs.rmit.oz.au (Richard A. O'Keefe)
Newsgroups: comp.lang.prolog
Subject: Re: The Craft of Prolog, pp. 126-30
Message-ID: <4227@goanna.cs.rmit.oz.au>
Date: 9 Nov 90 01:31:06 GMT
References: <4492@swi.swi.psy.uva.nl>
Organization: Comp Sci, RMIT, Melbourne, Australia
Lines: 15

In article <4492@swi.swi.psy.uva.nl>, anjo@swi.psy.uva.nl (Anjo Anjewierden) writes:
> I'm about to conclude every program in ``The Craft of Prolog'' will
> run on Prolog implementations with 14-bit integer arithmetic.  Is
> this right?

Probably not.  The Prolog system I used with 14-bit integers was
PDP-11 Prolog, and if I remember correctly that didn't include a sign bit.
(Which is why library(long) exists.  I had "improved" a program to do some
clever things with arithmetic, and it was easier to implement bignums than
to figure out how the program _used_ to work.)
Another reason for doubting this is that I have been sent some errata; if
there's any interest I could collate and post them.
-- 
The problem about real life is that moving one's knight to QB3
may always be replied to with a lob across the net.  --Alasdair Macintyre.