Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!seismo!rpics!wup
From: wup@rpics.RPI.EDU (Peter Y.F. Wu)
Newsgroups: comp.lang.prolog
Subject: Re: Prolog debugging
Message-ID: <737@rpics.RPI.EDU>
Date: Mon, 2-Feb-87 11:15:18 EST
Article-I.D.: rpics.737
Posted: Mon Feb  2 11:15:18 1987
Date-Received: Sat, 7-Feb-87 14:36:58 EST
References: <445@primerd.uucp>
Lines: 13
Summary: Flag undefined predicates...

In article <445@primerd.uucp>, bob@primerd.uucp writes:
> I'd like to hear about problems people have had...

Typo is a common mistake.  When that happens with the functor name of
a predicate, it results in undefined predicates in the Prolog program.
It may be nice for a Prolog system to *optionally* flag undefined
predicates so that one does not have to trace it all the way to realize
it is a typo in the functor name.  It has to be optional since undefined
predicate may be a deliberate feature to generate failure.

Peter Y.F. Wu
wup@csv.rpi.edu
...seismo!rpics!wup