Path: utzoo!mnetor!uunet!munnari!mulga!zs
From: zs@mulga.oz (Zoltan Somogyi)
Newsgroups: comp.lang.prolog
Subject: deterministic predicates
Message-ID: <2714@mulga.oz>
Date: 28 Apr 88 01:27:45 GMT
Reply-To: zs@mulga.UUCP (Zoltan Somogyi)
Organization: Comp Sci, Melbourne Uni, Australia
Lines: 19


voda@ubc-cs (Paul Voda) writes:
> [In Trilogy] the system checks that all calls to 'preds', i.e. to the
> true backtracking predicates are enclosed in an all (min, one) solution
> construct, that there are no values returned through an "or" and
> that there are no symbolic (logic) variables with constraints used
> (except enclosed in all,min one constructs).

I have a different view: determinacy should be a property of the predicate
and its mode[s]. I have a paper on a closely related subject which dwells
on this issue at length. It is

Zoltan Somogyi: "Stability of logic programs: how to connect don't-know
nondeterministic logic programs to the outside world", Technical Report 87/11,
Department of Computer Science, University of Melbourne, Australia.

If you want a copy, drop me a line.

						Zoltan.