From p.singleton@keele.ac.uk  Wed Apr 12 16:12:49 2000
Received: from cmailg5.svr.pol.co.uk (cmailg5.svr.pol.co.uk [195.92.195.175])
	by swi.psy.uva.nl (8.9.3/8.9.3) with ESMTP id QAA28977
	for <prolog@swi.psy.uva.nl>; Wed, 12 Apr 2000 16:12:49 +0200 (MET DST)
Received: from modem4294967194.advice.dialup.pol.co.uk ([195.92.0.102] helo=keele.ac.uk)
	by cmailg5.svr.pol.co.uk with esmtp (Exim 3.13 #0)
	id 12fNtK-0003It-00
	for prolog@swi.psy.uva.nl; Wed, 12 Apr 2000 15:13:15 +0100
Message-ID: <38F4844E.C86E716E@keele.ac.uk>
Date: Wed, 12 Apr 2000 15:12:30 +0100
From: Paul Singleton <p.singleton@keele.ac.uk>
Organization: SmartArts Computing Consultancy
X-Mailer: Mozilla 4.7 [en] (WinNT; I)
X-Accept-Language: en
MIME-Version: 1.0
To: SWI Prolog <prolog@swi.psy.uva.nl>
Subject: modules and foreign code
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit

I'm having a go at adding module support to JPL, and I have a few
questions (about SWI-Prolog):

 1) does foreign code _always_ have a context module?
    e.g. if we start the Prolog engine from C?

 2) is the null atom (or empty C string) a valid module name?

 3) does PL_pred(f,NULL) reliably (for valid f) refer to the
    prevailing context module?

 3a) is PL_pred( f, PL_context()) better in any way?

 4) does PL_predicate( name, arity, NULL) reliably refer to the
    prevailing context module?

 4a) is PL_predicate( name, arity,
PL_atom_chars(PL_module_name(PL_context())))
     better in any way?!

Paul Singleton

