Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!elroy.jpl.nasa.gov!sdd.hp.com!hplabs!otter.hpl.hp.com!otter!sfk
From: sfk@otter.hpl.hp.com (Steve Knight)
Newsgroups: comp.lang.prolog
Subject: Re: Re: Garbage collecting names in Prology
Message-ID: <1600028@otter.hpl.hp.com>
Date: 17 Apr 91 11:01:53 GMT
References: <1991Apr12.084444.7866@swift.cs.tcd.ie>
Organization: Hewlett-Packard Laboratories, Bristol, UK.
Lines: 14

> A related question is whether Poplog Prolog has the builtin 'current_functor',
> and if it has, what does current_functor give you?

It gets functors named in 'predicate positions' and not those named
in 'argument positions'.  Therefore its behaviour doesn't change across a 
GC -- at the expense of being unable to easily find some other names.

> It seems therefore that implementers are between a rock and a hard place in
> this case, hence my question in the first place.

I'm inclined to agree.  But on the other hand it seems like a fairly useless
predicate so implementors can find sub-solutions without much complaint.

Steve