Re: Ann: SWI-Prolog 7.1.0

On 11/27/2013 06:41 AM, Richard A. O'Keefe wrote:
> Look, Jan, the next thing I say here may sound offensive.
> I don't mean it to be.

If I was that easily offended, I would have stopped working
on SWI-Prolog long ago :-)

> The changes you are making to SWI Prolog make it more like
> Javascript and less like a logic programming language.

"More like Javascript", I agree.  "Less like a logic programming",
I don't agree.  None of these changes change anything to the
inference mechanism.  They only add a few new data types and
some syntax.

> Now from some of the things you said in the announcement, it sounds
> to me as though you_intend_  SWI Prolog to me more like Javascript,
> and I think you are much more concerned about making SWI Prolog
> into a valuable tool for Web developers who aren't terribly
> interested in logic programming as such than in "traditional"
> users of Prolog.  With the exception of good support for strings
> and psi-terms (proper LIFE-like psi-terms), I don't think any of
> the changes discussed in this thread actually do that.  And good
> support for strings and (proper LIFE-like) psi-terms is also good
> for "traditional" users of Prolog, especially NLP.

I have not found time to study psi-terms in detail.  From the
brief summary posted here, I have the impression that the maps/dicts/...
can evolve to psi-terms.  If I have made choices that prevent this,
please warn me.

> I may seem to contradict myself here, because I don't like
> functor/3 and (=..)/2 being broken.  Psi-terms are a big enough
> benefit to justify that, and we have the LIFE documentation to
> tell us how to deal with it.  But I don't see any indication of
> LIFE being taken as a guide, and again this is compatible with
> the changes being driven by the tastes of Web developers rather
> than say NLP programmers.

It is hard to deny that the extensions are mostly influenced
by the topics to which I'm most closely related.  That should
not exclude other domains, but others should do the work to
get their domain better supported.  I would not have implemented
attributed variables, big integers and rational numbers without
people bagging (or for some of this paying) for them.

	Cheers --- Jan


> I note that LIFE psi-terms do admit a compound term which I'll
> write as f(...) which doesn't have any arguments_yet_  but also
> doesn't definitely have_no_  arguments; psi-terms are
> open to extension.  So that doesn't necessitate an f() -vs- f
> distinction.