[boost] Re: any interest in Boost Unification and Backtrackinglibrary (UBL)?

From: David Abrahams (dave_at_[hidden])
Date: 2004-09-14 08:34:11

"G. Wang" <visionsoft_at_[hidden]> writes:

>> I'm interested.  My first question would be, "what kinds of real
>> problems can I solve better/more easily/more expressively with UBL
>> than with approaches we already have available?"  That's the test that
>
> UBL allows you to write Prolog-like code directly inside C++. The current
> Prolog is modeled directly to the Prolog standard. So IMHO your question is
> equivalent to
>
> "what kind of real problems can I solve better/more easily/more expressively
> with Prolog than with approaches we already have available in C++?"
>
> Prolog is the preferred language in the field of AI, expert systems,
> business logics, etc. There are lots of discussions about why Prolog
> is better in those areas than traditional procedure-oriented or
> object-oriented languages. I don't think that I can cover the
> reasons in just a few paragraph.

It's not quite equivalent.  You have to ask whether a _C++ Program_
would benefit enough from that paradigm to make it worthwhile to
suffer the imperfect expression of it that you can achieve in a
library.

FC++ is modeled directly on Haskell, and I fully believe that there
are real problems that one would choose to solve first in Haskell, but
that didn't turn out to mean that a translation into C++ could provide
compelling advantages to people already writing software in C++.

Please take this question seriously.  We all felt really badly about
not accepting FC++ into Boost at the end of its formal review, which
was a substantial emotional/time investment for its author.  It was a
really interesting library, but it seemed to fail a crucial
utility/practicality test.  I don't want something like that to
happen to you.

This post (http://article.gmane.org/gmane.comp.lib.boost.devel/109639)
begins to give me some assurance, but it would be very helpful to hear
more from you.

-- 
Dave Abrahams
Boost Consulting
http://www.boost-consulting.com