Re: Prolog programming job?

On Sat, 23 Sep 2006, bart demoen wrote:
On Sat, 23 Sep 2006 01:20:58 +0200, Nameless wrote:

However, this is not to say that Erlang more than other
functional languages was significantly _influenced_ by
Prolog. It simply means that Prolog was taken in use as
a prototyping tool -- and a fine one it is.

I think you should have a look at the history of Erlang and
appreciate the fact that Erlang at first had commonalities with
Prolog (it was more than just being implemented by a Prolog interpreter).
Sure, quite soon, the authors decided to take out backtracking and logical
variables. But that does not mean Erlang was not influenced heavily by
Prolog.

Erlang actually originated as little more than a sugared version of the
committed choice concurrent logic language which itself went under
various names (Parlog, Strand, Flat Concurrent Prolog, KL1, Guarded Horn Clauses etc) as essentially the same idea was being developed by several research teams who never managed to agree on a common language, but they differed only on very minor details. It was these languages which had already
taken out backtracking and two-way unification, Erlang didn't have to do it,
it used the conclusions the committed choice logic language people had
already come to on how to map a language which looked like a logic
programming language onto concurrent processing. I'm pretty sure this
debt is more openly acknowleged in some of the early Erlang work.
The syntax changes needed to make these language look like functional
rather than logic languages was very minor, and the other change was to
make the concurrency under more explicit programmer control rather than left completely to the underlying implementation, something the committed choice logic language people were toying with anyway.

The Erlang people decided that with logic programming widely seen as
a "failure" following the 5th generation project hype and inevitable
failure to live up to the hype, it would make better marketing to sell
it as a functional rather than a logic language. Thus they airbrushed out
its logic programming background in their later work.

Matthew Huntbach

.

Relevant Pages

  • Re: Mainstreaming Prolog a Pragmatic Approach?
    ... experience is that Prolog is an incredibly useful language for virtually all ... often than not end up using Prolog. ... I think you're right when you question whether logic programming really ...
    (comp.lang.prolog)
  • Re: An even more basic question...
    ... My task was to represent these rules in Prolog, and to write an engine which, given a client's total position, could find the way of pairing its components so as to satisfy the rules with the minimum total margin requirement. ... present-day ISO Prolog is not co-extensive with the concept of Prolog -- and Prolog is not a "language" is the abusive sense in which that term is misapplied to deterministic stepwise-imperative computing notations. ... TOPIC: PROGRAMMING ... adapted to your particular scheduling problem, ...
    (comp.lang.prolog)
  • Re: An even more basic question...
    ... relatively recent standardization of prolog, how come the prolog community, ... applicable as a standalone language for product development. ... for example - noone expects SQL to ... programming language, and in time more sophisticated operational ...
    (comp.lang.prolog)
  • Re: Minsky still posting
    ... >> they seem to me significant features of its own. ... > the functiomal langauges than used with Prolog. ... operator in an imperative language. ... > part of the logic programming core of Prolog. ...
    (comp.lang.prolog)
  • Re: Mainstreaming Prolog a Pragmatic Approach?
    ... What you can do in one language, you can do in another, one ... So that's no more unique to Prolog than anything else. ... Sure you can implement depth-first backtracking in C, ... language I would choose to use for any significant piece of programming. ...
    (comp.lang.prolog)