Newsgroups: comp.lang.scheme
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From: mad@math.keio.ac.jp (MAEDA Atusi/=?ISO-2022-JP?B?GyRCQTBFREZYO0obKEI=?=)
Subject: Re: scheme vs prolog
In-Reply-To: mark rostron's message of Tue, 29 Oct 1996 14:07:04 -0600
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>>>>> "mark" == mark rostron <mobile@visi.com> writes:
In article <327663E8.52C5@visi.com> mark rostron <mobile@visi.com> writes:

    mark> I dont understand scheme or lisp very well and so am in no position to
    mark> make comparisons. However, my observation is that you tend to spend a
    mark> lot of time writing machines which provide the sort of facilities which
    mark> prolog already provides i.e. non-determinism, continuations,
    mark> backtracking.

When I write programs in prolog and prolog-like languages, I spend
most of my time avoiding unwanted non-determinism and backtracking
(i.e. inserting cut operators here and there).

Prolog's `backtrack by default' behavior is pain because I need simple
loop or simple if-then construct far more frequently than brute-force
exhaustive search.

I would like prolog if it had made backtracking optional and made
deterministic call the default.  I'd rather use KL1, a parallel logic
programming language which doesn't have backtracking.  KL1 and other
commited-choice languages have much cleaner semantics, too.

Actually, I rarely need brute-force search (by backtracking) except
for 10-lines-long toy programs.  And coding exhaustive search is
trivial anyway.  It had better be left out from language feature, if
the language has rich enough control-flow primitives.

				--mad
