🚀 go-pugleaf

In article 28120@athena.cs.uga.edu, mcovingt@aisun3.ai.uga.edu (Michael Covington) writes:
>  - Efficiency of execution
>       (That's right, if you're using backtracking and unification then
>        your program will probably run as fast under Prolog as under any
>        other language.  We once ported a simple Prolog list processing
>        routine into Pascal as a test, and got a factor-of-14 *slowdown*!)

It is nice that People really do believe in Prolog, but there must be a mistake here.
The fact that you use unification and backtracking does not make your program
faster, it may simplify the algorithm, though. When one rewrites list processing
procedures to C, one certainly gets a significant speedup, maybe 3 - 10.
You must have dome something funny in your Pascal translation, or it was
a very slow Pascal. In fact it is unification, backtracking, and logical variables,
i.e. the particular Prolog features, that make it slower than other languages.
The current compiler technology moves towards eliminating this overhead by
recognizing deterministic code in place of backtrackable one, and assignments
and tests in place of the unification, but it will take some time till we get there.

--Micha

---
Micha Meier			------------------------------------------------
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