Re: trail stack, global stack

"blindsearch" <dpatte3@xxxxxxxxxxx> writes:
> Is there anyway to clean up the global and trail stacks during execution?

The classical trick, if your program doesn't need to backtrack (i.e., really
leaves no choice points), is the double negation:

foo :-
\+ \+ some_expensive_computation,
foo.

If you need to pass state around, it gets ugly:

foo(State0) :-
\+ \+ ( some_expensive_computation(State0, State1),
assert(saved_state(State1))
),
retract(saved_state(State)),
!,
foo(State).

--
mailto:jjk@xxxxxxx As the air to a bird, or the sea to a fish,
http://www.bawue.de/~jjk/ so is contempt to the contemptible. [Blake]
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.

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