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fork(+Max, ?I)

Succeeds for all integers I between 1 and Max. The solutions are generated in parallel.

Max: Integer
I: Variable or Integer

Description

Generates in parallel the integers between 1 and a given maximum Max. The order of solutions is unspecified. For every value of Max, this predicate behaves as if defined by

   :- parallel fork/2.
   fork(Max, Max).
   ...
   fork(Max, 2).
   fork(Max, 1).

Operationally, the advantage of fork/2 compared to a recursive definition like

   :- parallel bfork/2.
   bfork(Max, Max).
   bfork(Max, I) :- Max>1, Max1 is Max-1, bfork(Max1, I).

is that fork/2 creates only a single wide choice point instead of Max binary ones. This improves efficiency, especially for parallel execution.

Fail Conditions

Fails if Max is less than 1.

Resatisfiable

Yes.

Exceptions

(4) instantiation fault: Max is not instantiated.
(5) type error: Max is not an integer.

Examples