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current_built_in(?PredSpec)

Succeeds if the predicate defined by PredSpec is a visible built-in predicate.

PredSpec: Expression of the form Atom/Integer or variable.

Description

Used to check that PredSpec is a built-in predicate visible from the context module, or else to return on backtracking all the visible built-in predicates.

Modes and Determinism

current_built_in(++) is semidet
current_built_in(-) is nondet

Modules

This predicate is sensitive to its module context (tool predicate, see @/2).

Fail Conditions

Fails if the predicate defined by PredSpec is not a visible built-in predicate

Exceptions

(5) type error: PredSpec is instantiated, but not to the form Atom/Integer.

Examples

Success:
     [eclipse]: current_built_in(X/Y),!.
     X = findall
     Y = 3
     yes.

     [eclipse]: current_built_in(X).
     X = findall / 3     More? (;)
     X = ! / 0     More? (;)
     X = delayed_goals / 1     More? (;)
     X = delayed_goals / 2     More? (;)   % type <cr>
     yes.
Fail:
     current_built_in(assertz/1).
     current_built_in(reverse/2).

     [eclipse]: [user].
      p.
      user compiled 28 bytes in 0.00 seconds
     yes.
     [eclipse]: get_flag(p/0, type, T).
     T = user
     yes.
     [eclipse]: current_built_in(p/0).
     no.
Error:
     current_built_in(a/a).         (Error 5).