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current_predicate(?PredSpec)
Succeeds if PredSpec is a visible predicate defined by the user, or a
visible library predicate.
- ?PredSpec
- Expression of the form Atom/Integer or variable.
Description
Used to check that PredSpec is a user or library predicate visible from
the caller module, or else to return on backtracking all the current
visible predicates.
Fail Conditions
Fails if PredSpec is not a visible (user or library) predicate.
Resatisfiable
Yes.
Exceptions
- (5) type error
- PredSpec is instantiated, but not to the form Atom/Integer.
Examples
Success:
[eclipse]: current_predicate(X/Y).
X = intersection
Y = 3 More? (;)
yes.
[eclipse]: current_predicate(X).
X = (^) / 2 More? (;)
X = intersection / 3 More? (;)
X = subtract / 3 More? (;)
X = append / 3 More? (;)
yes.
[eclipse]: [user].
p.
user compiled 28 bytes in 0.00 seconds
yes.
[eclipse]: current_predicate(p/0).
yes.
Fail:
current_predicate(assert/1).
Error:
current_predicate(a/a). (Error 5).
See Also
current_module_predicate / 2, current_built_in / 1, is_predicate / 1, get_flag / 3