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is_built_in(+PredSpec)

Succeeds if PredSpec is a system built-in predicate.

+PredSpec: Term of the form Atom/Integer.

This built-in predicate is obsolete!

Description

Used to test whether PredSpec is a ECLiPSe built-in predicate.

This predicate only succeeds for a PredSpec which is known to be a built-in. Undefined Predspec's raise an exception.

Fail Conditions

Fails if PredSpec is not a built-in predicate.

Resatisfiable

No.

Exceptions

(4) instantiation fault: PredSpec is not fully instantiated.
(5) type error: PredSpec is not in the format Atom/Integer.
(60) referring to an undefined procedure: PredSpec is not a defined procedure.

Examples

Success:
   is_built_in(nl/0).
   is_built_in(write/1).

Fail:
   is_built_in(append/3). % append/3 is a library
                          % predicate, not a built-in.
Error:
   is_built_in(X).           (Error 4).
   is_built_in(a/X).         (Error 4).
   is_built_in(a).           (Error 5).
   is_built_in(1).           (Error 5).
   is_built_in(undefined/0). (Error 60).