private/1
private(Predicate) private(Predicate1, Predicate2, ...) private([Predicate1, Predicate2, ...])Declares private predicates. A private predicate can only be called from the object containing the private directive.
private(+predicate_indicator_term)
:- private(counter/1). :- private(init/1, free/1). :- private([data/3, key/1, keys/1]).