================================================================ Logtalk - Open source object-oriented logic programming language Release 2.30.7 Copyright (c) 1998-2007 Paulo Moura. All Rights Reserved. ================================================================ % start by loading the example and the required library files: | ?- logtalk_load(roots(loader)). ... % some queries dealing with instance/class hierarchies: | ?- object::ancestors(Ancestors). Ancestors = [class, abstract_class, object] Yes | ?- class::instances(Instances). Instances = [object, abstract_class, class] Yes | ?- class::superclass(Super). Super = abstract_class ; Super = object ; No