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Logtalk - Object oriented extension to Prolog
Release 2.28.2
Copyright (c) 1998-2006 Paulo Moura. All Rights Reserved.
% start by loading the example:
| ?- logtalk_load(aliases(loader)).
...
% check the object square(_) public protocol:
| ?- square(_)::current_predicate(Predicate).
Predicate = side/1 ;
Predicate = width/1 ;
Predicate = height/1 ;
Predicate = area/1
yes
% test the side/1 alias:
| ?- square(2)::side(Side).
Side = 2
| ?- square(2)::predicate_property(side(_), Property).
Property = public ;
Property = static ;
Property = declared_in(rectangle(_G264, _G265)) ;
Property = defined_in(rectangle(_G297, _G298)) ;
Property = alias(width(_G182))
| ?- square(2)::predicate_property(width(_), Property).
Property = declared_in(rectangle(_G262, _G263)) ;
Property = defined_in(rectangle(_G293, _G294))
% check the object circle(_) public protocol:
| ?- circle(_)::current_predicate(Predicate).
Predicate = r/1 ;
Predicate = rx/1 ;
Predicate = ry/1 ;
% test the r/1 alias:
| ?- circle(3)::r(Radius).
Radius = 3
| ?- circle(3)::predicate_property(r(_), Property).
Property = declared_in(ellipse(_G266, _G267)) ;
Property = defined_in(ellipse(_G299, _G300)) ;
Property = alias(rx(_G177))
| ?- circle(3)::predicate_property(rx(_), Property).
Property = declared_in(ellipse(_G261, _G262)) ;
Property = defined_in(ellipse(_G292, _G293))