b77427df89
git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@211 b08c6af1-5177-4d33-ba66-4b1c6b8b522a
130 lines
2.1 KiB
Plaintext
130 lines
2.1 KiB
Plaintext
=================================================================
|
|
Logtalk - Object oriented extension to Prolog
|
|
Release 2.9.1
|
|
|
|
Copyright (c) 1998-2001 Paulo Moura. All Rights Reserved.
|
|
=================================================================
|
|
|
|
|
|
% print the (public and protected) interface of each class:
|
|
|
|
| ?- (object, abstract_class, class)::print.
|
|
|
|
Object: object
|
|
|
|
interface:
|
|
new/1
|
|
delete/1
|
|
instances/1
|
|
metaclass/0
|
|
abstract_class/0
|
|
strict_instance/0
|
|
print/0
|
|
|
|
Object: abstract_class
|
|
|
|
interface:
|
|
new/1
|
|
delete/1
|
|
instances/1
|
|
metaclass/0
|
|
abstract_class/0
|
|
strict_instance/0
|
|
print/0
|
|
|
|
Object: class
|
|
|
|
interface:
|
|
new/1
|
|
delete/1
|
|
instances/1
|
|
metaclass/0
|
|
abstract_class/0
|
|
strict_instance/0
|
|
print/0
|
|
|
|
yes
|
|
|
|
|
|
% class is the metaclass of all classes:
|
|
|
|
| ?- class::instances(Instances), class::metaclass.
|
|
|
|
Instances = [class,abstract_class,object]
|
|
yes
|
|
|
|
|
|
% create an abstract_class, check it and print its interface:
|
|
|
|
| ?- abstract_class::new(ac), ac::abstract_class, ac::print.
|
|
|
|
Object: ac
|
|
|
|
interface:
|
|
metaclass/0
|
|
abstract_class/0
|
|
strict_instance/0
|
|
print/0
|
|
|
|
yes
|
|
|
|
|
|
% try to create an instance of the abstract class:
|
|
|
|
| ?- ac::new(i).
|
|
|
|
uncaught exception: error(existence_error(predicate_declaration,new(i)),ac::new(i),user)
|
|
|
|
|
|
% create a new instantiable class and print its interface:
|
|
|
|
| ?- class::new(c), c::print.
|
|
|
|
Object: c
|
|
|
|
interface:
|
|
new/1
|
|
delete/1
|
|
instances/1
|
|
metaclass/0
|
|
abstract_class/0
|
|
strict_instance/0
|
|
print/0
|
|
|
|
yes
|
|
|
|
|
|
% create an instance of the new class:
|
|
|
|
| ?- c::new(i), c::instances(Instances).
|
|
|
|
Instances = [i]
|
|
yes
|
|
|
|
|
|
% because c does not declare any predicates, its instances have no interface:
|
|
|
|
| ?- i::current_predicate(Predicate).
|
|
|
|
no
|
|
|
|
|
|
% create an instance of object, root of the inheritance graph, and print its interface:
|
|
|
|
| ?- object::new(j), j::print.
|
|
|
|
Object: j
|
|
|
|
interface:
|
|
strict_instance/0
|
|
print/0
|
|
|
|
yes
|
|
|
|
|
|
% delete the dynamic objects that we created:
|
|
|
|
| ?- c::delete(i), class::delete(c), abstract_class::delete(ac), object::delete(j).
|
|
|
|
yes
|