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![]() | Pack logtalk -- logtalk-3.81.0/examples/design_patterns/structural/proxy/SCRIPT.txt |
This file is part of Logtalk https://logtalk.org/ SPDX-FileCopyrightText: 1998-2023 Paulo Moura <pmoura@logtalk.org> SPDX-License-Identifier: Apache-2.0
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
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% start by loading the design pattern sample implementations:
| ?- logtalk_load(design_patterns('structural/proxy/loader'))
.
...
% first, lets create a old enough driver, no other than % Mr. Magoo itself (pedestrians be aware!):
| ?- driver::new(magoo, 'Mr. Magoo', 87)
.
yes
% in some of the cartoons, Mr. Magoo appears to be driving % a 1929 Packard Model 645 touring car; we can define the % car as a static object in the source file or create it % dynamically:
| ?- create_object(packard_645, [extends(car)], [], [])
.
yes
% then we check, using the proxy object, that the driver % can actually drive the car:
| ?- car_proxy(packard_645, magoo)
::drive.
Car has been driven! yes
% now, lets create a driver that is just too young, one of % the children that Mr. Magoo sometimes babysits:
| ?- driver::new(wheeler, 'Wheeler', 7)
.
yes
% then we check, using the proxy object, that the child % is effectively not allowed to drive the car:
| ?- car_proxy(packard_645, wheeler)
::drive.
Sorry, Wheeler is too young to drive! yes