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This file is part of Logtalk https://logtalk.org/ SPDX-FileCopyrightText: 1998-2023 Paulo Moura <pmoura@logtalk.org> SPDX-License-Identifier: Apache-2.0

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Design pattern: Proxy

Description: "Provide a surrogate or placeholder for another object to control access to it."

This pattern can be used with both classes and prototypes.

Proxy objects are simple to implement. We can have the proxy object implementing a protocol, shared with the real object, that specifies only the predicates that the proxy object redefines. This allows the using the forward/1 handler to delegate all other messages to the real object. When the proxy object is expected to implement the full protocol of the real object, an alternative solution is for the proxy object to inherit privately from the real object and overriding (or specializing) only those predicates that motivated the use of a proxy.