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This file is part of Logtalk <https://logtalk.org/>  
Copyright 1998-2019 Paulo Moura <pmoura@logtalk.org>

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
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    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
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Design pattern:
	Strategy

Description:
	"Define a family of algorithms, encapsulate each one, and make them
	interchangeable. Strategy lets the algorithm vary independently of
	from clients that use it."

This pattern can be used with both classes and prototypes.

The sample implementation uses prototypes and dynamic object predicates
to allow the strategy to be changed dynamically at runtime.
