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Copyright 1998-2021 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.
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    http://www.apache.org/licenses/LICENSE-2.0

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Design pattern:
	Bridge

Description:
	"Decouple an abstraction from its implementation so that the two
	can vary independently."

This pattern can be used with both classes and prototypes.

In this sample implementation, we use classes for representing the
abstraction part of the pattern and prototypes for the implementation
part. As discussed in the pattern description, the instances in the
abstraction hierarchy use object composition to refer to and delegate
operations to the implementation hierarchy objects.
