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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: Composite

Description: "Compose objects into tree structures to represent part-whole hierarchies. Composite lets clients treat individual objects and compositions of objects uniformly."

This pattern can be used with both classes and prototypes.

In this sample implementation of the pattern, we choose to use classes and object composition (i.e., composite objects will store the identifiers of the objects that are part of the composite). In the sample queries, we create the instances dynamically at runtime but we could also have defined (some or all) of the instances statically in the source file.