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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

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

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

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This is a minimal example illustrating the use of the uses/1 directive to experiment with different object implementations of the same protocol when using explicit message-sending. The main idea is to have a single source line that can be edited to switch between different implementations as all message-sending calls would be written using the object alias. This is an alternative to accomplish the same goal by using a uses/2 directive and implicit message-sending. Note that both alternatives allow compiling the code in optimized mode to take advantage of static binding for the message-sending calls.

This example also illustrates defining an alias for an object defined at runtime using a parameter variable.