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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.

To load this example and for sample queries, please see the SCRIPT.txt file.

This folder provides a classic set of plain Prolog benchmark programs and Logtalk wrappers for those programs. Loading this example and an individual plain Prolog benchmark allows us to evaluate the overhead of the implicit execution context argument that the Logtalk compiler adds to object (and category) predicates. Note that this old set of benchmarks don't cover all features of modern day Prolog and Logtalk programming (e.g., meta-predicates).

All plain Prolog programs define a top/0 predicate to run the benchmark. The Logtalk versions provide a top/0 public predicate.

Some of the benchmarks have dependencies on some built-in predicates that are not universal. But we load by default those benchmarks when their dependencies don't actually prevent running the top/0 predicate. See the loader.lgt and run.lgt files for details.

Note that some benchmark programs cannot be loaded when using some backend Prolog compilers due to portability issues. We decided to keep the original code as-is instead of modifying them to fix those issues. See the loader.lgt file for details.

The plain Prolog benchmark programs are often used and cited in scientific papers that discusses Prolog performance, available in public repositories, and public discussion forums. We copied them with permission from:

https://github.com/SWI-Prolog/bench

But this is just one of the public places are these programs can be found. The copyright of the plain Prolog benchmark programs should be assumed to belong to the original authors. Most of the programs lack any licensing information or distribution terms, however. Some don't even mention the author. Some go back to the earlier days of Prolog where programs were often shared in an academic setting without much concern about licensing. We redistribute these programs in good faith but understand that anyone repackaging the Logtalk distribution may choose to delete this example given the unclear legal status of some of these files.