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This file is part of Logtalk https://logtalk.org/ SPDX-FileCopyrightText: 1998-2024 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.

QUICK START INSTRUCTIONS

Starting up Logtalk

Install Logtalk by using either the installer provided for your operating-system or by following the manual installation instructions in the INSTALL.md file.

On POSIX operating-systems, the following shell scripts are installed by default for running Logtalk with the supported backend Prolog compilers (which must be installed and up-to-date before running these scripts):

• B-Prolog: bplgt (experimental)
• Ciao Prolog: ciaolgt (experimental; first run may require sudo)
• CxProlog: cxlgt
• ECLiPSe: eclipselgt
• GNU Prolog: gplgt
• JIProlog: jiplgt (first run may require sudo)
• LVM: lvmlgt
• Quintus Prolog: quintuslgt (experimental)
• SICStus Prolog: sicstuslgt
• SWI-Prolog: swilgt
• Tau Prolog: taulgt
• Trealla Prolog: tplgt
• XSB: xsblgt (first run may require sudo)
• YAP: yaplgt Man pages for all scripts are also provided on POSIX systems. HTML versions of the man pages are available in the Logtalk website.

  On macOS systems, `/opt/local/bin` must be in your PATH to run the scripts when using the provided installer. Terminal command files for running Logtalk with selected backend Prolog compilers are also available on the Logtalk installation folder (by default, `/opt/local/share/logtalk/scripts/macos/command_files`). For easy access, the installer creates an alias to the Logtalk folder in the Applications folder.

  On Windows systems, shortcuts for running Logtalk with selected backend Prolog compilers are created on the `Start Menu/Programs/Logtalk menu. The first run of the JIProlog and XSB integration shortcuts may require administrator privileges depending on the JIProlog and XSB installation (right-click on the shortcut and select the "Run as administrator" option). PowerShell versions of the scripts listed above are also available (e.g. gplgt.ps1`). PowerShell 7.3 or later version is required for running these scripts.

  If you get an unexpected failure when using one of the Prolog integration scripts or shortcuts, consult the adapters/NOTES.md file in the Logtalk installation folder for compatibility notes. For the integration scripts, see also the integration script man page.

  For a quick overview of some of the main Logtalk concepts, see the at Learn X in Y minutes Where X=Logtalk tutorial. See also the bundled Handbook by opening the manuals/index.html file with a web browser. The Installing Logtalk and Writing and running applications sections in the User Manual will provide you with a basic understanding of how to start Logtalk as well as how to compile and load Logtalk code.

Basic help on Logtalk usage at the top-level interpreter

Start Logtalk and call the goal {help(loader)} followed by help::help. This will provide you with an overview on how to get help and how to load and debug your code.

Help on understanding compiler errors and warnings

Start Logtalk and call the goal {tutor(loader)}. The tutor tool will augment compiler errors and warnings with explanations and suggestions on how to solve the reported problems.

Loading libraries, examples, and tools

From within a source file, use the goal `logtalk_load(<name>(loader))`. For example, logtalk_load(optionals(loader)). At the top-level interpreter, a `{<name>(loader)} shortcut is available. For example, {debugger(loader)}`.

Running an example

You may now try some examples. The examples/NOTES.md file contains a brief description of each example. The learning guide includes a suggested walkthrough.

1. Select and open one of the examples directory.
2. Read the example NOTES.md file for a description of the example.
3. Open the SCRIPT.txt file for instructions on how to load the example and for sample queries that you may try by copying-and-pasting them to your Prolog interpreter top-level.

Writing your own programs

Ready to start writing your own programs?

1. Read the Handbook sections on "Writing and running applications" and "Debugging". If you want to use your Prolog backend resources, read also the section on "Prolog integration and migration".
2. Take a look at the [coding](coding) directory. There you will find syntax support files for popular text editors which enable syntax coloring and other text services when editing Logtalk source files. There's also support for syntax highlighters used for publishing source code and for source code versioning systems.
3. The [tools](tools) directory contains a comprehensive set of developer tools to help you test, debug, analyze, and document your applications.
4. Create a directory (preferably outside of your Logtalk user folder, which is updated when you update Logtalk) with a suitable name to hold all the files of your application.
5. Copy or rename the [settings-sample.lgt](settings-sample.lgt) file to settings.lgt, and modify it to preload developer tools (e.g. the help and debugger tools), to define library aliases for your applications, to define default compiler flags, and more (see the comments in the file itself and the CUSTOMIZE.md file for details).
6. Copy to your application directory the [loader-sample.lgt](loader-sample.lgt) file, rename it to loader.lgt, and modify it to load your application source files. You may also copy the [tester-sample.lgt](tester-sample.lgt) and [tests-sample.lgt](tests-sample.lgt) files, renaming them to tester.lgt and tests.lgt, and editing them to define and run your application unit tests.
7. Have fun!