Logtalk is an object-oriented logic programming language that extends and leverages the Prolog language with a feature set suitable for programming in the large. As a multi-paradigm language, it includes support for both prototypes and classes, protocols (interfaces), component-based programming through category-based composition, event-driven programming, coinduction, and high-level multi-threading programming. Logtalk uses standard Prolog syntax with the addition of some operators and directives and can be used with any Prolog implementation compliant with official and de facto standards as the back-end compiler.
The latest release of the Logtalk package is always available at the URL:
At this address you can also find additional documentation and information about Logtalk.
To register as a Logtalk user either use the registration form found at the Logtalk web site, http://logtalk.org/regform.html, or send an email message to:
with the following information:
email address, full name, organization, organization type (education, commercial, government, ...), prolog compilers used (optional), platforms (mac, pc, unix,...) (optional)
For support options, please consult the page http://logtalk.org/support.html.
Logtalk can be installed either from sources by running a few shell scripts
or by using one of the provided installers, depending on your operating
system. For manual installation, see the file INSTALL.md
for detailed
instructions.
See the user manual for a description of the source files organization
and for using instructions (to read the user manual open the file
manuals/index.html
with a web browser). Source files are formatted
using tabs (the recommended setting is a tab width equivalent to 4 spaces).
The file CUSTOMIZE.md
provides detailed instructions for customizing the
Logtalk installation and working environment.
The file QUICK_START.md
provides quick instructions for those of you in a hurry
to run Logtalk, provided that your favorite Prolog compiler is supported.
The reference and user manuals and the tutorial are provided in XHTML format and can be found in the "manuals" directory.
The file RELEASE_NOTES.md
contains descriptions of all Logtalk updates since the
first public version. Read it carefully if you have been using a previous
Logtalk version.
If you are upgrading from a previous Logtalk version, please check the file
UPGRADING.md
for instructions on how to upgrade your programs or your custom
adapter files to run under this new version.
If you want to cite Logtalk in your publications, please consult the file
BIBLIOGRAPHY.bib
for bibliographic references in BibTeX format.
Contributions, constructive criticism, patches, bug reports, and suggestions are always welcome. However, major code contributions to core files, such as the compiler, runtime, adapter files, library files, or tools can only be accepted with a transfer of copyright or if the submitted code is explicitly declared as public domain code. This simplifies the selling of commercial licenses, which provide a revenue source for the sustained development of Logtalk.
Logtalk is copyrighted by Paulo Moura. The Logtalk use and distribution
license can be found in the LICENSE.txt
file. Logtalk
follows the GNU General Public License 3, plus some additional terms as
per Section 7. The copyright notice and license applies to all files in
this release unless otherwise explicitly stated.
Some files that are part of the Logtalk distribution are distributed using a different license and/or are copyrighted by a Logtalk contributor.
Some of the included examples are adaptations to Logtalk of Prolog examples found elsewhere (e.g. in manuals, tutorials, books, and public mailing list discussions). The copyright in the examples original code should be assumed to belong to the original authors.
Logtalk is a registered trademark of Paulo Moura.