GNU PROLOG
                            ==========

INTRODUCTION

GNU Prolog is a native Prolog compiler with constraint solving over finite domains (FD) developed by Daniel Diaz (http://cri-dist.univ-paris1.fr/diaz/) Last information can be found at http://www.gnu.org/software/prolog or better at http://www.gprolog.org.

A lot of work has been devoted to the ISO compatibility. GNU Prolog is very close to the ISO standard.

Here are some features of GNU Prolog:

Prolog system:

• conforms to the ISO standard for Prolog (integer/floating arithmetic, streams, dynamic code, exceptions).
• clause indexing.
• a lot of extensions: global variables, definite clause grammars (DCG), sockets interface, operating system interface,...
• more than 300 Prolog built-in predicates.
• Prolog debugger and a low-level WAM debugger.
• line editing facility under the interactive interpreter with completion on atoms.
• powerful bidirectional interface between Prolog and C.

Compiler:

• native-code compiler producing stand alone executables.
• simple command-line compiler accepting a wide variety of files: Prolog files, C files, WAM files,...
• direct generation of assembly code 15 times faster than wamcc + gcc.
• most of unused built-in predicates are not linked (to reduce the size of the executables).
• compiled predicates (native-code) as fast as wamcc on average.
• consulted predicates (byte-code) 5 times faster than wamcc.

Constraint solver:

• FD variables well integrated into the Prolog environment (full compatibility with Prolog variables and
• integers). No need for explicit FD declarations.
• very efficient FD solver (comparable to commercial solvers).
• high-level constraints can be described in terms of simple primitives.
• a lot of predefined constraints: arithmetic constraints, boolean constraints, symbolic constraints, reified constraints,...
• several predefined enumeration heuristics.
• the user can define his own new constraints.
• more than 50 FD built-in constraints/predicates.

PORTS

GNU Prolog is currently ported to the following architectures:

• ix86 / GNU/Linux
• ix86 / Win32 using Cygwin (see file src/WINDOWS-OLD)
• ix86 / Win32 using MinGW (see file src/WINDOWS-OLD)
• ix86 / Win32 using MSVC++ (see file src/WINDOWS-OLD)
• ix86 / SCO
• ix86 / Solaris
• ix86 / FreeBSD
• ix86 / OpenBSD
• ix86 / NetBSD
• ix86 / Darwin (Mac OS X)
• x86_64 / GNU/Linux
• x86_64 / Solaris
• x86_64 / Win64 using MinGW64 (see file src/WINDOWS)
• x86_64 / Win64 using MSVC++ (see file src/WINDOWS)
• x86_64 / Darwin (Mac OS X)
• PowerPC / GNU/Linux
• PowerPC / Darwin (Mac OS X)
• PowerPC / NetBSD
• sparc / SunOS (4.1.3 or higher)
• sparc / Solaris
• sparc / NetBSD
• sparc64 / Solaris
• sparc64 / OpenBSD
• alpha / GNU/Linux
• alpha / OSF1
• mips / irix
• arm 32bits / GNU/Linux (armv6, armv7)
• arm 64bits (aarch64)/ GNU/Linux (armv8)
• arm 64bits (aarch64) / Darwin (Mac OS X) (armv8)
• RISC-V 64bits / GNU/Linux

INSTALLATION

Please refer to the INSTALL file (in the same directory)

USING GNU PROLOG

Be sure that adequate environment variables are set (see INSTALL)

You can then invoke the top-level using:

gprolog

and the compiler using:

gplc FILE

The simplest way to compile a Prolog file 'prog.pl' is then:

gplc prog.pl

which will produce the executable called prog (use gplc --help to have a brief overview of available options).

Refer to the documentation for more information (see below).

WINDOWS

In Microsoft Windows if you intend to use the gplc compiler as described in the documentation you need to ascertain the following conditions are met:

• for the port compiled with Microsoft Visual C++ (aka MSVC++) (tested with Microsoft Visual Studio 2019 Community) you'll need MinGW as.exe (renamed as mingw-as.exe) installed and the cl.exe compiler (used mainly as linker by GNU Prolog) available in your session path (alternatively link.exe is used).

• for the ports compiled either with MinGW, the gcc toolchain must be installed and available in your session path.

Observing these needs you'll also will be able to do the mixed language programming, as the examples included in the ExamplesC directory. However you'll need to write your own Makefile as the one provided is for gplc calling 'gcc' and the options passed by GNU Prolog will not work (see file ExamplesC/README).

DOCUMENTATION

The directory doc contains various versions of the manual. Refer to the file doc/README for more information.

An in-line HTML version can be accessed from the GNU Prolog web page.

WEB

The GNU Prolog web site is: http://www.gnu.org/software/prolog/ or also (primary web site): http://www.gprolog.org/

MAILING LIST

To communicate with other GNU Prolog users and/or implementors send a mail to users-prolog@gnu.org. To (un)subscribe to this mailing list send a mail to users-prolog-request@gnu.org with (un)subscribe in the subject line.

BUGS

Please report bugs to bug-prolog@gnu.org. To (un)subscribe to this mailing list send a mail to bug-prolog-request@gnu.org with (un)subscribe in the subject line.

COPYING

GNU Prolog is free software. Since version 1.4.0, GNU Prolog distributed under a dual license: LGPL or GPL. So, you can redistribute it and/or modify it under the terms of either:

• the GNU Lesser General Public License (LGPL) as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version.

or

• the GNU General Public License (GPL) as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

or both in parallel (as here).

GNU Prolog is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received copies of the GNU General Public License and the GNU Lesser General Public License along with this program. If not, see http://www.gnu.org/licenses/.

Remark: versions of GNU Prolog prior to 1.4.0 were entirely released under the GNU General Public License (GPL).