gprolog

GNU Prolog is a free Prolog compiler

GNU Prolog is a native Prolog compiler with constraint solving over finite domains (FD) developed by Daniel Diaz (<a href="http://loco.inria.fr/~diaz">http://loco.inria.fr/~diaz</a> ). GNU Prolog is a very efficient native compiler producing (small) stand-alone executables. GNU-Prolog also offers a classical top-level+debugger. GNU Prolog conforms to the ISO standard for Prolog but also includes a lot of extensions (global variables, DCG, sockets, OS interface,...). GNU Prolog also includes a powerful constraint solver over finite domains with many predefined constraints+heuristics.