HYPROLOG, introduction

HYPROLOG is an extension to Prolog and Constraint Handling Rules (CHR) with abduction and assumptions. The system is basically implemented by a compiler that translates the HYPROLOG syntax in a rather direct way into Prolog and CHR; HYPROLOG queries are then executed directly by Prolog and CHR. It is currently available for SICStus Prolog 3 and 4 and for SWI Prolog; find information on downloading and conditions of use in the left menu.

HYPROLOG is fully integrated with the underlying Prolog+CHR environment, which means that all built-in and library predicates and constraint solvers can be used with abduction and assumptions. It allows any integrity constraint which can be written as a CHR rule. The only important limitation of HYPROLOG is its limited support of negation.

With respect to efficiency, the HYPROLOG system is among the fastest implementations of abduction due to the compiled approach, which thus employs also the underlying optimizing compilers for Prolog and CHR, and any future enhancements thereof. HYPROLOG's assumptions are about 10 times slower that the hardwired version available in BinProlog, but future improvements of CHR's indexing techniques may change this.

HYPROLOG has been thought out by Henning Christiansen and Veronica Dahl and implemented by Henning Christiansen.