A Category-Based Equational Logic Semantics to Constraint Programming

This paper exploits the point of view of constraint programming as computation in a logical system, namely constraint logic. We dene the basic ingredients of constraint logic, such as constraint models and generalised polynomials. We show that constraint logic is an institution , and we internalise the study of constraint logic to the framework of category-based equational logic. By showing that constraint logic is a special case of category-based equational logic, we integrate the constraint logic programming paradigm into equational logic programming. Results include a Herbrand theorem for constraint logic programming characterising Herbrand models as initial models in constraint logic.