The semantics of constraint logic programs

In this note we will investigate a form of logic programming with constraints. The constraints that we consider will not be restricted to statements on real numbers as in CLP(R), see . Instead our constraints will be arbitrary global constraints. The basic idea is that the applicability of a given rule is not predicated on the fact that individual variables satisfy certain constraints, but rather on the fact that the least model of the set rules that are ultimately applicable satisfy the constraint of the rule. Thus the role of clauses will be slightly different than in the usual Logic Programming with constraints. In fact, the paradigm we present is closely related to stable model semantics of general logic programming . We will define the notion of a constraint model of our constraint logic program and show that stable models of logic programs as well as the supported models of logic programs are just special cases of constraint models of constraint logic programs.

Springer eBooks, 1998

Real-world applications of theories for planning, scheduling, and design, call for more powerful and expressive theories than those provided by "classical" methods, which are based on a number of simplifying assumptions. Basic research on theories of constraint solving has made marked progress over the past few years. This paper sets out to show that the declarative nature of this new paradigm has significant advantages in software-engineering terms in the programming and maintenance phases. Moreover, the high efficiency of these methods allows the simulation of different strategies and supplies nearoptimal solutions within a short time. However, complex problems require the application of heuristics. Research results in this area are presented.

The Journal of Logic Programming, 1994

Constraint Logic Programming (CLP) is a merger of two declarative p a r adigms: constraint solving and logic programming. Though a relatively new eld, CLP has progressed in several quite di erent directions. In particular, the early fundamental concepts have been adapted to better serve i n di erent areas of applications. In this survey of CLP, a primary goal is to give a systematic description of the major trends in terms of common fundamental concepts. The three main parts cover the theory, implementation issues and programming for applications.

2005

This year marks the 40th anniversary of Alan Robinson's seminal paper on "A Machine-Oriented Logic Based on the Resolution Principle" that forms a basis for automated deduction and in particular logic programming, that started some three decades ago with the work of Robert Kowalski and Alain Colmerauer. The workshop on (constraint) logic programming is the annual meeting of the Society of Logic Programming (GLP e.V.) and brings together researchers interested in logic programming, constraint programming, and related areas like databases and artificial intelligence. Previous workshops have been held in Germany, Austria, and Switzerland. The technical program of the workshop included an invited talk, presentations of refereed and accepted papers and system descriptions, as well as non-refereed system demonstrations and poster presentations. The contributions in this volume were reviewed by at least two referees. We would like to thank all authors who submitted papers and all workshop participants for their fruitful discussions. We are grateful to the members of the program committee and of the local organisation as well as to the referees. We would like to express our thanks to the Society of Logic Programming (GLP e.V.) for handling finances and the University of Ulm for hosting the workshop.

2003

This book constitutes the thoroughly refereed post-proceedings of the Joint ERCIM/CologNet International Workshop on Constraint Solving and Constraint Logic Programming, held in Cork, Ireland in June 2002. The 14 revised full papers presented were carefully selected for inclusion in the book during two rounds of reviewing and revision. Among the topics addressed are verification and debugging of constraint logic programs, modeling and solving CSPs, explanation generation, inference and inconsistency ...

Proefschrift voorgedragen tot het behalen van het doctoraat in de informatica door Henk VANDECASTEELE mei 1999 c Katholieke Universiteit Leuven -Faculteit Toegepaste Wetenschappen Arenbergkasteel, B-3001 Heverlee, Belgium

Proceedings of the 20th ACM SIGPLAN-SIGACT symposium on Principles of programming languages - POPL '93, 1993

Central to constraint logic programming (CLP) languages is the notion of a global constraint solver which is queried to direct execution and to which constraints are monotonically added. We present a methodology for use in the compilation of CLP languages which is designed to reduce the overhead of the global constraint solver. This methodology is based on three optimizations. The first, refinement, involves adding new constraints, which in effect make information available earlier in the computation, guiding subsequent execution away from unprofitable choices. The second, removal, involves eliminating constraints from the solver when they are redundant. The last, reordering, involves moving constraint addition later and constraint remowd earlier in the computation. Determining the applicability of each optimization requires sophisticated global analysis. These analyses are based on abstract interpretation and provide information about potential and definite interaction between constraints.

1995

Abstract. Concurrent Constraint Programming (CCP) has been the subject of growing interest as the focus of a new paradigm for concurrent computation. Like logic programming it claims close relations to logic. In fact CCP languages are logics in a certain sense that we make precise in this paper.

2005

This year marks the 40th anniversary of Alan Robinson's seminal paper on "A Machine-Oriented Logic Based on the Resolution Principle" that forms a basis for automated deduction and in particular logic programming, that started some three decades ago with the work of Robert Kowalski and Alain Colmerauer. The workshop on (constraint) logic programming is the annual meeting of the Society of Logic Programming (GLP e.V.) and brings together researchers interested in logic programming, constraint programming, and related areas like databases and artificial intelligence. Previous workshops have been held in Germany, Austria, and Switzerland. The technical program of the workshop included an invited talk, presentations of refereed and accepted papers and system descriptions, as well as non-refereed system demonstrations and poster presentations. The contributions in this volume were reviewed by at least two referees. We would like to thank all authors who submitted papers and all workshop participants for their fruitful discussions. We are grateful to the members of the program committee and of the local organisation as well as to the referees. We would like to express our thanks to the Society of Logic Programming (GLP e.V.) for handling finances and the University of Ulm for hosting the workshop.