Institute of Software Engineering and Programming Languages

CHR Research Group

Constraint Handling Rules (CHR) is a concurrent committed-choice constraint logic programming language consisting of guarded rules that transform multi-sets of atomic formulas (constraints) until exhaustion. It was designed by Thom Fruehwirth in 1991. CHR can embed many rule-based formalisms and systems, and it can describe algorithms in a compact declarative way without compromising efficiency. The clean semantics of CHR ensures that several desirable properties hold for CHR programs and also facilitates sophisticated program analysis. CHR libraries exist for Prolog, Haskell, Java, Javascript, Python and C. CHR is also available online for experimentation with many example programs. More than 250 academic and industrial projects worldwide use CHR, and about 2500 research papers reference it.

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2012

50.
Zaki, Amira; Frühwirth, Thom; Geller, Ilvar
Parallel Execution of <prt>C</prt>onstraint <prt>H</prt>andling <prt>R</prt>ules on a <prt>G</prt>raphical <prt>P</prt>rocessing <prt>U</prt>nit
CHR '12: Proc. 9th Workshop on Constraint Handling Rules, Page 82-90
September 2012
49.
Sneyers, Jon; Frühwirth, Thom
Proceedings of the 9th International Workshop on Constraint Handling Rules (CHR 2012)
Volume Report CW 624
Leuven, Belgium
Department of Computer Science, Katholieke Universiteit Leuven
September 2012
48.
Bolock, Alia El; Zaki, Amira; Frühwirth, Thom
Substitution-based CHR Solver for Bivariate Binomial Equation Sets
CHR 2012: Ninth International Workshop on Constraint Handling Rules
September 2012
47.
Wielemaker, Jan; Frühwirth, Thom; Koninck, Leslie De; Triska, Markus; Uneson, Marcus
SWI Prolog Reference Manual 6.2.2
September 2012
Publisher: Books On Demand
ISBN:978-3-84-822617-7
46.
Triossi, Andrea; Orlando, Salvatore; Raffaetà, Alessandra; Frühwirth, Thom
Compiling CHR to Parallel Hardware
Proceedings of the 14th Symposium on Principles and Practice of Declarative ProgrammingfromPPDP '12, Page 173--184
Publisher: ACM, New York, NY, USA
2012
DOI:10.1145/2370776.2370798
ISBN:978-1-4503-1522-7

2011

45.
Langbein, Johannes; Stelzer, Roland; Frühwirth, Thom
A Rule-Based Approach to Long-Term Routing for Autonomous Sailboats
In Schlaefer, A. and Blaurock, O., Editor, Robotic Sailing: Proceedings of the 4th International Robotic Sailing Conference, Page 195-204
In Schlaefer, A. and Blaurock, O., Editor
Publisher: Springer-Verlag
2011
DOI:10.1007/978-3-642-22836-0_14
44.
Raiser, Frank; Frühwirth, Thom
Analysing graph transformation systems through constraint handling rules
Theory and Practice of Logic Programming, 11 (1) :65-109
January 2011
DOI:10.1017/S1471068410000438

2010

43.
Betz, Hariolf; Raiser, Frank; Frühwirth, Thom
A Complete and Terminating Execution Model for Constraint Handling Rules
Theory and Practice of Logic Programming, 10 (4-6) :597-610
July 2010
DOI:10.1017/S147106841000030X
42.
Langbein, Johannes; Raiser, Frank; Frühwirth, Thom
A State Equivalence and Confluence Checker for CHR
In Van Weert, P. and De Koninck, L., Editor, Proceedings of the 7th International Workshop on Constraint Handling RulesfromReport, Page 1-7
In Van Weert, P. and De Koninck, L., Editor
Publisher: Departement of Computer Science, Katholieke Universiteit Leuven
May 2010
41.
Geiselhart, Florian; Raiser, Frank; Sneyers, Jon; Frühwirth, Thom
MTSeq: Multi-touch-enabled CHR-based Music Generation and Manipulation
In Van Weert, P. and De Koninck, L., Editor, Proceedings of the 7th International Workshop on Constraint Handling RulesfromReport, Page 41-46
In Van Weert, P. and De Koninck, L., Editor
Publisher: Departement of Computer Science, Katholieke Universiteit Leuven
May 2010