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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2015

65.
Gall, Daniel; Frühwirth, Thom
A Refined Operational Semantics for ACT-R
ACM 17th International Symposium on Principles and Practice of Declarative Programming (PPDP 2015), Siena, Italy
July 2015
DOI:10.1145/2790449.2790517
64.
Sharaf, Nada; Abdennadher, Slim; Frühwirth, Thom
DiagrammaticCHR: A Diagrammatic Representation of CHR Program
19th International Conference Information Visualisation (iV2015)
Publisher: IEEE Digital Library
July 2015
DOI:10.1109/iV.2015.31
63.
Dahl, Veronica; Tessaris, Sergio; Frühwirth, Thom
Imperfect Querying through Womb Grammars plus Ontologies
Workshop Ontologies and Logic Programming for Query Answering (ONTOLP'15) at IJCAI-2015, Buenos Aires
July 2015
DOI:10.1109/iV.2015.31
62.
Gall, Daniel; Frühwirth, Thom
An Adaptable Implementation of ACT-R with Refraction in Constraint Handling Rules
13th International Conference on Cognitive Modeling (ICCM), Groningen
April 2015

2014

61.
Sharaf, Nada; Abdennadher, Slim; Frühwirth, Thom
A Visualization Tool for Constraint Handling Rules
24th International Symposium on Logic-Based Program Synthesis and Transformation (LOPSTR 2014), Canterbury, UK
September 2014
60.
Saad, Aya; Frühwirth, Thom; Gervet, Carmen
The P-Box CDF-Intervals: A Reliable Constraint Reasoning with Quantifiable Information
, Selected Papers of the 30th International Conference on Logic Programming (ICLP 2014)Volume14(4-5), Page 461-475
Publisher: Cambridge University Press
July 2014
DOI:10.1017/S1471068414000143
59.
Gall, Daniel; Frühwirth, Thom
Exchanging Conflict Resolution in an Adaptable Implementation of ACT-R
, Selected Papers of the 30th International Conference on Logic Programming (ICLP 2014)Volume14(4-5), Page 525-538
Publisher: Cambridge University Press
July 2014
58.
Nogatz, Falco; Frühwirth, Thom
From XML Schema to JSON Schema: Translation with CHR
11th Workshop on Constraint Handling Rules (CHR 2014), Vienna
July 2014
57.
Wielemaker, Jan; Frühwirth, Thom; Koninck, Leslie De; Triska, Markus; Uneson, Marcus
SWI Prolog Reference Manual 7.1
May 2014
Publisher: BOD
ISBN:9783735738035

2013

56.
Sneyers, Jon; Schreye, Daniel De; Frühwirth, Thom
Probabilistic Legal Reasoning in CHRiSM
, Selected Papers of the 29th International Conference on Logic Programming (ICLP 2013)Volume13, 4-5-Online-Supplement
Publisher: Cambridge University Press
August 2013