Report of the Workshop
The full-day workshop programme consisted of one invited talk, eight paper presentations and a discussion. Eighteen people were officially registered for the workshop. The effective number of participants was even higher and additional workshop proceedings were sold.
We were privileged to have a distinguished invited speaker: Martin Sulzmann (National University of Singapore) talking about his successful application of CHR in the functional programming world, systematic type system design for Haskell.
From the eleven papers submitted to the workshop, the Program Committee accepted eight papers for the paper presentations. These papers addressed various topics including type systems, Java implementations of CHR, lexicographic constraints, program analysis and optimization.
New to the CHR workshop this year was the Best Paper Award. The Program Committee selected the best paper from the accepted papers, based on its outstanding quality in both presentation and scientific contribution and for its impact on the field of CHR:
Jon Sneyers, Tom Schrijvers, Bart Demoen
The final discussion comprised future research plans and topics: CHR as business rules, analysis, implementation, the G12 project... Also a call for active participation was made in the CHR website and mailinglist. In particular, it was agreed to collect ideas for PhDs and other research topics on the CHR website.
We are grateful to all the participants, the authors of the submitted papers, the Program Committee members, and the referees for their time and efforts spent in the reviewing process, the ICLP 2005 organizers and the workshop chair Hai-Feng Guo.
Hope to see you all at CHR 2006 (time and location to be announced)!
Proceedings
The proceedings are available as a technical report.CHR 2005 Programme - October 5, 2005 - Room Llevant 2
| 09:00 - 09:15 | Workshop Opening |
| 09:15 - 10:15 |
Invited Talk by Martin Sulzmann Chameleon: Systematic Type System Design via Constraint Handling Rules |
| 10:15 - 10:45 |
Logical Rules for a Lexicographic Order Constraint Solver Thom Fruehwirth |
| 10:45 - 11:15 | Coffee Break |
| 11:15 - 11:45 |
Best Paper Ceremony and Presentation The Computational Power and Complexity of Constraint Handling Rules. Jon Sneyers, Tom Schrijvers, Bart Demoen |
| 11:45 - 12:15 |
A High Performance CHRv Execution Engine. Luis Menezes, Jairson Vitorino, Marcos Aurelio |
| 12:15 - 12:45 |
K.U.Leuven JCHR: a User-Friendly, Flexible and Efficient CHR System for Java. Peter Van Weert, Tom Schrijvers, Bart Demoen |
| 12:45 - 14:45 | Lunch Break |
| 14:45 - 15:15 |
A Type System for CHR. Emmanuel Coquery, Francois Fages |
| 15:15 - 15:45 |
Constraint Abduction and Constraint Handling Rules. Martin Sulzmann, Jeremy Wazny, Peter J. Stuckey |
| 15:45 - 16:15 |
Accurate Functional Dependency Analysis for Constraint Handling Rules. Gregory J. Duck, Tom Schrijvers |
| 16:15 - 16:45 | Coffee Break |
| 16:45 - 17:30 |
Reasoning about passive declarations in CHR Henning Christiansen |
| 17:30 - 18:00 | Discussion on the future trends in research and development of CHR |
Accepted Papers
- The Computational Power and Complexity of Constraint Handling Rules. Jon Sneyers, Tom Schrijvers, Bart Demoen
- Reasoning about passive declarations in CHR Henning Christiansen
- Accurate Functional Dependency Analysis for Constraint Handling Rules. Gregory J. Duck, Tom Schrijvers
- Constraint Abduction and Constraint Handling Rules. Martin Sulzmann, Jeremy Wazny, Peter J. Stuckey
- A Type System for CHR. Emmanuel Coquery, Francois Fages
- A High Performance CHRv Execution Engine. Luis Menezes, Jairson Vitorino, Marcos Aurelio
- Logical Rules for a Lexicographic Order Constraint Solver. Thom Fruehwirth
- K.U.Leuven JCHR: a User-Friendly, Flexible and Efficient CHR System for Java. Peter Van Weert, Tom Schrijvers, Bart Demoen
Invited Talk
Chameleon: Systematic Type System Design via Constraint Handling Rules, Martin Sulzmann.Type systems are important tools in the design, analysis, and verification of programming languages. Sophisticated applications often demand ad-hoc extensions to existing systems.
In this talk, I will give an overview of the main principles and ideas behind the Chameleon system. It integrates sophisticated reasoning capabilities into a programming language via its CHR programmable type system. Thus, we can program novel type system applications in terms of CHRs which previously required special-purpose systems. Furthermore, we can identify criteria in terms of CHRs under which we establish important properties such as decidability of type inference etc.
Important dates
- submission deadline: July 5, 2005
- notification of acceptance: July 21, 2005
- final version due: August 7, 2005
- workshop date: October 5, 2005
Introduction
The Constraint Handling Rules (CHR) language has become a major declarative specification and implementation language for constraint reasoning algorithms and applications. Algorithms are often specified using inference rules, rewrite rules, sequents, proof rules or logical axioms that can be directly written in CHR. Based on first order predicate logic, this clean semantics of CHR facilitates non-trivial program analysis and transformation. See the CHR website for more information.
The First Workshop on Constraint Handling Rules was organized in May 2004 in Ulm, Germany.
Topics of Interest
The workshop calls for full papers and short papers describing ongoing work, on all aspects of CHR, including topics such as:
- Semantics
- Implementations and Optimization
- Programming Environments (Debugging)
- Program Transformation and Generation
- Language Extensions (Types, Modules)
- Program Analysis
- Algorithms
- Constraint Solvers
- Retractable Constraints
- Logical Algorithms
- Programming Pearls
- Applications
- Critical Assessment
- Comparisons with Related Approaches
In addition, the workshop calls for CHR programming pearls. A programming pearl is a short piece of self-contained code of outstanding quality. Ideally it should be clearly correct, elegant, concise and efficient, though in some cases a (small) subset of these may not apply. It may be a useful application or may primarily be an example of a useful programming technique. Accompanying text explains the code and its qualities. These may be exposed by describing how a programmer could derive the code. Ideally, a CHR programming pearl should also showcase the CHR language, for example, declarative semantics, concurrency, on-line and any-time behavior.
Awards
The best paper receives the CHR Best Paper Award. It is chosen among all submissions for its outstanding quality in both presentation and scientific contribution and for its impact on the field of CHR.The best programming pearl submission receives the CHR Programming Pearl Award and will be presented at the workshop.
Submission Information
All papers must be written in English and not exceed 15 pages in Springer LNCS format. The authors are encouraged, although not obliged, to submit their papers already in Springer LNCS format. General information about the Springer LNCS series and the LNCS authors' instructions are available at the Springer LNCS/LNAI home page.
Submissions should be sent to chrworkshop@gmail.com and mention 'CHR 2005 Submission' in the subject. Every submission should include the names and e-mail addresses of the authors (with the corresponding author marked), the paper abstract in ASCII format and the actual paper in postscript or PDF format. The submission should also indicate whether it is a full paper, a short paper or a programming pearl.
Organization
Program Committee:
- Slim Abdennadher, German University in Cairo, Egypt
- Marco Alberti, Universita degli Studi di Ferrara, Italy
- Henning Christiansen, Roskilde University, Denmark
- Gregory Duck, Melbourne University, Australia
- Christian Holzbaur, University of Vienna, Austria
- Armin Wolf, Fraunhofer FIRST, Germany
Workshop Coordinators:
|
Tom Schrijvers (contact person)
|
Thom Frühwirth
|