July 2006 - Haskell - Haskell.org

rawSystem unpredictable with signals
by John Goerzen 09 Jul '06

09 Jul '06

Hi, I'm using System.Cmd.rawSystem in a program and have noticed a mysterious flaw: When I hit Ctrl-C while the child process is running, sometimes: 1) rawSystem returns ExitSuccess or 2) rawSystem raises an IOError saying the child terminated with a signal I am totally at a loss as to explain this difference in behavior. I would prefer it to choose option #2 always. However, even that is not quite ideal. It seems like it would be much better if ExitCode would be replaced with System.Posix.Process.ProcessStatus, which can indicate an Exited (with exit code), Terminated by signal, or Stopped by signal status. Getting an exception when the child was terminated by a signal, but not when it exits with a failure, seems inconsistent. I will probably write my own rawSystem replacement, that returns a ProcessStatus, and put it in MissingH.Cmd. -- John

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Strange type inference
by Emil Axelsson 07 Jul '06

07 Jul '06

Hello! I'm observing a strange type inference result in the program at the end of the message. term1 and term2 have the same definitions, except for a type annotation for term2, but GHCi infers the following types: *Main> :t term1 term1 :: Term () *Main> :t term2 term2 :: forall a. Term a Could anyone please explain this? Thank you, / Emil ----------------------------------- data Term a = X class Constructive term a | term -> a where construct :: term -> Term a instance Constructive (Term a) a where construct = id term1 = construct X term2 :: Term a term2 = construct X

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ANNOUNCE: Haskell XML Toolbox Version 6.1
by Uwe Schmidt 07 Jul '06

07 Jul '06

Haskell XML Toolbox 6.1 I would like to announce a new version of the Haskell XML Toolbox for processing XML. Functionality has not changed since HXT 6.0. HXT 6.1 works with the latest HTTP module (2006-07-07). Thanks to Bjorn Bringert <bringert(a)cs.chalmers.se> this one does not depend any more on the crypto package and contains only a single package http. So the installation process becomes simpler. There is no need to upgrade from a running HXT 6.0 version. More information and download: http://www.fh-wedel.de/~si/HXmlToolbox/index.html Please email comments, bugs, etc. to hxmltoolbox(a)fh-wedel.de Uwe -- University of Applied Sciences, Wedel, Germany http://www.fh-wedel.de/~si/index.html

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building c2hs on winows
by Anatoly Yakovenko 07 Jul '06

07 Jul '06

I can't get c2hs to build on windows with ghc-6.4.2 $ runhaskell.exe Setup.hs configure Setup.hs:11:57: Couldn't match `LocalBuildInfo' against `Distribution.PackageDescription.PackageDescription' Expected type: Args -> InstallFlags -> Distribution.PackageDescription.PackageDescription -> LocalBuildInfo -> IO ExitCode Inferred type: Args -> InstallFlags -> LocalBuildInfo -> IO ExitCode In the `postInst' field of a record In the record update: defaultUserHooks {postInst = addWrapperAndLib} Any ideas? Thanks, Anatoly

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IEEE/WIC/ACM IAT'06 - Deadline: 7/12/2006
by Jia Hu 06 Jul '06

06 Jul '06

[Apologies if you receive this more than once] Dear Colleague, In response to many requests for an extension, we are pleased to extend the paper submission deadline for IAT 2006 to ** July 12 **. Submission can be done online at: http://www.comp.hkbu.edu.hk/iwi06/iat/ We look forward to receiving your submissions soon. With best regards, Toyoaki Nishida PC chair of WI-IAT'06 ##################################################################### IEEE/WIC/ACM Intelligent Agent Technology 2006 CALL FOR PAPERS ##################################################################### 2006 IEEE/WIC/ACM International Conference on Intelligent Agent Technology (IAT'06) Hong Kong Convention and Exhibition Centre, Hong Kong, China, 18-22 December 2006. Sponsored By IEEE Computer Society Web Intelligence Consortium (WIC) Association for Computing Machinery (ACM) Co-Organized With Hong Kong Baptist University (HKBU) University/Corporate Sponsors Hong Kong Baptist University (HKBU) Microsoft Corp. http://www.comp.hkbu.edu.hk/iwi06/ (Papers Due: 12 July 2006) Accepted papers will be published in the conference proceedings by the IEEE Computer Society Press that are indexed by EI. ********************************************************************** The 2006 IEEE/WIC/ACM International Conference on Intelligent Agent Technology (IAT'06) will be jointly held with the 2006 IEEE/WIC/ACM International Conference on Web Intelligence (WI'06) and the 6th IEEE International Conference on Data Mining (ICDM'06) for providing synergism among the three research areas. It will provide opportunities for technical collaboration beyond that of previous conferences. The three conferences will have a joint opening, keynote, reception, and banquet. Attendees only need to register for one conference and can attend workshops, sessions and tutorials across the three conferences. We are also planning a joint panel and joint paper sessions that discuss common problems in the three areas. IAT 2006 provides a leading international forum to bring together researchers and practitioners from diverse fields, such as computer science, information technology, business, education, human factors, systems engineering, and robotics, to (1) examine the design principles and performance characteristics of various approaches in intelligent agent technology, and (2) increase the cross-fertilization of ideas on the development of autonomous agents and multi-agent systems among different domains. By encouraging idea-sharing and discussions on the underlying logical, cognitive, physical, and sociological foundations as well as the enabling technologies of intelligent agents, IAT 2006 will foster the development of novel paradigms and advanced solutions in agent-based computing. +++++++++++++++++++ Topics of Interest +++++++++++++++++++ The topics and areas include, but not limited to: * Autonomy-Oriented Computing (AOC) - Agent-Based Complex Systems Modeling and Development - Agent-Based Simulation - Autonomy-Oriented Modeling and Computation Methods - Behavioral Self-Organization - Complex Behavior Characterization and Engineering - Emergent Behavior - Hard Computational Problem Solving - Self-Organized Criticality - Self-Organized Intelligence - Swarm Intelligence - Nature-Inspired Paradigms * Autonomous Knowledge and Information Agents - Agent-Based Distributed Data Mining - Agent-Based Knowledge Discovery And Sharing - Autonomous Information Services - Distributed Knowledge Systems - Emergent Natural Law Discovery in Multi-Agent Systems - Evolution of Knowledge Networks - Human-Agent Interaction - Information Filtering Agents - Knowledge Aggregation - Knowledge Discovery - Ontology-Based Information Services * Agent Systems Modeling and Methodology - Agent Interaction Protocols - Cognitive Architectures - Cognitive Modeling of Agents - Emotional Modeling - Fault-Tolerance in Multi-Agent Systems - Formal Framework for Multi-Agent Systems - Information Exchanges in Multi-Agent Systems - Learning and Self-Adaptation in Multi-Agent Systems - Mobile Agent Languages and Protocols - Multi-Agent Autonomic Architectures - Multi-Agent Coordination Techniques - Multi-Agent Planning and Re-Planning - Peer-to-Peer Models for Multi-Agent Systems - Reinforcement Learning - Social Interactions in Multi-Agent Systems - Task-Based Agent Context - Task-Oriented Agents * Distributed Problem Solving - Agent-Based Grid Computing - Agent Networks in Distributed Problem Solving - Collective Group Behavior - Coordination and Cooperation - Distributed Intelligence - Dynamics of Agent Groups and Populations - Efficiency and Complexity Issues - Market-Based Computing - Problem-Solving in Dynamic Environments - Distributed Search * Autonomous Auctions and Negotiation - Agent-Based Marketplaces - Auction Markets - Combinatorial Auctions - Hybrid Negotiation - Integrative Negotiation - Mediating Agents - Pricing Agents - Thin Double Auctions * Applications - Agent-Based Assistants - Agent-Based Virtual Enterprise - Embodied Agents and Agent-Based Systems Applications - Interface Agents - Knowledge and Data Intensive Systems - Perceptive Animated Interfaces - Scalability - Social Simulation - Socially Situated Planning - Software and Pervasive Agents - Tools and Standards - Ubiquitous Systems and E-Technology Agents - Ubiquitous Software Services - Virtual Humans - XML-Based Agent Systems ++++++++++++++++++++++++++++++++++++ On-Line Submissions and Publication ++++++++++++++++++++++++++++++++++++ High-quality papers in all IAT related areas are solicited. Papers exploring new directions or areas will receive a careful and supportive review. All submitted papers will be reviewed on the basis of technical quality, relevance, significance, and clarity. Note that IAT'06 will accept ONLY on-line submissions, containing PDF versions. Paper submissions should be limited to a maximum of 8 pages in the IEEE 2-column format (see the IEEE Computer Society Press Proceedings Author Guidelines at http://www.computer.org/portal/pages/ieeecs/publications) and will be reviewed by the Program Committee on the basis of technical quality, relevance to data mining, originality, significance, and clarity. Please use the Submission Form on the IAT'06 website to submit your paper. Accepted papers will be published in the conference proceedings by the IEEE Computer Society Press that are indexed by EI. A selected number of IAT'06 accepted papers will be expanded and revised for inclusion in Web Intelligence and Agent Systems: An International Journal (http://wi-consortium.org/journal.html) and in Annual Review of Intelligent Informatics (http://www.wi-consortium.org/annual.html) The best paper awards will be conferred at the conference on the authors of (1) the best research paper and (2) the best application paper. Application-oriented submissions will be considered for the best application paper award. More detailed instructions and the On-Line Submission Form can be found from the IAT'06 homepage: http://www.comp.hkbu.edu.hk/~wii06/. ++++++++++++++++++++ Industry/Demo-Track ++++++++++++++++++++ We solicit Industry/Demo-Track papers by the following two methods: (1) Industry papers of 4 pages can be submitted on the same schedule as the research track. (2) Separate 2 page demo proposals can submitted at a later schedule. (3) Full regular paper submissions can include a demo option. That is, a full paper submissions will be asked to specify if they would like to give a demonstration; choice of demonstrations (while utilizing information from the regular reviewing process) will be selected based on value as a demonstration. For options (1) and (2), please find more detailed instructions at the homepages: http://www.comp.hkbu.edu.hk/iwi06/iat/?index=demo We are planning to arrange the Demo session in the afternoon of Dec 19 (before and during the conference reception), jointly with the WI'06 and ICDM'06 Demo sessions. +++++++++ Workshops +++++++++ As an important part of the conference, the workshop program will focus on new research challenges and initiatives. All papers accepted for workshops will be included in the Workshop Proceedings published by the IEEE Computer Society Press, and that are indexed by EI, and will be available at the workshops. Detailed information is available at the conference homepage. Note: we will not have a separate workshop registration fee this year (i.e., only one conference registration covers everything). I. Accepted as Fullday Workshops 1. International Workshop on Agent and Data Mining Interaction (ADMI) 2. International Workshop on Web Privacy Intelligence 3. International Workshop on Service Composition 4. The 3rd International Workshop on Web-based Support Systems (WSS'06) II. Accepted as Halfday Workshops 5. International Workshop on Intelligent Agents in Wireless Sensor Networks (IA-WSN) 6. International Workshop on Adaptation and Personalisation for e-Business Intelligence 7. International Workshop on Semantics in VO and WS 8. International Workshop on Communication between Human and Artificial Agents 9. International Workshop on Intelligent Web Interaction (IWI-2006) 10. International Workshop on P2P Computing and Autonomous Agents 11. International Workshop on GrC and Brain Informatics (BI) for WI 12. International Workshop on Multi-Agent Systems in E-Business: Concepts, Technologies and Applications (MASeB'06) 13. International Workshop on Research of Agent-based Government Horizon Business Integration Management Systems 14. International Workshop on Technologies and Applications of Knowledge Computing on the Web For more information, please visit the conference website at http://www.comp.hkbu.edu.hk/~wii06/. ++++++++++ Tutorials ++++++++++ IAT'06 also welcomes Tutorial proposals. IAT'06 will include tutorials providing in-depth background on subjects that are of broad interest to the intelligent agent community. Both short (2 hours) and long (half day) tutorials will be considered. The tutorials will be part of the main conference technical program. Detailed information is available at the conference homepage. Note: we will not have a separate tutorials registration fee this year (i.e., only one conference registration covers everything). ++++++++++++++++ Important Dates ++++++++++++++++ Workshop proposal submission: April 10, 2006 Electronic submission of full papers: ** July 12, 2006 ** Tutorial proposal submission: July 15, 2006 Notification of paper acceptance: September 4, 2006 Camera-ready copies of accepted papers: September 29, 2006 Workshops: December 18, 2006 Conference: December 19-22, 2006 ++++++++++++++++++++++++ Conference Organization ++++++++++++++++++++++++ Conference Chairs: * Jiming Liu, Hong Kong Baptist University, HK * Benjamin Wah, University of Illinois at Urbana-Champaign, USA Organizing Chair: * Yiu-Ming Cheung, Hong Kong Baptist University, HK Program Chair: * Toyoaki Nishida, Kyoto University, Japan Program Co-chairs: * Matthias Klusch, German Research Center for AI, Germany * Katia Sycara, Carnegie-Mellon University, USA * Makoto Yokoo, Kyushu University, Japan Industry/Demo-Track: * Wray Buntine, Helsinki Institute for Information Technology, Finland * Kazuhiro Kuwabara, ATR, Japan * Jianchang Mao, Yahoo! Inc., USA Workshop Co-Chairs: * Cory J. Butz, University of Regina, Canada * Ngoc Thanh Nguyen, Wroclaw University of Technology, Poland * Yasufumi Takama, Tokyo Metropolitan University, Japan Tutorial Co-Chairs: * Yuefeng Li, Queensland University of Technology, Australia * Pawan Lingras, Saint Mary's University, Canada * Hideaki Takeda, National Institute of Informatics/University of Tokyo, Japan Publicity Chairs: * Marcin Szczuka, Warsaw University, Poland * Guoyin Wang, Chongqing University of Posts and Telecommunications, China * Hui Xiong, Rutgers University, USA Sponsorship Chairs: * Man-chung Chan, Hong Kong Polytechnic University, HK * Einoshin Suzuki, Yokohama National University, Japan * Hongjin Yang, Chinese Academy of Sciences, China Program Vice Co-chairs: * Jeffrey Bradshaw, Institute for Human and Machine Cognition/UWF, USA * Barbara Dunin-Keplicz, Warsaw University, Poland * Amal El Fallah Seghrouchni, University of Paris 6 and CNRS, France * Maria Gini, University of Minnesota, USA * Churn-Jung Liau, Academia Sinica, Taiwan * Jeremy Pitt, Imperial College, UK * Eugenio Oliveira, University of Porto, Portugal * Liz Sonenberg, The University of Melbourne, Australia *** Contact Information *** Yiuming Cheung Hong Kong Baptist University, HK E-mail: ymc(a)Comp.HKBU.Edu.HK

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system command
by J. E. Palomar 05 Jul '06

05 Jul '06

Hi, I am newbie in Haskell programing and need to launch a shell command through a Haskell code. In other programing languages like C or Java I know how carry out this task; for instance the code system("ls -l ") in C or exec("ls -l") in Java work fine and lists the working directory. I know that in interactive mode the Haskell command :! ls -l is similar, but ¿It is possible something like in Haskell non-interactive mode? Thaks in advance. Helptex23

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ICFP contest registration open!
by Big Chris 04 Jul '06

04 Jul '06

Hi all, Registration for the 2006 ICFP contest is now open. As you're probably aware, teams using haskell have won for the last two years. I'm one of the organizers, and as a haskell hacker myself, I'd love to see us win it again :). I can promise you that this year's competition is going to be more fun than any previous year. Our theme is "Computational archaeolinguistics." You can find more info at www.icfpcontest.org. What follows is our standard announcement. I hope many of you will participate! --Chris Casinghino --------------------------------- Language lovers: Registration is now open for the 9th Annual ICFP Programming Contest! http://icfpcontest.org/ The contest, associated with the International Conference on Functional Programming, will be held on the weekend of July 21-24. The contest task will be released at noon EDT on Friday, and entries will be accepted until noon EDT on Monday. Registration is free and open to all. Teams may participate from any location, and may use any programming language(s). Last year, 360 participants formed 161 teams from 26 countries. Prize money totaling $1750 US will be awarded to help defray the costs of travel to the conference for the winners and for small cash prizes. In addition, the winners of the contest will receive bragging rights for the programming language of their choice. This makes the contest a popular avenue for demonstrating the superiority of a favorite language, or for exercising an experimental tool. Though the specifics are secret until the contest begins, we promise that this year's task will be very different from past competitions. The theme is "computational archaeolinguistics." Stay tuned for more information as the contest approaches! - 2006 Contest Organizers CMU Principles of Programming Group

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Re: [Haskell] GADTs are not nice to me ;-)
by Wolfgang Jeltsch 04 Jul '06

04 Jul '06

Am Montag, 3. Juli 2006 18:46 schrieb Simon Peyton-Jones: > Thanks. Can you confirm that it's fixed in 6.4.2? And if so, can you > record that too? No point in us haring after fixed bugs! > > S As Chris Kuklewicz pointed out, this bug doesn't seem to be completely fixed in 6.4.2. Currently, I neither can confirm this nor can I disprove it since at the moment there seem to be no Debian packages for 6.4.2 which I could install and I don't have the time to install GHC from source. Best wishes, Wolfgang

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problem building syb-generics
by Matthew Pocock 04 Jul '06

04 Jul '06

Hi, I had some trouble getting syb-generics 2.9 to compile with ghc 6.5 (don't ask - I should probably be waiting for a stable release). I fixed the first problem by replacing a definition with in-line type info by splitting the type out, although I am not sure that I have done it right. Can anybody shed some light on this? Matthew ---------the error-------- Building syb-generics-2.9... [1 of 7] Compiling Data.Context ( Data/Context.hs, dist/build/Data/Context.o ) Data/Context.hs:48:9: A pattern type signature cannot bind scoped type variables `l' unless the pattern has a rigid type context In the pattern: l :: l () In the definition of `pairCtx': pairCtx (l :: l ()) (r :: r ()) = undefined :: PairCtx l r () --------original code------ pairCtx (l::l ()) (r::r ()) = undefined::PairCtx l r () --------my code------------- pairCtx :: l () -> r () -> PairCtx l r () pairCtx l r = undefined

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Haskell I/O inside: down the rabbit's hole
by Bulat Ziganshin 04 Jul '06

04 Jul '06

Hello haskell, Haskell I/O has always been a source of confusion and surprises for new Haskellers. While simple I/O code in Haskell looks very similar to its equivalents in imperative languages, attempts to write somewhat more complex code often end with a total mess. This is because Haskell I/O is really very different internally. I'm glad to present our collective work, the tutorial: HASKELL I/O INSIDE: DOWN THE RABBIT'S HOLE http://haskell.org/haskellwiki/IO_inside This tutorial is directed toward exhaustive explanation of IO monad arrangement and details of it's practical usage for building complex programs. The tutorial is still growing. Feel free to add your own material or tell us about questions you want to be answered there. I hope that this text will address the critical need of comprehensive Haskell I/O manual and will be especially useful for new Haskell programmers oriented to develop real-world programs. -- Best regards, Bulat mailto:Bulat.Ziganshin@gmail.com

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