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Invitation to write book reviews
by S.J.Thompson 30 Jul '04

30 Jul '04

The journal of functional programming publishes reviews of books on functional programming an related subjects. A list of currently available titles is always at http://www.cs.kent.ac.uk/people/staff/sjt/JFP/available.html and currently it lists Inductive Synthesis of Functional Programs Ute Schmid Verification of Reactive Systems: Formal Methods and Algorithms Klaus Schneider Duration Calculus: A Formal Approach to Real-Time Systems Zhou Chaochen, Michael R. Hansen Concepts, Techniques and Models of Computer Programming Peter van Roy and Seif Haridi Programming Languages and Operational Semantics Maribel Fernandez The Haskell Road to Logic, Maths and Programming Kees Doets and Jan van Eijck If you are interested in reviewing any of these titles, or if you would like to suggest any other books for review, please mail me. If you are interested, but not sure what writing a review involves, there are review guidelines at http://uk.cambridge.org/journals/functionalprogramming/reviews.htm Regards Simon Thompson

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ANNOUNCE: Chameleon version (04-07)
by Martin Sulzmann 30 Jul '04

30 Jul '04

We are pleased to announce Chameleon version 04-07. Latest version can be downloaded via http://www.comp.nus.edu.sg/~sulzmann/chameleon/ New features include: * Improved Type Inference and Lexically Scoped Annotations * Improving Type Error Diagnosis * Beyond Functional Dependencies. * Existentially Quantified Type Classes. (includes guarded recursive data types aka first-class phantom types etc) Martin Sulzmann (sulzmann at comp.nus.edu.sg) Jeremy Wazny (jeremyrw at students.cs.mu.OZ.AU)

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IFL'04, Luebeck: Hotel reservation deadline approaching
by Clemens Grelck 29 Jul '04

29 Jul '04

Please accept our apologies if you receive multiple copies of this mail. Sincerely, Clemens Grelck and Frank Huch IFL'04 ------------------------------------------------------------------------ Announcement, Call for Papers and Call for Participation for the 16th International Workshop on Implementation and Application of Functional Languages (IFL'04) September 8th -- 10th, 2004, Luebeck, Germany http://www.isp.uni-luebeck.de/ifl04/index.htm ------------------------------------------------------------------------ Important Dates --------------- Jul 15th, 2004 Hotel reservation deadline =========================================== Jul 31st, 2004 Registration deadline Aug 20th, 2004 Submission deadline for draft proceedings Sep 8th, 2004 Workshop starts in the morning Sep 9th, 2004 Excursion and banquet dinner Sep 10th, 2004 Workshop ends in the evening Sep 11th, 2004 Post-workshop excursion Oct 29th, 2004 Submission deadline for post-refereeing process Dec 10th, 2004 Notification of acceptance/rejection Jan 21st, 2005 Camera-ready papers due Scope and Topics ---------------- The IFL workshops form a tradition that has lasted for over a decade. The aim of these workshops is to bring together researchers actively engaged in the implementation and application of functional and function-based programming languages. They provide an open forum for researchers who wish to present and discuss new ideas and concepts, work in progress, preliminary results, etc. related primarily but not exclusively to the implementation and application of functional languages. Topics of interest include, but are not limited to - language concepts - type checking - compilation techniques - (abstract) interpretation - automatic program generation - (abstract) machine architectures - formal aspects - array processing - concurrent/parallel programming - concurrent/parallel program execution - heap management - runtime profiling - performance measurements - debugging and tracing - verification - tools and programming techniques Papers on applications demonstrating the suitability of novel ideas in any of the above areas and contributions on related theoretical work are also welcome. The change of the workshop name adding the term "application" is to reflect the broader scope IFL has gained over recent years. Contributions ------------- Prospective authors are encouraged to submit papers to be published in the draft proceedings (published as a technical report of the Institute of Computer Science and Applied Mathematics of the University of Kiel) and to give presentations at the workshop. All contributions must be written in English, conform to the Springer-Verlag LNCS series format (see: http://www.springer.de/comp/authors/index.html) and not exceed 16 pages. Papers must be submitted by August 20th as postscript or pdf files through the workshop web page at http://www.isp.uni-luebeck.de/ifl04/index.htm. Following the IFL tradition since 1996, a subset of high-quality contributions will be published by Springer-Verlag in the well-known Lecture Notes in Computer Science (LNCS) series. All participants who gave a presentation at the workshop are invited to submit a revised version of their paper for the post-workshop proceedings. They will be refereed by the program committee according to normal conference standards. Program Committee ----------------- Matthias Blume (Toyota Technological Institute, Chicago, USA) Andrew Butterfield (Trinity College Dublin, Ireland) Manuel Chakravarty (University of New South Wales,Sydney,Australia) Clemens Grelck (chair)(University of Luebeck, Germany) Frank Huch (chair) (University of Kiel, Germany) Hans-Wolfgang Loidl (Ludwig-Maximilians-University, Munich, Germany) Frederique Loulergue (University of Paris XII, France) Simon Marlow (Microsoft Research, Cambridge, UK) Greg Michaelson (Heriot-Watt University, Edinburgh, UK) Yolanda Ortega-Mallen (University Complutense of Madrid, Spain) Rinus Plasmeijer (University of Nijmegen, The Netherlands) Colin Runciman (University of York, UK) Peter Thiemann (University of Freiburg, Germany) Phil Trinder (Heriot-Watt University, Edinburgh, UK) German Vidal (Technical University of Valencia, Spain) Workshop Organization --------------------- Clemens Grelck Frank Huch Institute of Software Technology Institute of Computer Science and Programming Languages and Applied Mathematics University of Luebeck, Germany University of Kiel, Germany Further Information ------------------- Website: http://www.isp.uni-luebeck.de/ifl04/index.htm E-mail: ifl04(a)isp.uni-luebeck.de

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confusing language in report and a bug in (ghc|hugs)
by John Meacham 29 Jul '04

29 Jul '04

in section 3.17.2 case #6 of the haskell report There is some confusing language in the report. Furthermore there is either a bug in ghc, or hugs, depending on which way you interpret it. it says: # Matching against a constructor using labeled fields is the same as # matching ordinary constructor patterns except that the fields are # matched in the order they are named in the field list. All fields # listed must be declared by the constructor; fields may not be named # more than once. Fields not named by the pattern are ignored (matched # against _). If you interpret 'field list' to mean the order the fields appear in the pattern then given the code below "bar" should be printed, as the 'b' field is compared and fails so the a field is never matched against. If you interpret 'field list' to mean the order the fields were DECLARED in, then this should equal _|_ as the 'a' field is matched first and is undefined. ghc seems to follow the second interpretation, hugs the first. If the first is indeed the correct interpretation, (it is what I thought) I don't see a trivial translation to dispose of fields, as there is no easy way in Haskell98 to change the order of pattern matching without rewriting everything as a big mess of nested cases. (i mean, obviously it can be done, but the translation is harder than just placing the patterns in the right slots and dropping the field names) -- the code -- data Foo = Foo { a,b::Int } au = Foo { a = undefined, b = 0 } main = case au of Foo { b = 1, a = 0 } -> print "foo" _ -> print "bar" ghc => error: Prelue.undefined hugs => "bar" -- John Meacham - ⑆repetae.net⑆john⑈

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ICFP'04 Call for Participation
by Amr A Sabry 28 Jul '04

28 Jul '04

The 2004 International Conference on Functional Programming (ICFP) Snowbird, Utah September 19-22, 2004 Call for Participation ***************************************************** *** Early registration rates until 25 August 2004 *** ***************************************************** Registration, hotel information, conference program (accepted papers, poster session, and affiliated workshops on Erlang, Haskell, and Scheme) at the following web site: http://www.cs.indiana.edu/icfp04/

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Re: [Haskell] Memo function help
by MR K P SCHUPKE 28 Jul '04

28 Jul '04

>Note that it doesn't have to be lazy, Most traditional dynamic programming techniques use arrays to store intermediate values. Lazy techniques could use a prohibative amount of memory due to the size of the thunks. The best general technique I have found in Haskell is to use unboxed mutable arrays in the ST monad to compute the result eagerly. Even this can result in huge memory usage. The best lazy technique I have seen is this: http://www.csse.monash.edu.au/~lloyd/tildeStrings/Alignment/92.IPL.html (in tests this lazy method was more or less the same speed as the eager method, but it does take advantage of particular access patterns in the string edit distance algorithm). Keean.

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Memo function help
by Tom Hofte 28 Jul '04

28 Jul '04

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Announce: wxHaskell 0.8
by Daan Leijen 27 Jul '04

27 Jul '04

Announcement: wxHaskell version 0.8 ---------------------------------------------------------------------- <http://wxhaskell.sourceforge.net> I am pleased to announce a new release of wxHaskell. The library is now 1 year old, and more than 4000 downloads further. This new release has support for the powerful wxGrid control, managed resources, and system colors. Futhermore, all object references are now checked, raising a Haskell exception if they are not valid. The MacOS X version is much more stable now than the previous release. Binary installers are provided for MacOS X, Linux (RPM), and Windows. The webpage has a screenshot of a heap profile viewer for GHC written in wxHaskell by Wei Tan. There is also a *draft* version of an article about the design of wxHaskell. I have to submit a final version this Friday and any comments are very welcome. All the best, Daan Leijen. ---------------------------------------------------------------------- wxHaskell is a portable GUI library for Haskell. The goal of the project is to provide an industrial strength portable GUI library, but without the burden of developing (and maintaining) one ourselves. wxHaskell is therefore build on top of wxWidgets -- a comprehensive C++ library that is portable across all major GUI platforms; including GTK, Windows, X11, and MacOS X. Furthermore, it is a mature library (in development since 1992) that supports a wide range of widgets with native look-and-feel, and it has a very active community (ranked among the top 25 most active projects on sourceforge). Since most of the interface is automatically generated from the wxEiffel binding, the current release of wxHaskell already supports about 75% of the wxWindows functionality -- about 2900 methods in 500 classes with 1400 constant definitions. wxHaskell has been build with GHC 6.x on Windows, MacOS X and Unix systems with GTK. A binary distribution is available for Windows, Linux (RPM) and MacOS X. And even if you don't intend to write GUI's yourself, it will be fun to check out the screenshots at <http://wxhaskell.sourceforge.net>. ---------------------------------------------------------------------- Version 0.8 ----------- Non backward compatible changes: - Added wildcards argument to the "fileSaveDialog" function. - Removed the call to "buttonSetDefault" in the "defaultButton" property since GTK seems to enlarge the button in that case. - Removed alignment argument for text controls - Removed sorted and labels argument for choice and combo boxes. - Removed sorted argument for listboxes. - Added default "stretch" to every toplevel layout, assuring that such layout gets at least all available space assigned. - (un)set "maximize box" when "resizeable" is set. - Removed default "wxTAB_TRAVERSAL" style on frames (to make the grid work correctly). - Renamed "WXCore.WxcClassTypes" to "WXCore.WxcClassInfo". Backward compatible additions: - Added pure "bitmap" and "sound" - Added "variable" objects (mutable variables) - Added custom control demo. - Made "refresh" erase the background too. - Added "children" attribute for windows. - Added "border" attribute for windows. - Added "tabTraversal" attribute for windows. - Added wxGrid events and demo (samples/wx/Grid.hs). - Improved signatures for wxGrid. - Added "changes.txt" file :-) - Added "HAS_RADIO_MENU_ITEMS" to "isDefined". - Added support for radio menu items. - New wxHaskell+HOpenGL sample added to the contributions. Thanks to Shelarcy and Sean Seefried. - Added "Align" and "Wrapped" classes to set alignment and wrap mode for text controls. - Added "Sorted" class to set the sort mode of choice, combo box, and listbox controls. - Added "creation time" attributes that use reflective attributes not compositional (and thus not so nice), but very convenient! - Added "entry" as shorthand for "textEntry" - Added "SystemColor" and "colorSystem" to get standard system colors. - Defaulted background color of "Frame"s to Color3DFace (as a Panel). - Made the definition of "Closure" in "wrappers.h" more liberal to support wxOCaml better. - Added "frameCentre" method - Huge internal changes: split up wxcClasses in three files and added support for managed objects like bitmaps. Also added checks for NULL pointers. Bug fixes: - HtmlLinkClicked events are now properly generated. - Fixed bug that crashed wxHaskell when a tree control had the focus and a key was pressed. Thanks to Olivier Spier for sending a fix. - The "item" attribute of a list control always returned the first item and disregarded the parameter. Thanks to Olivier Spier for sending a fix.

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Announce: wxHaskell 0.8
by Daan Leijen 27 Jul '04

27 Jul '04

Announcement: wxHaskell version 0.8 ---------------------------------------------------------------------- <http://wxhaskell.sourceforge.net> I am pleased to announce a new release of wxHaskell. The library is now 1 year old, and more than 4000 downloads further. This new release has support for the powerful wxGrid control, managed resources, and system colors. Futhermore, all object references are now checked, raising a Haskell exception if they are not valid. The MacOS X version is much more stable now than the previous release. Binary installers are provided for MacOS X, Linux (RPM), and Windows. The webpage has a screenshot of a heap profile viewer for GHC written in wxHaskell by Wei Tan. There is also a *draft* version of an article about the design of wxHaskell. I have to submit a final version this Friday and any comments are very welcome. All the best, Daan Leijen. ---------------------------------------------------------------------- wxHaskell is a portable GUI library for Haskell. The goal of the project is to provide an industrial strength portable GUI library, but without the burden of developing (and maintaining) one ourselves. wxHaskell is therefore build on top of wxWidgets -- a comprehensive C++ library that is portable across all major GUI platforms; including GTK, Windows, X11, and MacOS X. Furthermore, it is a mature library (in development since 1992) that supports a wide range of widgets with native look-and-feel, and it has a very active community (ranked among the top 25 most active projects on sourceforge). Since most of the interface is automatically generated from the wxEiffel binding, the current release of wxHaskell already supports about 75% of the wxWindows functionality -- about 2900 methods in 500 classes with 1400 constant definitions. wxHaskell has been build with GHC 6.x on Windows, MacOS X and Unix systems with GTK. A binary distribution is available for Windows, Linux (RPM) and MacOS X. And even if you don't intend to write GUI's yourself, it will be fun to check out the screenshots at <http://wxhaskell.sourceforge.net>. ---------------------------------------------------------------------- Version 0.8 ----------- Non backward compatible changes: - Added wildcards argument to the "fileSaveDialog" function. - Removed the call to "buttonSetDefault" in the "defaultButton" property since GTK seems to enlarge the button in that case. - Removed alignment argument for text controls - Removed sorted and labels argument for choice and combo boxes. - Removed sorted argument for listboxes. - Added default "stretch" to every toplevel layout, assuring that such layout gets at least all available space assigned. - (un)set "maximize box" when "resizeable" is set. - Removed default "wxTAB_TRAVERSAL" style on frames (to make the grid work correctly). - Renamed "WXCore.WxcClassTypes" to "WXCore.WxcClassInfo". Backward compatible additions: - Added pure "bitmap" and "sound" - Added "variable" objects (mutable variables) - Added custom control demo. - Made "refresh" erase the background too. - Added "children" attribute for windows. - Added "border" attribute for windows. - Added "tabTraversal" attribute for windows. - Added wxGrid events and demo (samples/wx/Grid.hs). - Improved signatures for wxGrid. - Added "changes.txt" file :-) - Added "HAS_RADIO_MENU_ITEMS" to "isDefined". - Added support for radio menu items. - New wxHaskell+HOpenGL sample added to the contributions. Thanks to Shelarcy and Sean Seefried. - Added "Align" and "Wrapped" classes to set alignment and wrap mode for text controls. - Added "Sorted" class to set the sort mode of choice, combo box, and listbox controls. - Added "creation time" attributes that use reflective attributes not compositional (and thus not so nice), but very convenient! - Added "entry" as shorthand for "textEntry" - Added "SystemColor" and "colorSystem" to get standard system colors. - Defaulted background color of "Frame"s to Color3DFace (as a Panel). - Made the definition of "Closure" in "wrappers.h" more liberal to support wxOCaml better. - Added "frameCentre" method - Huge internal changes: split up wxcClasses in three files and added support for managed objects like bitmaps. Also added checks for NULL pointers. Bug fixes: - HtmlLinkClicked events are now properly generated. - Fixed bug that crashed wxHaskell when a tree control had the focus and a key was pressed. Thanks to Olivier Spier for sending a fix. - The "item" attribute of a list control always returned the first item and disregarded the parameter. Thanks to Olivier Spier for sending a fix.

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CFP: 4th Intl. Joint Conference AAMAS 2005 on Autonomous Agents & Multiagent Systems
by Matthias Klusch 26 Jul '04

26 Jul '04

+++ Apologies for multiple copies due to cross posting +++ Call for Papers ****************************************************** 4th International Joint Conference AAMAS on Autonomous Agents and Multiagent Systems July 25 - 29, 2005 Utrecht University, The Netherlands ****************************************************** http://www.aamas2005.nl Important dates =============== Electronic abstracts due: DECEMBER 6, 2004 Electronic paper submission deadline: DECEMBER 10, 2004 Notification: February 25, 2005 About the conference ==================== Agents are one of the most prominent and attractive technologies in computer science at the beginning of the new milennium. The technologies, methods, and theories of agents and multiagent systems are currently contributing to many diverse domains such as information retrieval, user interfaces, electronic commerce, robotics, computer mediated collaboration, computer games, education and training, ubiquitous computing, and social simulation. They not only are a very promising technology, but are also emerging as a new way of thinking, a conceptual paradigm for analyzing problems and for designing systems, for dealing with complexity, distribution, and interactivity, while providing a new perspective on computing and intelligence. The AAMAS conference series was initiated in 2002 as a merger of three highly successful related events: AGENTS (International Conference on Autonomous Agents), ICMAS (International Conference on Multi-Agent Systems), and ATAL (International Workshop on Agent Theories, Architectures, and Languages). The aim of the joint conference is to provide a single, high-profile, internationally renowned forum for research in the theory and practice of autonomous agents and multiagent systems. In particular, it brings together the world's researchers active in this important, vibrant, and rapidly growing field. AAMAS 2005 events include workshops and tutorials given by distinguished experts in the field, as well as an agent school, and doctoral mentoring program. Please check http://www.aamas2005.nl for latest information on the conference. Topics of interest ================== Topics of interest to AAMAS-05 include, but are not restricted to: * agents & complex systems; computational ecosystems * agent architectures; perception, action & planning in agents * agents & cognitive models * agents & networks: web agents, semantic web, grid, web services, P2P * agent communication: languages, semantics, pragmatics & protocols * agent-mediated electronic commerce & trading agents * agent-oriented software engineering & agent-oriented methodologies * agent programming languages, development environments & testbeds * applications of autonomous agents & multi-agent systems * artificial social systems; conventions, norms, social laws & institutions * autonomous robots & robot teams * coalition formation & teamwork; cooperative distributed problem solving * computational complexity in autonomous agents & multi-agent systems * cooperation & coordination; multi-agent planning * cooperative information systems, middle agents & brokers * distributed & multi-agent constraint satisfaction * game theoretic/economic foundations; algorithmic mechanism design * logics & formal models of agency; verification * multi-agent evolution, adaptation & learning * mobile agents * multi-agent simulation & modeling * negotiation, auctions, social choice mechanisms & argumentation * ontologies for agent systems * privacy & security issues in multi-agent systems * scalability & performance issues, robustness & dependability * synthetic agents; human-like, lifelike & believable qualities * theories of agency & autonomy * trust in agent systems; adjustable autonomy Submission ========== AAMAS-05 encourages the submission of theoretical, experimental, methodological, and applications papers. Theory papers should make clear the significance and relevance of their results to the AAMAS community. Similarly, applied papers should make clear both their scientific and technical contributions, and are expected to demonstrate a thorough evaluation of their strengths and weaknesses in practice. Papers that address isolated agent capabilities (for example, planning or learning) are discouraged unless they are placed in the overall context of autonomous agent architectures or multi-agent system organization and performance. A thorough evaluation is considered an essential component of any submission. Authors are also requested to make clear the implications of any theoretical and empirical results, as well as how their work relates to the state of the art in autonomous agents and multi-agent systems research as evidenced in, for example, previous AAMAS conferences. All submissions will be rigorously peer reviewed and evaluated on the basis of the quality of their technical contribution, originality, soundness, significance, presentation, understanding of the state of the art, and overall quality. In addition to conventional conference papers, AAMAS-05 also welcomes the submission of papers that focus on implemented systems, software, or robot prototypes. These papers require a demonstration of the prototype at the conference and should include a detailed project or system description specifying the hardware and software features and requirements. Please check http://www.aamas2005.nl/paper_submissions.htm for submission details. Organizing committee ==================== General co-chairs Sarit Kraus, Bar-Ilan University / University of Maryland Munindar Singh, North Carolina State University Program co-chairs Sven Koenig, University of Southern California Michael Wooldridge, University of Liverpool Local organization chair Frank Dignum, Utrecht University Local treasurer Virginia Dignum, Utrecht University Finance chair Sandip Sen, University of Tulsa Workshops chair Rino Falcone, ISTC - CNR Tutorials chair Onn Shehory, IBM Israel Demos co-chairs Omer Rana, Cardiff University Thomas Rist, FH Augsburg Doctoral mentoring chair Jürgen Dix, TU Clausthal Publicity chair Matthias Klusch, DFKI Sponsorship co-chairs Monique Calisti (Europe) Zakaria Maamar (Middle East) Kamal Karlapalem (South Asia) Jiming Liu (East Asia) Ana Lúcia Bazzan (Latin America) William Walsh (US & Canada) Publications chair Bin Yu, Carnegie Mellon University Student scholarship chair Barbara Keplicz, Warsaw University Exhibits chair Marie-Pierre Gleizes, IRIT, University Paul Sabatier

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