May 2009 - Haskell - Haskell.org

Announcing Djinn, version 2004-12-11, a coding wizard
by Lennart Augustsson 07 Apr '11

07 Apr '11

Howdy, y'all! I've written a small program that takes a (Haskell) type and gives you back a function of that type if one exists. It's kind of fun, so I thought I'd share it. It's probably best explained with a sample session. calvin% djinn Welcome to Djinn version 2005-12-11. Type :h to get help. # Djinn is interactive if not given any arguments. # Let's see if it can find the identity function. Djinn> f ? a->a f :: a -> a f x1 = x1 # Yes, that was easy. Let's try some tuple munging. Djinn> sel ? ((a,b),(c,d)) -> (b,c) sel :: ((a, b), (c, d)) -> (b, c) sel ((_, v5), (v6, _)) = (v5, v6) # We can ask for the impossible, but then we get what we # deserve. Djinn> cast ? a->b -- cast cannot be realized. # OK, let's be bold and try some functions that are tricky to write: # return, bind, and callCC in the continuation monad Djinn> type C a = (a -> r) -> r Djinn> returnC ? a -> C a returnC :: a -> C a returnC x1 x2 = x2 x1 Djinn> bindC ? C a -> (a -> C b) -> C b bindC :: C a -> (a -> C b) -> C b bindC x1 x2 x3 = x1 (\ c15 -> x2 c15 (\ c17 -> x3 c17)) Djinn> callCC ? ((a -> C b) -> C a) -> C a callCC :: ((a -> C b) -> C a) -> C a callCC x1 x2 = x1 (\ c15 _ -> x2 c15) (\ c11 -> x2 c11) # Well, poor Djinn has a sweaty brow after deducing the code # for callCC so we had better quit. Djinn> :q Bye. To play with Djinn do a darcs get http://darcs.augustsson.net/Darcs/Djinn or get http://darcs.augustsson.net/Darcs/Djinn/Djinn.tar.gz Then just type make. (You need a Haskell 98 implementation and some libraries.) And then start djinn. For the curious, Djinn uses a decision procedure for intuitionistic propositional calculus due to Roy Dyckhoff. It's a variation of Gentzen's LJ system. This means that (in theory) Djinn will always find a function if one exists, and if one doesn't exist Djinn will terminate telling you so. This is the very first version, so expect bugs. :) Share and enjoy. -- Lennart

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Call For Papers: APLAS 2009 (Korea, Dec 14-16, 2009)
by Zhenjiang Hu 09 Oct '09

09 Oct '09

=============================================================== FIRST CALL FOR PAPERS The Seventh Asian Symposium on Programming Languages and Systems (APLAS 2009) Seoul, December 14-16, 2009 http://ropas.snu.ac.kr/aplas09/ =============================================================== APLAS aims at stimulating programming language research by providing a forum for the presentation of recent results and the exchange of ideas and experience in topics concerned with programming languages and systems. APLAS is based in Asia, but is an international forum that serves the worldwide programming languages community. The APLAS series is sponsored by the Asian Association for Foundation of Software (AAFS), which has recently been founded by Asian researchers in cooperation with many researchers from Europe and the USA. The past formal APLAS symposiums were successfully held in Bangalore (2008, India), Singapore (2007), Sydney (2006, Australia), Tsukuba (2005, Japan), Taipei (2004, Taiwan) and Beijing (2003, China) after three informal workshops held in Shanghai (2002, China), Daejeon (2001, Korea) and Singapore (2000). Proceedings of the past symposiums were published in Springer-Verlag's LNCS 2895, 3302, 3780, 4279, and 5356. TOPICS: The symposium is devoted to both foundational and practical issues in programming languages and systems. Papers are solicited on, but not limited, to the following topics: * semantics, logics, foundational theory * type systems, language design * program analysis, optimization, transformation * software security, safety, verification * compiler systems, interpreters, abstract machines * domain-specific languages and systems * programming tools and environments INVITED SPEAKERS: TBA IMPORTANT DATES: Abstract Deadline: June 8 (Monday), 2009 Paper Submission Deadline: 24:00 AM (in Samoan Time), June 15 (Monday), 2009 Author Notification: August 17, 2009 Camera Ready: September 14, 2009 Conference: December 14-16, 2009 SUBMISSIONS INFORMATION: Papers should be submitted electronically online via the conference submission web page at URL <http://www.easychair.org/conferences/?conf=aplas2009>. Acceptable formats are PostScript or PDF, viewable by Ghostview or Adobe Reader. Submissions should not exceed 16 pages in LNCS format, including bibliography and figures. Submitted papers will be judged on the basis of significance, relevance, correctness, originality, and clarity. They should clearly identify what has been accomplished and why it is significant. Submitted papers must be unpublished and not submitted for publication elsewhere. The proceedings of the symposium is planned to be published as a volume in Springer-Verlag's Lecture Notes in Computer Science series. Authors of selected papers will be invited after the symposium to submit a full version for publication in a special issue of New Generation Computing. GENERAL CHAIR Kwangkeun Yi (Seoul National University, Korea) PROGRAM CHAIR Zhenjiang Hu (National Institute of Inforamtics, Japan) PROGRAM COMMITTEE Manuel M. T. Chakravarty (University of New South Wales, Australia) Wei-Ngan Chin (National University of Singapore, Singapore) Nate Foster (University of Pennsylvania, USA) Ralf Hinze (Oxford University, United Kingdom) Zhenjiang Hu (National Institute of Informatics, Japan), Chair Ik-Soon Kim (Electronics and Telecommunications Research Institute, Korea) Julia Lawall (DIKU, Denmark) Sebastian Maneth (NICTA and University of New South Wales, Australia) Sungwoo Park (Pohang University of Science and Technology, Korea) G. Ramalingam (Microsoft Research, India) Peter Thiemann (University of Freiburg, Germany) Kazushige Terui (Kyoto University, Japan) Janis Voigtländer (Technical University of Dresden, Germany) Chung-chieh Shan (Rutgers University, USA) Kazunori Ueda (Waseda University, Japan) Bow-Yaw Wang (Academia Sinica, Taiwan) Jianjun Zhao (Shanghai Jiaotong University, China) POSTER CHAIR Kiminori Matsuzaki (University of Tokyo, Japan)

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ANNOUNCE: ChristmasTree 0.1 (excuses for second attempt)
by S.Doaitse Swierstra 07 Jul '09

07 Jul '09

We are pleased to announce the availability of the package "ChristmasTree", which contains the code associated with our paper at the last Haskell symposium: @inproceedings{1411296, author = {Marcos Viera and S. Doaitse Swierstra and Eelco Lempsink}, title = {Haskell, do you read me?: constructing and composing efficient top-down parsers at runtime}, booktitle = {Haskell '08: Proceedings of the first ACM SIGPLAN symposium on Haskell}, year = {2008}, isbn = {978-1-60558-064-7}, pages = {63--74}, location = {Victoria, BC, Canada}, doi = {http://doi.acm.org/10.1145/1411286.1411296}, publisher = {ACM}, address = {New York, NY, USA}, } The name of the package stands for: "Changing Haskell's Read Implementation Such That by Manipulating Abstract Syntax Trees it Reads Expressions Efficiently" which, given the time of year, seems appropriate. Feel free to download and unpack this "present" at what for the Dutch is called "Sinterklaasavond" (http://en.wikipedia.org/wiki/Sinterklaas) Arthur Baars Marcos Viera Eelco Lempsink Doaitse Swierstra PS: the package uses our library supporting transformation of typed abstract syntax, which we placed in a separate package TTTAS

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Help with cabal and windows
by newuser21 30 May '09

30 May '09

Hi, I am new to haskell. I have an programm whitch i want to compile for windows .It has cabal .I installed haskellplatform for windows, and runhaskell setup.lhs configure runs fine.BUT when runhaskell setup.lhs build, then errors: Could not find module `Data.Generics': it is a member of the hidden package `base-3.0.3.1' it is a member of the hidden package `syb' WHY? syb is in the haskellplatform path?? I think it has something to do with paths? Oh and on linux no problems. All worked fine compiles with no error.But the same happends as I installed haskellplatform under wine and tryied to build the program. Thanks newuser -- View this message in context: http://www.nabble.com/Help-with-cabal-and-windows-tp23790447p23790447.html Sent from the Haskell - Haskell mailing list archive at Nabble.com.

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Leak in Data.Generics (syb-0.1.0.1, GHC 6.10.2)
by Paul L 30 May '09

30 May '09

I traced a memory leak to the use of Data.Genrics from the syb-0.1.0.1 package in GHC 6.10.2. But I'm not sure if it's syb package or this version of GHC's problem. Since I don't have a small program to demonstrate this leak, I'm just going to explain what I did, and hopefully some other users could help to identify this problem. I have the following line as part of a CGI program (sample1): output $ writeHtmlString' $ wikiLinksTransform $ readMarkdown' $ ... where output is from Network.CGI, and writeHtmlString' and readMarkdown' are variations of functions from Pandoc. wikiLinksTransfrom is a generic tranversal (modified from a similar function in Gitit) using Data.Generics over the Pandoc data structure. I compile my program in GHC 6.10.2 with -prof, run it with +RTS -hc -RTS, and plot the memory usage over a certain length of time. I noticed the memory for Text.Pandoc.Definition.CAF keeps increasing, which is wrong because my program is never holding the result of the above output. After some lengthy debugging, I came to the above line and removed wikiLinksTransform (sample2): output $ writeHtmlString' $ readMarkdown' $ ... The I profiled the memory again, there is no more leak! To further investigate the problem, I compiled my program with GHC 6.8.3, and this time even sample1 had no leak. Note that GHC 6.8.3's Data.Generics was from base-3.0 package, not syb. So I'm not sure if it's GHC's problem or syb's. I'm almost certain that Gitit users would have met similar problems, but I'm just too much overloaded to come up with a shorter code to file a proper bug report. So I'm posting here and hopefully somebody could follow up and eventually have this bug fixed. -- Regards, Paul Liu Yale Haskell Group http://www.haskell.org/yale

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IFL 2009: Second Call for Papers
by IFL 2009 29 May '09

29 May '09

Call for Papers IFL 2009 Seton Hall University SOUTH ORANGE, NJ, USA http://tltc.shu.edu/blogs/projects/IFL2009/ ** NEW ** Accomodations information available: http://tltc.shu.edu/blogs/projects/IFL2009/accommodations.html Jane Street Capital has joined IFL 2009 as a sponsor ********* The 21st International Symposium on Implementation and Application of Functional Languages, IFL 2009, will be held for the first time in the USA. The hosting institution is Seton Hall University in South Orange, NJ, USA and the symposium dates are September 23-25, 2009. It is our goal to make IFL a regular event held in the USA and in Europe. The goal of the IFL symposia is to bring together researchers actively engaged in the implementation and application of functional and function-based programming languages. IFL 2009 will be a venue for researchers to present and discuss new ideas and concepts, work in progress, and publication-ripe results related to the implementation and application of functional languages and function-based programming. Following the IFL tradition, IFL 2009 will use a post-symposium review process to produce a formal proceedings which will be published by Springer in the Lecture Notes in Computer Science series. All participants in IFL 2009 are invited to submit either a draft paper or an extended abstract describing work to be presented at the symposium. These submissions will be screened by the program committee chair to make sure they are within the scope of IFL and will appear in the draft proceedings distributed at the symposium. Submissions appearing in the draft proceedings are not peer-reviewed publications. After the symposium, authors will be given the opportunity to incorporate the feedback from discussions at the symposium and will be invited to submit a revised full arcticle for the formal review process. These revised submissions will be reviewed by the program committee using prevailing academic standards to select the best articles that will appear in the formal proceedings. TOPICS IFL welcomes submissions describing practical and theoretical work as well as submissions describing applications and tools. If you are not sure if your work is appropriate for IFL 2009, please contact the PC chair at ifl2009(a)shu.edu. Topics of interest include, but are not limited to: language concepts type checking contracts compilation techniques staged compilation runtime function specialization runtime code generation partial evaluation (abstract) interpretation generic programming techniques automatic program generation array processing concurrent/parallel programming concurrent/parallel program execution functional programming and embedded systems functional programming and web applications functional programming and security novel memory management techniques runtime profiling and performance measurements debugging and tracing virtual/abstract machine architectures validation and verification of functional programs tools and programming techniques FP in Education PAPER SUBMISSIONS Prospective authors are encouraged to submit papers or extended abstracts to be published in the draft proceedings and to present them at the symposium. All contributions must be written in English, conform to the Springer-Verlag LNCS series format and not exceed 16 pages. The draft proceedings will appear as a technical report of the Department of Mathematics and Computer Science of Seton Hall University. IMPORTANT DATES Registration deadline August 15, 2009 Presentation submission deadline August 15, 2009 IFL 2009 Symposium September 23-25, 2009 Submission for review process deadline November 1, 2009 Notification Accept/Reject December 22, 2009 Camera ready version February 1, 2010 PROGRAM COMMITTEE Peter Achten University of Nijmegen, The Netherlands Jost Berthold Philipps-Universität Marburg, Germany Andrew Butterfield University of Dublin, Ireland Robby Findler Northwestern University, USA Kathleen Fisher AT&T Research, USA Cormac Flanagan University of California at Santa Cruz, USA Matthew Flatt University of Utah, USA Matthew Fluet Toyota Technological Institute at Chicago, USA Daniel Friedman Indiana University, USA Andy Gill University of Kansas, USA Clemens Grelck University of Amsterdam/Hertfordshire, The Netherlands/UK Jurriaan Hage Utrecht University, The Netherlands Ralf Hinze Oxford University, UK Paul Hudak Yale University, USA John Hughes Chalmers University of Technology, Sweden Patricia Johann University of Strathclyde, UK Yukiyoshi Kameyama University of Tsukuba, Japan Marco T. Morazán (Chair) Seton Hall University, USA Rex Page University of Oklahoma, USA Fernando Rubio Universidad Complutense de Madrid, Spain Sven-Bodo Scholz University of Hertfordshire, UK Manuel Serrano INRIA Sophia-Antipolis, France Chung-chieh Shan Rutgers University, USA David Walker Princeton University, USA Viktória Zsók Eötvös Loránd University, Hungary PETER LANDIN PRIZE The Peter Landin Prize is awarded to the best paper presented at the symposium every year. The honored article is selected by the program committee based on the submissions received for the formal review process. The prize carries a cash award equivalent to 150 euros.

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CFP: APLAS 2009 (Abstracts due: June 8; Papers due: June 15)
by Janis Voigtlaender 29 May '09

29 May '09

=============================================================== CALL FOR PAPERS The Seventh Asian Symposium on Programming Languages and Systems (APLAS 2009) Seoul, December 14-16, 2009 http://ropas.snu.ac.kr/aplas09/ =============================================================== APLAS aims at stimulating programming language research by providing a forum for the presentation of recent results and the exchange of ideas and experience in topics concerned with programming languages and systems. APLAS is based in Asia, but is an international forum that serves the worldwide programming languages community. The APLAS series is sponsored by the Asian Association for Foundation of Software (AAFS), which has recently been founded by Asian researchers in cooperation with many researchers from Europe and the USA. The past formal APLAS symposiums were successfully held in Bangalore (2008, India), Singapore (2007), Sydney (2006, Australia), Tsukuba (2005, Japan), Taipei (2004, Taiwan) and Beijing (2003, China) after three informal workshops held in Shanghai (2002, China), Daejeon (2001, Korea) and Singapore (2000). Proceedings of the past symposiums were published in Springer-Verlag's LNCS 2895, 3302, 3780, 4279, and 5356. TOPICS: The symposium is devoted to both foundational and practical issues in programming languages and systems. Papers are solicited on, but not limited, to the following topics: * semantics, logics, foundational theory * type systems, language design * program analysis, optimization, transformation * software security, safety, verification * compiler systems, interpreters, abstract machines * domain-specific languages and systems * programming tools and environments INVITED SPEAKERS: TBA IMPORTANT DATES: Abstract Deadline: June 8 (Monday), 2009 Paper Submission Deadline: 24:00 AM (in Samoan Time), June 15 (Monday), 2009 Author Notification: August 17, 2009 Camera Ready: September 14, 2009 Conference: December 14-16, 2009 SUBMISSIONS INFORMATION: Papers should be submitted electronically online via the conference submission web page at URL <http://www.easychair.org/conferences/?conf=aplas2009>. Acceptable formats are PostScript or PDF, viewable by Ghostview or Adobe Reader. Submissions should not exceed 16 pages in LNCS format, including bibliography and figures. Submitted papers will be judged on the basis of significance, relevance, correctness, originality, and clarity. They should clearly identify what has been accomplished and why it is significant. Submitted papers must be unpublished and not submitted for publication elsewhere. The proceedings of the symposium is planned to be published as a volume in Springer-Verlag's Lecture Notes in Computer Science series. Authors of selected papers will be invited after the symposium to submit a full version for publication in a special issue of New Generation Computing. GENERAL CHAIR Kwangkeun Yi (Seoul National University, Korea) PROGRAM CHAIR Zhenjiang Hu (National Institute of Inforamtics, Japan) PROGRAM COMMITTEE Manuel M. T. Chakravarty (University of New South Wales, Australia) Wei-Ngan Chin (National University of Singapore, Singapore) Nate Foster (University of Pennsylvania, USA) Ralf Hinze (Oxford University, United Kingdom) Zhenjiang Hu (National Institute of Informatics, Japan), Chair Ik-Soon Kim (Electronics and Telecommunications Research Institute, Korea) Julia Lawall (DIKU, Denmark) Sebastian Maneth (NICTA and University of New South Wales, Australia) Sungwoo Park (Pohang University of Science and Technology, Korea) G. Ramalingam (Microsoft Research, India) Peter Thiemann (University of Freiburg, Germany) Kazushige Terui (Kyoto University, Japan) Janis Voigtländer (Technical University of Dresden, Germany) Chung-chieh Shan (Rutgers University, USA) Kazunori Ueda (Waseda University, Japan) Bow-Yaw Wang (Academia Sinica, Taiwan) Jianjun Zhao (Shanghai Jiaotong University, China) POSTER SESSION CHAIR Kiminori Matsuzaki (University of Tokyo, Japan)

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ANNOUNCE: Hac φ: Haskell hackathon in Philadelphia, July 24-26
by Brent Yorgey 28 May '09

28 May '09

Greetings, I am very pleased to officially announce Hac phi, a Haskell hackathon/get-together to be held July 24-26 at the University of Pennsylvania in Philadelphia. The hackathon will officially kick off at 2:30 Friday afternoon, and go until 5pm on Sunday (with breaks for sleep, of course). Thanks to everyone who has already expressed interest in attending, it's shaping up to be a fun event. I want to stress that everyone is welcome---you do not have to be a Haskell guru to attend! Helping hack on someone else's project could be a great way to increase your Haskell-fu. If you plan on coming, please officially register [1], even if you already put your name on the wiki. Registration, travel, lodging and many other details can now be found on the Hac phi wiki [2]. We're also looking for a few people interested in giving short (15-20 min.) talks, probably on Saturday afternoon. Anything of interest to the Haskell community is fair game---a project you've been working on, a paper, a quick tutorial. If you'd like to give a talk, add it on the wiki [3]. Hope to see you in Philadelphia! -The Hac φ team [1] http://haskell.org/haskellwiki/Hac_%CF%86/Register [2] http://haskell.org/haskellwiki/Hac_%CF%86 [3] http://haskell.org/haskellwiki/Hac_%CF%86/Talks

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DEFUN09: Final Call for Talks & Tutorials (co-located w/ ICFP09)
by Matthew Fluet (ICFP Publicity Chair) 28 May '09

28 May '09

Call for Talks and Tutorials ACM SIGPLAN 2009 Developer Tracks on Functional Programming http://www.defun2009.info/ Edinburgh, Scotland, September 3 and 5, 2009 The workshop will be held in conjunction with ICFP 2009 http://www.cs.nott.ac.uk/~gmh/icfp09.html Important dates Proposal Deadline: June 5, 2009 Notification: June 19, 2009 This is a second invitation to submit talk and tutorial proposals for DEFUN 2009, the ICFP 2009 Developer Tracks. The deadline for submissions is next Friday, June 5. We want to know about your favorite programming techniques, powerful libraries, and engineering approaches you've used that the world should know about and apply to other projects. We want to know how to be productive using functional programming, write better code, and avoid common pitfalls. DEFUN is contiguous with CUFP 2009, the goal of which is to build a community for users of functional programming languages and technology. DEFUN provides the more technical, teaching-oriented parts of functional programming, while CUFP focuses on the commercial, management, and software engineering aspects. For more details of the kinds of proposals we would like to see, and how to submit, please see our original call for proposals at http://www.defun2009.info/blog/call-for-talks-and-tutorials/

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[FMICS 2009] Call for Posters
by FMICS 2009 workshop chair 27 May '09

27 May '09

FMICS 2009 - CALL FOR POSTERS Please visit: http://users.dsic.upv.es/workshops/fmics2009 ************************************************************ * 14th International Workshop on * * Formal Methods for Industrial Critical Systems * * FMICS 2009 * * * * November 2-3, 2009 * * Eindhoven, The Netherlands * ************************************************************ * ** IMPORTANT DATES ** * * * * Submission deadline: June 5, 2009 * * Notification: June 20, 2009 * * Camera-ready version: July 15, 2009 * * Workshop: November 2-3, 2009 * * * ************************************************************ * * * +============================================+ * * | | * * | ** FMweek ** | * * | | * * +============================================+ * * | CPA | FACS | FAST | * * +--------------------------------------------+ * * | FM2009 | FMCO | FMICS | * * +--------------------------------------------+ * * | PDMC | REFINE | TESTCOM/FATES | * * +--------------------------------------------+ * * | http://www.win.tue.nl/fmweek | * * +============================================+ * * * ************************************************************

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