August 2008 - Haskell

Another First course in Haskell
by ppk＠cse.iitk.ac.in 22 Aug '08

22 Aug '08

Hi, I am planing a haskell based functional programming course. It is supposed to be a first course and I intend to show how real world applications can be built quite easily in haskell. Goals: 1) Cover all the basics like recursion, interesting data structures like zippers, monads 2) Haskell programming environment: by this I mean things like ghci, hadock, cabal The students after the course should seriously consider Haskell as a programming language for implementing their final year projects. In this aspect if one can convince that things like web-programming cgi scripting, networking, compiler projects, which are the favorits for programming projects, are better done in Haskell than in traditional languages like C and Java that would be a success. The course will be taken by mostly Computer Science undergrads. Any feed back is really welcome. I have about 2-3 months to plan the course. Regards ppk

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Re:Fwd: Haskell job opportunity: Platform Architect at
by Bert Mayo 21 Aug '08

21 Aug '08

Fat Chance. My resume has been knocking on their email mail box since last weekend. Apparently the mail box is already stuffed full with applications from eager Haskellers. Thousands of Haskellers chasing one job! Why don't some of you geniuses start businesses to employ some of this eager talent? --Bert Mayo >The message identifier is: 1KUz2g-0002tI-DO >The date of the message is: Mon, 18 Aug 2008 03:20:41 -0400 (GMT-04:00) >The subject of the message is: Haskell Job Opportunity >The address to which the message has not yet been delivered is: > hr(a)peerium.com

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Haskell Weekly News: Issue 82 - August 20, 2008
by Brent Yorgey 20 Aug '08

20 Aug '08

--------------------------------------------------------------------------- Haskell Weekly News http://sequence.complete.org/hwn/20080820 Issue 82 - August 20, 2008 --------------------------------------------------------------------------- Welcome to issue 82 of HWN, a newsletter covering developments in the [1]Haskell community. Announcements Lava2000 on Hackage. Emil Axelsson [2]announced that [3]Lava2000 has been uploaded to Hackage. Lava is a structural hardware description library embedded in Haskell. This version of Lava focuses on verification, and connects to a number of different verification engines (although only Smv and Satzoo are maintained in this version). QuickCheck and HPC Tutorial. Andy Gill [4]announced a half day tutorial on QuickCheck and HPC to be held at [5]DEFUN, taught by Andy Gill and Koen Claessen. The latest version of QuickCheck will also be released in conjunction with the tutorial. Compiler Construction course using Haskell?. Johannes Waldmann [6]announced that he plans to give a course in compiler construction, using Haskell as the implementation language. Any comments are appreciated, especially from anyone who has given or taken such a course. witness 0.1, open-witness 0.1. Ashley Yakeley [7]announced the release of these new packages and the draft paper on which they are based. posix-realtime 0.0.1. Vasili Galchin [8]announced the release of the posix-realtime package. benchpress 0.2.1. Johan Tibell [9]announced the first public release of [10]benchpress, a micro-benchmark library that produces statistics such as min, mean, standard deviation, median, and max execution time. wavconvert 0.1.1. Tim Chevalier [11]announced the release of [12]wavconvert, a tool which takes a directory tree as an argument, and converts any .wav files in it to .ogg (using an external OGG encoder) while filling in the ID3 tags based on the directory names. darcs hacking sprint (25-26 October). Eric Y. Kow [13]announced a darcs hacking sprint, to be held on the 25-26 of October, in Cambridge and Portland (and over IRC). The perfect opportunity to get involved, if you are interested in doing some hacking on darcs. Let Eric know if you are interested. X Haskell Bindings. Antoine Latter [14]announced that he is slowly [15]porting XCB (the X C Bindings) to Haskell, and would like input from any interested parties. logfloat. wren ng thornton [16]announced the release of the logfloat package for manipulating log-domain floating numbers. The main reason for casting numbers into the log-domain is to prevent underflow when multiplying many small probabilities as is done in Hidden Markov Models and other statistical models often used for natural language processing. The log-domain also helps prevent overflow when multiplying many large numbers. Roguestar 0.2.2. Christopher Lane Hinson [17]announced the release of version 0.2.2 of Roguestar. Google Summer of Code Progress updates from participants in the 2008 [18]Google Summer of Code. Hoogle 4. Neil Mitchell (ndm) is working on [19]Hoogle 4. [20]This week, he worked on getting out the last kinks to make [21]Hoogle 4 usable as a replacement for [22]Hoogle 3. Although this is the last official week of the GSoC, he plans to continue working on it when he has time. DPH physics engine. Roman Cheplyaka (Feuerbach) is working on a [23]physics engine using [24]Data Parallel Haskell. GHC plugins. Max Bolingbroke is working on dynamically loaded plugins for GHC. Cabal dependency framework. Andrea Vezzosi (Saizan) is working on a [25]make-like dependency analysis framework for Cabal. Language.C. Benedikt Huber (visq) is [26]working on Language.C, a standalone parser/pretty printer library for C99. Generic tries. Jamie Brandon is working on a library for efficient maps using generalized tries. GHC API. Thomas Schilling (nominolo) is working on [27]improvements to the GHC API. Jobs Platform Architect at Peerium, Inc.. Don Stewart [28]forwarded a job opportunity for a Haskell programmer at [29]Peerium, Inc. Peerium is building a new software platform for direct, real-time communication and collaboration within graphically rich environments, and is looking for a platform architect proficient in Haskell to work with the founders to design and implement components of the runtime and supporting libraries for our software platform. Resumes should be forwarded to hr [30]peerium.com. Blog noise [31]Haskell news from the [32]blogosphere. * Don Stewart: [33]The 500 Packages: Haskell, Distros, and Maintainership. * Neil Mitchell: [34]Hoogle New Features. Neil has finished his Google Summer of Code work on the [35]new version of Hoogle, but still intends to continue working on it when he gets the chance. A number of new features have been added. * Well-Typed.Com: [36]Solving the diamond dependency problem. Duncan explains how the newest version of Cabal (mostly) solves the DDDP (dreaded diamond dependency problem). * Real-World Haskell: [37]Two new chapters, preorder links, and a page count estimate. Two new beta chapters are up! * Dan Piponi (sigfpe): [38]Untangling with Continued Fractions: Part 1. Dan continues his fascinating series on rational tangles, showing how to describe a tangle using do-notation. * Christopher Lane Hinson: [39]ANN: Roguestar 0.2.2. * Luis Araujo: [40]Himerge (and Haskell) out to the street!. * Neil Mitchell: [41]GSoC Hoogle: Week 12. * Twan van Laarhoven: [42]A generic merge function. * Luke Palmer: [43]Slicing open the belly of the IO monad in an alternate universe. Luke explores methods of safely performing some I/O without the IO monad in the context of FRP. * Ketil Malde: [44]The wee beginnings of a biohaskell tutorial? -- and some thoughts on programming productivity. * Douglas M. Auclair (geophf): [45]Using Difference Lists. * Real-World Haskell: [46]Mid-August status update. Quotes of the Week * SimonM: People don't seem to believe me when I say this. In retrospect we shouldn't have called it forkOS, we should have called it forkReallyExpensiveOnlyNecessaryForCallingOpenGL_IO. * quicksilver: unsafeInterleaveIO gives you a way to cheat if you're happy to descend into a mire of programs with no semantics. * dmhouse: Eurgh, metastereo quotes. * quicksilver: [on @yhjulwwiefzojcbxybbruweejw] it's the noise a haskell developer makes if you kick him in the de bruijn index. About the Haskell Weekly News New editions are posted to [47]the Haskell mailing list as well as to [48]the Haskell Sequence and [49]Planet Haskell. [50]RSS is also available, and headlines appear on [51]haskell.org. To help create new editions of this newsletter, please see the information on [52]how to contribute. Send stories to byorgey at cis dot upenn dot edu. The darcs repository is available at darcs get [53]http://code.haskell.org/~byorgey/code/hwn/ . References 1. http://haskell.org/ 2. http://article.gmane.org/gmane.comp.lang.haskell.general/16381 3. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/chalmers-lava2000 4. http://article.gmane.org/gmane.comp.lang.haskell.general/16380 5. http://www.deinprogramm.de/defun-2008/ 6. http://article.gmane.org/gmane.comp.lang.haskell.general/16379 7. http://article.gmane.org/gmane.comp.lang.haskell.general/16376 8. http://article.gmane.org/gmane.comp.lang.haskell.cafe/43295 9. http://article.gmane.org/gmane.comp.lang.haskell.cafe/43292 10. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/benchpress 11. http://article.gmane.org/gmane.comp.lang.haskell.cafe/43282 12. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/wavconvert 13. http://article.gmane.org/gmane.comp.lang.haskell.cafe/43240 14. http://article.gmane.org/gmane.comp.lang.haskell.cafe/43230 15. http://community.haskell.org/~aslatter/code/xhb 16. http://article.gmane.org/gmane.comp.lang.haskell.cafe/43211 17. http://blog.downstairspeople.org/2008/08/16/ann-roguestar-022/ 18. http://hackage.haskell.org/trac/summer-of-code/wiki/SoC2008 19. http://code.haskell.org/hoogle/ 20. http://neilmitchell.blogspot.com/2008/08/gsoc-hoogle-week-12.html 21. http://haskell.org/hoogle/beta 22. http://haskell.org/hoogle 23. http://haskell.org/haskellwiki/Hpysics 24. http://www.haskell.org/haskellwiki/GHC/Data_Parallel_Haskell 25. http://code.haskell.org/~Saizan/cabal 26. http://www.sivity.net/projects/language.c/wiki/ 27. http://hackage.haskell.org/trac/ghc/wiki/GhcApiStatus 28. http://article.gmane.org/gmane.comp.lang.haskell.cafe/43175 29. http://www.peerium.com/ 30. file://localhost/home/brent/haskell/hwn/at] 31. http://planet.haskell.org/ 32. http://haskell.org/haskellwiki/Blog_articles 33. http://cgi.cse.unsw.edu.au/~dons/blog/2008/08/21#the_500 34. http://neilmitchell.blogspot.com/2008/08/hoogle-new-features.html 35. http://haskell.org/hoogle/ 36. http://blog.well-typed.com/2008/08/solving-the-diamond-dependency-problem/ 37. http://www.realworldhaskell.org/blog/2008/08/18/two-new-chapters-preorder-l… 38. http://sigfpe.blogspot.com/2008/08/untangling-with-continued-fractions_16.h… 39. http://blog.downstairspeople.org/2008/08/16/ann-roguestar-022/ 40. http://araujoluis.blogspot.com/2008/08/himerge-and-haskell-out-to-street.ht… 41. http://neilmitchell.blogspot.com/2008/08/gsoc-hoogle-week-12.html 42. http://twan.home.fmf.nl/blog/haskell/generic-merge.details 43. http://luqui.org/blog/archives/2008/08/14/slicing-open-the-belly-of-the-io-… 44. http://blog.malde.org/index.php/2008/08/14/the-wee-beginnings-of-a-biohaske… 45. http://logicaltypes.blogspot.com/2008/08/using-difference-lists.html 46. http://www.realworldhaskell.org/blog/2008/08/13/mid-august-status-update/ 47. http://www.haskell.org/mailman/listinfo/haskell 48. http://sequence.complete.org/ 49. http://planet.haskell.org/ 50. http://sequence.complete.org/node/feed 51. http://haskell.org/ 52. http://haskell.org/haskellwiki/HWN 53. http://code.haskell.org/~byorgey/code/hwn/

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ANNOUNCE: Lava2000 on Hackage
by Emil Axelsson 20 Aug '08

20 Aug '08

Hello, Lava2000 has been uploaded to Hackage: http://hackage.haskell.org/cgi-bin/hackage-scripts/package/chalmers-lava2000 Lava is a structural hardware description library embedded in Haskell. This version of Lava focuses on verification, and connects to a number of different verification engines (although only Smv and Satzoo are maintained in this version). For documentation, see the tutorial included in the package. The code is located at http://www.cs.chalmers.se/~emax/darcs/chalmers-lava2000/ People who have other modified versions of the library are welcome to submit patches, so that we get a single version that can be used by everyone. A different version of Lava, with focus on FPGA generation, can be found on Satnam Sing's page: http://raintown.org/lava/ / Emil

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QuickCheck and HPC Tutorial
by Andy Gill 20 Aug '08

20 Aug '08

Dear Haskellers, We would like to draw your attention to the following. At the DEFUN event (in conjunction with ICFP in Victoria in September), there will be a half day tutorial titled: Using QuickCheck and HPC - Obtaining Quality Assurance for Haskell Code The tutorial will be given by Andy Gill (Kansas University) and Koen Claessen (Chalmers), on Saturday, September 27 in the afternoon. The latest version of QuickCheck will also be released in conjunction with the tutorial. (If you cannot wait, you can find a development snapshot at http://code.haskell.org/QuickCheck/) For more information on DEFUN, look here: http://www.deinprogramm.de/defun-2008/ See you there! Andy and Koen

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Is this a feature or bug in the GADTs & ExistentialQuantification? (Was: [Haskell-cafe] Unboxing VT_VARIANT in hscom)
by Krasimir Angelov 20 Aug '08

20 Aug '08

The issue reported by Praki looks like a GHC bug to me. The smallest test case is at the end. (VarType a) is a GADT and Variant wraps the VarType with a value of type a. The definitions of Variant and VarType require ExistentialQuantification and GADTs extensions and I have declared them. The problem is when someone try to use them. If the client code is compiled without any extensions turned on the error message is: >> test.hs:35:47: >> Couldn't match expected type `IDispatch a' >> against inferred type `a1' >> `a1' is a rigid type variable bound by >> the constructor `Variant' at test.hs:34:22 >> In the second argument of `getMethodID', namely `idisp' >> In a 'do' expression: dispId <- getMethodID "ExecQuery" idisp >> In the expression: >> do dispId <- getMethodID "ExecQuery" idisp >> return () This suggests that the compiler understands that Variant is an existential type but doesn't understand that VarType is a GADT. If the code is compiled with -fglasgow-exts then everything works fine. Why the compiler always understands existential types and not GADT. For me this is unfair against GADT. Shouldn't the compiler always understand GADT as well provided that they are already defined somewhere? Best Regards, Krasimir ------------------------------------------------------------------------------ -- Implementation of Variant ------------------------------------------------------------------------------ {-# LANGUAGE ExistentialQuantification, GADTs #-} module Variant where data VarType a where VT_DISPATCH :: VarType IDispatch data IDispatch = IDispatch data Variant = forall a . Variant (VarType a) a ------------------------------------------------------------------------------ -- Use of Variant ------------------------------------------------------------------------------ import Variant useIDispatch :: IDispatch -> IO () useIDispatch _ = putStrLn "useIDispatch" useVariant (Variant VT_DISPATCH idisp) = useIDispatch idisp On Wed, Aug 20, 2008 at 9:58 AM, Krasimir Angelov <kr.angelov(a)gmail.com> wrote: > Aha. I got it. You should compile with -fglasgow-exts option. The > extra type signatures doesn't matter. > > > On Wed, Aug 20, 2008 at 8:20 AM, Praki Prakash <praki.prakash(a)gmail.com> wrote: >> Krasimir - thanks for your reply. I had tried explicit typing but I still >> get the same error. I have some code below and the error message. >> >> import Control.Exception >> import Foreign >> import Foreign.COM.Client >> import Foreign.COM.Automation >> import System.IO >> >> data WmiConnection = >> WmiConnection { >> execQuery :: String -> IO () >> } >> >> main = withCOM $ do >> conn <- wmiconnect "." "root\\cimv2" >> execQuery conn "Select * From ..." >> print "done" >> >> wmiconnect :: String -> String -> IO WmiConnection >> wmiconnect comp cimroot = >> do >> clsid <- progid2clsid "WbemScripting.SWbemLocator" >> (bracket (createInstance clsid iidIUnknown) release $ \iunkn -> >> bracket (queryInterface iidIDispatch iunkn) release $ \idisp -> do >> dispId <- getMethodID "ConnectServer" idisp >> withBSTR comp $ \pComputer -> >> withBSTR cimroot $ \pCimRoot -> do >> (res,args) <- invoke dispId InvokeMethod [Variant VT_BSTR >> pComputer, >> Variant VT_BSTR >> pCimRoot >> ] idisp >> print res >> let conn = WmiConnection{ execQuery = queryFunc res } >> return conn) >> where >> queryFunc :: Variant -> String -> IO () >> queryFunc (Variant VT_DISPATCH idisp) query = do >> dispId <- getMethodID "ExecQuery" idisp >> return () >> {- >> queryFunc (Variant vt idisp) query = >> if vt == VT_DISPATCH >> then do >> dispId <- getMethodID "ExecQuery" idisp >> return "" >> else >> fail "error" >> >> return () >> -} >> >> C:\>ghc --make test.hs >> [1 of 1] Compiling Main ( test.hs, test.o ) >> >> test.hs:35:47: >> Couldn't match expected type `IDispatch a' >> against inferred type `a1' >> `a1' is a rigid type variable bound by >> the constructor `Variant' at test.hs:34:22 >> In the second argument of `getMethodID', namely `idisp' >> In a 'do' expression: dispId <- getMethodID "ExecQuery" idisp >> In the expression: >> do dispId <- getMethodID "ExecQuery" idisp >> return () >> >> Any further suggestions? >> >> Thanks, >> Praki >> >> On Tue, Aug 19, 2008 at 1:49 AM, Krasimir Angelov <kr.angelov(a)gmail.com> >> wrote: >>> >>> This looks like a GHC bug to me. I am pretty sure that this worked >>> before. Variant is defined like this: >>> >>> data Variant = forall a . Variant (VarType a) a >>> >>> data VarType a where >>> .... >>> VT_DISPATCH :: VarType (IDispatch ()) >>> >>> From this it clear that val is of type (IDispatch ()) because the >>> VarType has value VT_DISPATCH. A workaround is to add explicit type >>> singnature for val: >>> >>> someFunc (Variant VT_DISPATCH val) query = do >>> dispId <- getMethodID "MethodName" (val :: IDispatch ()) >>> >>> I don't know why this doesn't work without the signature. >>> >>> Regards, >>> Krasimir >>> >>> >>> On Tue, Aug 19, 2008 at 7:09 AM, Praki Prakash <praki.prakash(a)gmail.com> >>> wrote: >>> > I am a Haskell newbie trying to do COM automation using Haskell. I am >>> > using >>> > hscom (Krasimir's implementation of COM automation). I have run into a >>> > problem >>> > and need some help. >>> > >>> > I have a Variant returned from a COM method invocation. When I print it, >>> > it >>> > shows up as below. >>> > >>> > Variant VT_DISPATCH <interface 0x00039f00> >>> > >>> > I need to invoke methods on the wrapped interface. My attempt to unbox >>> > it as >>> > below runs into 'rigid type' error. >>> > >>> > someFunc (Variant VT_DISPATCH val) query = do >>> > dispId <- getMethodID "MethodName" val >>> > >>> > The code above generates this error. >>> > >>> > Couldn't match expected type `IDispatch a' >>> > against inferred type `a1' >>> > `a1' is a rigid type variable bound by... >>> > >>> > I am probably missing something pretty basic. Any help on this is >>> > greatly >>> > appreciated! >>> > >>> > Thanks >>> > >>> > >>> > >>> > >>> > >>> > _______________________________________________ >>> > Haskell-Cafe mailing list >>> > Haskell-Cafe(a)haskell.org >>> > http://www.haskell.org/mailman/listinfo/haskell-cafe >>> > >> >> >

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ANN: witness 0.1, open-witness 0.1, "Witnesses and Open Witnesses"
by Ashley Yakeley 18 Aug '08

18 Aug '08

Two packages, and the draft paper on which they are based. Both packages are "proof of concept"; I'm open to ideas and repainting of bike-sheds. witness 0.1 A witness is a value that witnesses some sort of constraint on some list of type variables. This library provides support for simple witnesses, that constrain a type variable to a single type, and equality witnesses, that constrain two type variables to be the same type. The library also provides classes for representatives, which are values that represent types. For example, the equality witness type: data EqualType a b where MkEqualType :: EqualType t t If two simple witness values are the same, then their types are the same: class SimpleWitness w where matchWitness :: w a -> w b -> Maybe (EqualType a b) Hackage: <http://hackage.haskell.org/cgi-bin/hackage-scripts/package/witness> Source: <http://code.haskell.org/witness/> open-witness 0.1 Open witnesses (type IOWitness) are simple witnesses that can witness to any type. However, they cannot be constructed, they can only be generated in certain monads: newIOWitness :: IO (IOWitness a) We can also create fully heterogenous dictionaries that use open witnesses as keys. This would work as the state in an ST monad. If we had a "top-level" monad, or some other way of declaring unique IOWitness values at top level, we could straightforwardly and safely solve the expression problem (see below). In lieu of that, there's an unsafe function to construct them: unsafeIOWitnessFromString :: String -> IOWitness a This release includes an example re-implementation of ST/STRef, and a sound approximation of Typeable/Dynamic. Hackage: <http://hackage.haskell.org/cgi-bin/hackage-scripts/package/open-witness> Source: <http://code.haskell.org/open-witness/> Witnesses and Open Witnesses Abstract: We review witnesses, an emerging Haskell idiom, and suggest some terminology. We then introduce open witnesses as a library, and propose an extension to allow the creation of them at top-level. We show how this solves the expression problem, all with relatively little implementation fuss. draft, rejected from the Haskell Symposium 2008 <http://semantic.org/stuff/Open-Witnesses.pdf> -- Ashley Yakeley Seattle, WA

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Fwd: Haskell job opportunity: Platform Architect at Peerium, Inc.
by Don Stewart 14 Aug '08

14 Aug '08

Hey all, Below is a job opportunity for a Haskell programmer at Peerium, Inc. I was asked for forward to the community. Enjoy! -- Don ------------------------------------------------------------------------ Subject: Haskell Job Opportunity Platform Architect at Peerium, Inc. Please mail resumes to: hr(a)peerium.com Location: Cambridge, MA (Greater Boston Area) http://www.peerium.com Type: Full-time Skills: Proficiency and a strong interest in Haskell programming :) Bachelor's degree in computer science or equivalent from a four-year institution. Job Description Platform architects work with the founders to design and implement components of the runtime and supporting libraries for our software platform. Company Description At Peerium, we're striving to bring a new level of quality and efficiency to online communication and collaboration within virtual communities, social networks, and business environments. We believe that a new environment that supports the effortless sharing of both information and software will enable a level of online cooperation far beyond current Web-based technologies -- modern programming techniques will enable the creation of more robust and more powerful programs within these environments. ----- To this end, we're building a new software platform for direct, real- time communication and collaboration within graphically rich environments. We're currently building our first publicly available software product using many in-house technologies, including a powerful new programming language. Our first software product brings together a broad range of technologies, including: * Concurrent, distributed, functional programming * Graphically-rich, OpenGL interfaces * Peer-to-peer network protocols * Cryptographically secure communication * Distributed computation * Ubiquitous online agents ----- Peerium is located in the heart of Harvard Square in Cambridge, Massachusetts.

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CFP: PADL 2009
by Andy Gill 14 Aug '08

14 Aug '08

CALL FOR PAPERS!!! Eleventh International Symposium on Practical Aspects of Declarative Languages 2009 (PADL '09) http://cs.utdallas.edu/padl09/ Savannah Georgia, USA January 19-20, 2009 Co-located with ACM POPL'09 Declarative languages build on sound theoretical bases to provide attractive frameworks for application development. These languages have been successfully applied to vastly different real-world situations, ranging from data base management to active networks to software engineering to decision support systems. New developments in theory and implementation have opened up new application areas. At the same time, applications of declarative languages to novel problems raise numerous interesting research issues. Well-known questions include designing for scalability, language extensions for application deployment, and programming environments. Thus, applications drive the progress in the theory and implementation of declarative systems, and benefit from this progress as well. PADL is a forum for researchers and practitioners to present original work emphasizing novel applications and implementation techniques for all forms of declarative concepts, including, functional, logic, constraints, etc. Topics of interest include: * innovative applications of declarative languages; * declarative domain-specific languages and applications; * practical applications of theoretical results; * new language developments & their impact on applications; * evaluation of implementation techniques on practical applications; * novel uses of declarative languages in the classroom; and * practical experiences PADL 09 welcomes new ideas and approaches pertaining to applications and implementation of declarative languages. PADL 09 will be co-located with the ACM POPL. IMPORTANT DATES AND SUBMISSION GUIDELINES Paper Submission: September 8, 2008 Notification: October 10, 2008 Camera-ready: November 5, 2008 Symposium: January 19-20, 2009 Authors should submit an electronic copy of the full paper (written in English) in Postscript (Level 2) or PDF, in the Springer LNCS format (see http://www.springeronline.com/lncs/ ). In addition to the technical papers of previous PADL conferences, PADL 09 will contain a streamk for application papers. TECHNICAL PAPERS Technical papers must describe original, previously unpublished results, and must not be simultaneously submitted for publication elsewhere. Each submission must be written in English, and include three to four keywords, which will be used to assist us in selecting appropriate reviewers for the paper. Submissions must not exceed 15 pages in Springer LNCS format. APPLICATION PAPERS Application papers are a mechanism to present important practical applications of declarative languages that occur in industry or in areas of research other than computer science. Application papers will be published in the Springer-Verlag conference proceedings, and will be presented in a separate poster session. Application papers, are expected to describe complex and/or real-world applications that rely on an innovative use of declarative languages. Application descriptions, engineering solutions and real-world experiences (both positive and negative) are solicited. The limit for application papers is 3 pages in Springer LNCS format. MOST PRACTICAL PAPER AWARD The Most Practical Paper award will be given to the technical submission that is judged by the program committee to be the best in terms of practicality, originality, and clarity of presentation. The program committee may choose not to make an award, or to make multiple awards. PROGRAM COMMITTEE Lennart Augustsson Credit Suisse (UK) Hasan Davulcu Arizona State University (US) Inés Dutra Universidade do Porto (PT) John Gallagher Roskilde University (DK) Andy Gordon Microsoft Research (UK) Jeff Gray University of Alabama at Birmingham (US) Kevin Hamlen University of Texas at Dallas (US) Fergus Henderson Google (US) Gabriele Keller University of New South Wales (Australia) Michael Kifer SUNY Stony Brook (US) Ilkka Niemelä Helsinki University of Technology (FI) Johan Nordlander Luleå University of Technology (Sweden) Luís Pereira Universidade Nova de Lisboa (PT) Tom Schrijvers Katholieke Universiteit Leuven (BE) Lindsey Spratt Onology Works (US) Don Stewart Galois, Inc (US) Walter Wilson Systems Development and Analysis (US) Contacts: For information about papers and submissions, please contact a Program Chair: Andy Gill PC co-Chair - PADL 2009 Dept. of Electrical Engineering & Computer Science The University of Kansas 2001 Eaton Hall 1520 West 15th Street Lawrence, KS 66045-7621 Email: andygill <AT> ku.edu Terrance Swift PC co-Chair - PADL 2009 Centre for Artificial Intelligence (CENTRIA) Departamento de Informática, FCT/UNL Quinta da Torre 2829-516 CAPARICA - Portugal Email: tswift <AT> cs.sunysb.edu For other information about the conference, please contact: Kevin Hamlen General Chair - PADL 2009 Department of Computer Science University of Texas at Dallas Richardson, TX, USA Email: hamlen <AT> utdallas.edu

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Haskell Weekly News: Issue 81 - August 13, 2008
by Brent Yorgey 13 Aug '08

13 Aug '08

--------------------------------------------------------------------------- Haskell Weekly News http://sequence.complete.org/hwn/20080813 Issue 81 - August 13, 2008 --------------------------------------------------------------------------- Welcome to issue 81 of HWN, a newsletter covering developments in the [1]Haskell community. This week saw some interesting talks at [2]AngloHaskell, and some cool new packages to hit Hackage, like [3]Language.C, [4]AERN-Real, [5]FTGL, and [6]Hoogle. What are you waiting for? Get out there and build something! Announcements Initial release of Language.C (language-c-0.3). Benedikt Huber [7]announced the [8]first release of [9]Language.C, a library for analysing and generating C code. This release features a reasonably well tested parser, a pretty printer, and a preview of the analysis framework. darcs roadmap. Jason Dagit [10]wrote to the list to thank everyone for their support for darcs, and to announce a webpage with a [11]roadmap for future darcs features. Darcs is alive and well! Anglo Haskell 2008 -- slides and audio. Matthew Sackman [12]announced that [13]slides and audio from Anglo Haskell 2008 are now available. BLAS bindings for haskell, version 0.5. Patrick Perry [14]announced a new release of the Haskell BLAS bindings, including a number of new features and improvements. Tutorial on information visualization and visual analytics in Haskell. Jefferson Heard [15]announced the [16]tutorial he will be presenting at DEFUN 2008, to give everyone a sneak peek at the long version of the tutorial before he's done with it. Comments and questions are welcome and encouraged. interval and polynomial enclosure arithmetics. Michal Konecny [17]announced the release of the [18]AERN-Real and [19]AERN-RnToRm packages, which model and reasonably efficiently implement exact real arithmetic. FTGL 1.0. Portable truetype font rendering in OpenGL. Jefferson Heard [20]announced the release of [21]Haskell bindings to FTGL, an easy to use library for portable rendering of TrueType fonts in OpenGL. Google Summer of Code Progress updates from participants in the 2008 [22]Google Summer of Code. GHC plugins. Max Bolingbroke is working on dynamically loaded plugins for GHC. [23]This week, he gave [24]a talk at AngloHaskell. Language.C. Benedikt Huber (visq) is [25]working on Language.C, a standalone parser/pretty printer library for C99. This week, he [26]announced the [27]first release of the [28]Language.C package. Hoogle 4. Neil Mitchell (ndm) is working on [29]Hoogle 4. [30]This week, he released several [31]command-line versions and a [32]web version of Hoogle 4, updated the manual, and gave [33]a talk at AngloHaskell. Next week, he plans to work on generating better Hoogle databases, and some bug fixes. DPH physics engine. Roman Cheplyaka (Feuerbach) is working on a [34]physics engine using [35]Data Parallel Haskell. [36]This week, he added complete support for general polyhedra, and fixed some bugs in the collision handler. He also added support for bounding spheres, although the results so far are disappointing, due to delays in the GHC implementation of parallel arrays. Next week, he plans to implement static bodies and BSP trees. Generic tries. Jamie Brandon is working on a library for efficient maps using generalized tries. GHC API. Thomas Schilling (nominolo) is working on [37]improvements to the GHC API. Cabal dependency framework. Andrea Vezzosi (Saizan) is working on a [38]make-like dependency analysis framework for Cabal. Blog noise [39]Haskell news from the [40]blogosphere. * >>> Nicholas Lativy: [41]Haskell in less than five minutes. Nicholas refreshes his memory of Haskell. * Douglas M. Auclair (geophf): [42]Monoid use. * Roman Cheplyaka: [43]Status report: week 11-12. * Douglas M. Auclair (geophf): [44]Combinatory Birds as Types. * Douglas M. Auclair (geophf): [45]Getting Better, part ][. * Neil Mitchell: [46]GSoC Hoogle: Week 11. * Max Bolingbroke: [47]Compiler Plugins AngloHaskell Talk. * London Haskell Users Group: [48]Video: Paradise, a DSEL for Derivatives Pricing. * Roman Cheplyaka (Feuerbach): [49]Compiling GHC. Roman records his experiences building the latest development version of GHC. * Luke Palmer: [50]Mindfuck: The Reverse State Monad. * Dan Piponi (sigfpe): [51]Untangling with Continued Fractions: Part 0. * Joachim Breitner: [52]Xmonad on my mobile phone. * Luke Palmer: [53]Composable Input for Fruit. * >>> Louis: [54]A Gentle Introduction to Haskell. Louis is learning Haskell by working through the Gentle Introduction. * >>> Bryan St. Amour: [55]Some Project Euler. Bryan learns some Haskell the good old-fashioned way---by solving Project Euler problems. * Magnus Therning: [56]TagSoup, meet Parsec!. Magnus uses Parsec to parse streams of tags. * Thomas M. DuBuisson: [57]hsXenCtrl and pureMD5. * Alpheccar: [58]Haskell, iPhone and Biotech. * >>> codeflow: [59]About AI and neural networks. codeflow implements neural networks in Haskell for some soccer-playing AI software. * >>> Vincent Kriek: [60]And the winner is.... Vincent decides to stick with xmonad. * >>> Matthew Trinneer: [61]A New Paradigm - Haskell and HAppS. Quotes of the Week * Anatoly Yakovenko: theory doesn't scare me. i am using haskell after all, so i am used to reading long winded papers. * bwr: mapM_ putStrLn$reverse[(++)([1..y-30]>>" ")$concat$map([" "," /", " -", " \\"]!!)[(foldr(.)(scanl(+)1)([1..y]>>[scanl(+)0])[2..]!!(2*(1+y)+x) )`mod`4|x<-[-y-2..59-y*2]]|y<-[30..61]] About the Haskell Weekly News New editions are posted to [62]the Haskell mailing list as well as to [63]the Haskell Sequence and [64]Planet Haskell. [65]RSS is also available, and headlines appear on [66]haskell.org. To help create new editions of this newsletter, please see the information on [67]how to contribute. Send stories to byorgey at cis dot upenn dot edu. The darcs repository is available at darcs get [68]http://code.haskell.org/~byorgey/code/hwn/ . References 1. http://haskell.org/ 2. http://www.wellquite.org/anglohaskell2008/ 3. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/language%2Dc 4. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/AERN-Real 5. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/FTGL 6. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/hoogle 7. http://article.gmane.org/gmane.comp.lang.haskell.libraries/9809 8. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/language%2Dc 9. http://www.sivity.net/projects/language.c 10. http://www.haskell.org//pipermail/haskell-cafe/2008-August/045959.html 11. http://wiki.darcs.net/DarcsWiki/Roadmap 12. http://www.haskell.org//pipermail/haskell-cafe/2008-August/045986.html 13. http://www.wellquite.org/anglohaskell2008/ 14. http://article.gmane.org/gmane.comp.lang.haskell.cafe/43036 15. http://article.gmane.org/gmane.comp.lang.haskell.cafe/42994 16. http://bluheron.europa.renci.org/docs/BeautifulCode.pdf 17. http://article.gmane.org/gmane.comp.lang.haskell.general/16368 18. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/AERN-Real 19. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/AERN-RnToRm 20. http://article.gmane.org/gmane.comp.lang.haskell.cafe/42955 21. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/FTGL 22. http://hackage.haskell.org/trac/summer-of-code/wiki/SoC2008 23. http://blog.omega-prime.co.uk/2008/08/11/compiler-plugins-anglohaskell-talk/ 24. http://www.wellquite.org/anglohaskell2008/ 25. http://www.sivity.net/projects/language.c/wiki/ 26. http://article.gmane.org/gmane.comp.lang.haskell.libraries/9809 27. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/language%2Dc 28. http://www.sivity.net/projects/language.c 29. http://code.haskell.org/hoogle/ 30. http://neilmitchell.blogspot.com/2008/08/gsoc-hoogle-week-11.html 31. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/hoogle 32. http://haskell.org/hoogle/beta/ 33. http://www.wellquite.org/anglohaskell2008/ 34. http://haskell.org/haskellwiki/Hpysics 35. http://www.haskell.org/haskellwiki/GHC/Data_Parallel_Haskell 36. http://physics-dph.blogspot.com/2008/08/status-report-week-11-12.html 37. http://hackage.haskell.org/trac/ghc/wiki/GhcApiStatus 38. http://code.haskell.org/~Saizan/cabal 39. http://planet.haskell.org/ 40. http://haskell.org/haskellwiki/Blog_articles 41. http://blog.lativy.org/2008/08/13/haskell-in-less-than-five-minutes/ 42. http://logicaltypes.blogspot.com/2008/05/monoid-use.html 43. http://physics-dph.blogspot.com/2008/08/status-report-week-11-12.html 44. http://logicaltypes.blogspot.com/2008/08/combinatory-birds-as-types.html 45. http://logicaltypes.blogspot.com/2008/08/getting-better-part.html 46. http://neilmitchell.blogspot.com/2008/08/gsoc-hoogle-week-11.html 47. http://blog.omega-prime.co.uk/2008/08/11/compiler-plugins-anglohaskell-talk/ 48. http://www.londonhug.net/2008/08/11/video-paradise-a-dsel-for-derivatives-p… 49. http://ro-che.blogspot.com/2008/08/compiling-ghc.html 50. http://luqui.org/blog/archives/2008/08/10/mindfuck-the-reverse-state-monad/ 51. http://sigfpe.blogspot.com/2008/08/untangling-with-continued-fractions.html 52. https://www.joachim-breitner.de/blog/archives/300-Xmonad-on-my-mobile-phone… 53. http://luqui.org/blog/archives/2008/08/09/composable-input-for-fruit/ 54. http://lbks23.wordpress.com/2008/08/09/a-gentle-introduction-to-haskell/ 55. http://bryanstamour.com/?p=46 56. http://therning.org/magnus/archives/367 57. http://tommd.wordpress.com/2008/08/07/hsxenctrl-and-puremd5/ 58. http://www.alpheccar.org/en/posts/show/92 59. http://codeflow.wordpress.com/2008/08/03/about-ai-and-neural-networks/ 60. http://www.vincentkriek.nl/post/and-the-winner-is/ 61. http://thespohtexperiment.blogspot.com/2008/08/new-paradigm.html 62. http://www.haskell.org/mailman/listinfo/haskell 63. http://sequence.complete.org/ 64. http://planet.haskell.org/ 65. http://sequence.complete.org/node/feed 66. http://haskell.org/ 67. http://haskell.org/haskellwiki/HWN 68. http://code.haskell.org/~byorgey/code/hwn/

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