October 2009 - Haskell

ANN: HoleyMonoid-0.1
by Martijn van Steenbergen 26 Oct '09

26 Oct '09

Hello! I'm happy to announce the first release of HoleyMonoid, a datatype that helps you build monoids with holes in them. The holes are filled in later using normal function application. For example: > > let holey = now "x = " > . later show > . now ", y = " > . later show > > run holey 3 5 > "x = 3, y = 5" The library is available on Hackage: http://hackage.haskell.org/package/HoleyMonoid Thanks to David Menendez for the name and Sjoerd Visscher for help with rewriting and simplifying. :-) Martijn.

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ANNOUNCE: xmonad 0.9 is now available!
by Don Stewart 26 Oct '09

26 Oct '09

http://xmonad.org The xmonad dev team is pleased to announce xmonad 0.9! We think this is a great release. The headlines: * Actions.SpawnOn: Windows go to the workspace they were launched on, even if you're no longer viewing that workspace. Especially handy for slow-launching applications like Firefox * Actions.GridSelect: graphically go to, select, do things with windows, workspaces, prompts ... * Many new window layouts: http://is.gd/4BzAI * Many new scriptable actions: http://is.gd/4BzCN * Focus changes across screens with mouse movement, no longer requiring a click, even for empty workspaces. * Improved xmobar/dzen statusbar functions, easier to use, more compositional * New --restart command line flag to restart a running xmonad process. * Supports for multi-module local configuration files * Support for user-defined X event handling * xmonad comes with 180 extensions for enhancing functionality * Over 3000 commits have been made to the project. Extensive change logs: http://haskell.org/haskellwiki/Xmonad/Notable_changes_since_0.8 About: xmonad is a leading tiling window manager, known for its lightness, reliability, extensibility and efficiency. It supports true multiheaded tiling, and rich, rapid customisation. It is also highly portable, running on regular desktops, laptops, netbooks, phones, game consoles, the OLPC, and more. Features: * Very stable, fast, small and simple. * Automatic window tiling and management * First class keyboard support: a mouse is unnecessary * Full support for tiling windows on multi-head displays * Full support for floating, tabbing and decorated windows * Full support for Gnome and KDE utilities * XRandR support to rotate, add or remove monitors * Per-workspace layout algorithms * Per-screens custom status bars * Compositing support * Powerful, stable customisation and reconfiguration * Large extension library * Excellent, extensive documentation * Large, active development team, support and community Get it! Information, screenshots, documentation, tutorials and community resources are available from the xmonad home page: http://xmonad.org The 0.9 release, and its dependencies, are available from hackage.haskell.org: http://hackage.haskell.org/package/xmonad xmonad packages are available in pretty much every package system, including. Debian, Gentoo, Arch, Ubuntu, OpenBSD, NetBSD, FreeBSD, Gobo, NixOS, Source Mage, Slackware and 0.9 packages will appear in coming days (some are already available). On the fly updating to xmonad 0.9 is supported, without losing your session! You can even use cabal-install: $ cabal update $ cabal install xmonad-0.9 $ cabal install xmonad-contrib-0.9 $ xmonad --recompile mod-q Extensions: xmonad comes with a huge library of extensions (now around 15 times the size of xmonad itself), contributed by viewers like you. Extensions allow for all sorts of functionality and enhancements to the window manager, via Haskell in your config file. For more information on using and writing extensions see the webpage. The library of extensions is available from hackage: http://hackage.haskell.org/cgi-bin/xmonad-contrib Full documentation for using and writing your own extensions: http://xmonad.org/documentation.html This release brought to you by the xmonad dev team: Spencer Janssen Don Stewart Adam Vogt Brent Yorgey Daniel Wagner Devin Mullins Daniel Schoepe Braden Shepherdson Nicolas Pouillard Roman Cheplyaka Gwern Branwen Lukas Mai Featuring code contributions from over 80 developers: Aaron Denney Jason Creighton Alec Berryman Alex Tarkovsky Alexandre Buisse Andrea Rossato Austin Seipp Bas van Dijk Ben Voui Brandon Allbery Chris Mears Christian Thiemann Clemens Fruhwirth Daniel Neri Anders Engstrom Dave Harrison David Glasser David Lazar Dmitry Kurochkin Dominik Bruhn Dougal Stanton Eric Mertens Ferenc Wagner Jan Vornberger Hans Philipp Annen Ivan Tarasov Ivan Veselov Jamie Webb Jeremy Apthorp Malebria Joachim Breitner Joachim Fasting Joe Thornber Joel Suovaniemi Juraj Hercek Justin Bogner Kai Grossjohann Karsten Schoelzel Klaus Weidner Mathias Stearn Mats Jansborg Matsuyama Tomohiro Michael Fellinger Michael Sloan Miikka Koskinen Neil Mitchell Nelson Elhage Nick Burlett Quentin Moser Nils Anders Danielsson Peter De Wachter Robert Marlow Sam Hughes Shachaf Ben-Kiki Shae Erisson Simon Peyton Jones Stefan O'Rear Tom Rauchenwald Valery V. Vorotyntsev Will Farrington Yaakov Nemoy timthelion Rickard Gustafson Trevor Elliott Ian Zerny Ivan Miljenovic Marco e Silva Michal Janeczek David Roundy Wirt Wolff Max Rabkin Sean Escriva Norbert Zeh Alexey Khudyakov Ismael Carnales Luis Cabellos Konstantin Sobolev Dmitry Astapov Andres Salomon Aleksandar Dimitrov Ilya Portnov Michal Trybus Travis Hartwell As well as the support of many others on the #xmonad and #haskell IRC channels, and the wider Haskell and window manager communities. Thanks to everyone for their support!

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Haskell Weekly News: Issue 136 - October 24, 2009
by jfredett＠gmail.com 24 Oct '09

24 Oct '09

--------------------------------------------------------------------------- Haskell Weekly News http://sequence.complete.org/hwn/20091024 Issue 136 - October 24, 2009 --------------------------------------------------------------------------- Welcome to issue 136 of HWN, a newsletter covering developments in the [1]Haskell community. Short one this week, I have GREs today, so I've spent more time aggregating GRE knowledge rather than Haskell news. Till next week, Haskellers, The Haskell Weekly News! Announcements PastePipe -- a CLI for hpaste instances. Rogan Creswick [2]announced a new version of PastePipe, a library which reads from stdin and posts it to an hpaste instance (defaulting to hpaste.org) haskell-src-exts-1.2.0. Niklas Broberg [3]announced a major release of haskell-src-exts. Several breaking changes, a few (ideally) backwards compatable changes. See the post for all the details. mecha-0.0.0. Tom Hawkins [4]announced a very cool new DSL in Haskell for Constructive Solid Modelling. GPipe 1.02 and Vec-Transform 1.0.1. Tobias Bexelius [5]announced new versions of these packages, only a few API changes Data.Stream 0.4. Wouter Swierstra [6]announced a very delicate change to Data.Stream involving irrefutable patterns. Specifically added them in functions which produce new streams from old. strptime bindings. Eugene Kirpichov [7]announced bindings to strptime. cereal-0.2. Trevor Elliott [8]announced a new version of the cereal library, a variation on the `binary` package which provides strict parsing. quickcheck-poly. Ki Yung Ahn [9]announced a package for testing polymorphic functions automatically. 2nd CFP: JSC Special Issue on Automated Verification and Specification of Web Systems. demis [10]announced a special issue of the Journal of Symbolic Computation. The issue contains articles relating to Automated Specification and Verification of Web Systems. qtHaskell-1.1.3. David Harley [11]announced a new version of qtHaskell. Discussion Is there in Haskell the eval function? Waldemar Biernacki [12]asked about an `eval` function for Haskell. What's this pattern called? Martijn van Steenbergen [13]asked about a common pattern for an simple EDSL AST-like type. Problems with Haskell. Philippos Apolinarius [14]forwarded his response to a [15]Clean programmer who planned a move to Haskell upon fears of Clean being around for the long term. A very nice read. Statically checked binomail heaps? Maciej Kotowicz [16]talked about his implementation of Statically Checked Binomial Heaps in Haskell Blog noise [17]Haskell news from the [18]blogosphere. Blog posts from people new to the Haskell community are marked with >>>, be sure to welcome them! * Mikael Vejdemo Johansson (Syzygy-): [19][MATH198] Lecture 5 is up. * JP Moresmau: [20]Releasing my code on the unsuspecting public (EclipseFP). * Neil Brown: [21]Benchmarking STM with Criterion. * Galois, Inc: . * Brent Yorgey: [22]Typeclassopedia in Japanese!. * Neil Brown: [23]An early look at ThreadScope, a tool for profiling concurrent and parallel Haskell programs. * FP-Syd: [24]Sydney FP Group: FP-Syd #19.. * Michael Snoyman: [25]Monadic pairs and Kleisli arrows. * Martijn van Steenbergen: [26]Transforming polymorphic values. * Manuel M T Chakravarty: [27]Multicore Haskell Now!. * Don Stewart (dons): [28]Multicore Haskell Now! ACM Reflections | Projections 2009. * Dan Piponi (sigfpe): [29]What Category do Haskell Types and Functions Live In?. * Manuel M T Chakravarty: [30]Don Stewart's talk on Domain Specific Languages and Haskell. Quotes of the Week * Veinor: I program in austere haskell. I name all my variables a, a', a'', a''', etc * ddarius: releases network version 127.0.0.1 * Berengal: 'Bobby Boolean felt horrible. What did he ever do to the other values? He was just a simple bit, a simple answer to a simple question! Suddenly he felt his insides churn; he felt an exception coming on! Oh no! What should he do, now that he was outside of IO?' * Berengal: '"Go away! You're not like us!" the other values yelled. "You're impure! Impure! Impure! Impure!" they started chanting.' * dpratt71: <dpratt71> so I read somewhere that the unofficial motto of Haskell was "avoid success at all costs"... <Baughn> dpratt71: Yeah. We failed. * Warrigal: Note to self: don't do maximum [1..]. * mauke: the first and foremost task of a haskell compiler is to break haskell programs * ksf: ...premature generalisation is the root of all procrastination. * jimi_hendrix: that took longer than it should have, but it feels so pure * ddarius: Unfortunately, the logic programming community has this unhealthy death grip on Prolog. About the Haskell Weekly News New editions are posted to [31]the Haskell mailing list as well as to [32]the Haskell Sequence and [33]Planet Haskell. [34]RSS is also available, and headlines appear on [35]haskell.org. To help create new editions of this newsletter, please see the information on [36]how to contribute. Send stories to jfredett . at . gmail . dot . com. The darcs repository is available at darcs get [37]http://patch-tag.com/r/jfredett/HWN2/pullrepo HWN2 . References Visible links 1. http://haskell.org/ 2. http://article.gmane.org/gmane.comp.lang.haskell.cafe/65222 3. http://article.gmane.org/gmane.comp.lang.haskell.cafe/65219 4. http://article.gmane.org/gmane.comp.lang.haskell.cafe/65134 5. http://article.gmane.org/gmane.comp.lang.haskell.cafe/65119 6. http://article.gmane.org/gmane.comp.lang.haskell.cafe/65116 7. http://article.gmane.org/gmane.comp.lang.haskell.cafe/65061 8. http://article.gmane.org/gmane.comp.lang.haskell.cafe/65043 9. http://article.gmane.org/gmane.comp.lang.haskell.general/17586 10. http://article.gmane.org/gmane.comp.lang.haskell.general/17585 11. http://article.gmane.org/gmane.comp.lang.haskell.general/17583 12. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/65153 13. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/65148 14. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/65014 15. http://clean.cs.ru.nl/ 16. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/64998 17. http://planet.haskell.org/ 18. http://haskell.org/haskellwiki/Blog_articles 19. http://blog.mikael.johanssons.org/archive/2009/10/math198-lecture-5-is-up/ 20. http://jpmoresmau.blogspot.com/2009/10/releasing-my-code-on-unsuspecting.ht… 21. http://chplib.wordpress.com/2009/10/21/benchmarking-stm-with-criterion/ 22. http://byorgey.wordpress.com/2009/10/20/typeclassopedia-in-japanese/ 23. http://chplib.wordpress.com/2009/10/19/an-early-look-at-threadscope/ 24. http://www.mega-nerd.com/erikd/Blog/FP-Syd/fp-syd-19.html 25. http://blog.snoyman.com/2009/10/19/monadic-pairs-and-kleisli-arrows/ 26. http://martijn.van.steenbergen.nl/journal/2009/10/18/transforming-polymorph… 27. http://justtesting.org/post/216085196 28. http://donsbot.wordpress.com/2009/10/17/multicore-haskell-now-acm-reflectio… 29. http://blog.sigfpe.com/2009/10/what-category-do-haskell-types-and.html 30. http://justtesting.org/post/215438784 31. http://www.haskell.org/mailman/listinfo/haskell 32. http://sequence.complete.org/ 33. http://planet.haskell.org/ 34. http://sequence.complete.org/node/feed 35. http://haskell.org/ 36. http://haskell.org/haskellwiki/HWN 37. http://patch-tag.com/r/jfredett/HWN2/pullrepo%20HWN2 Hidden links: 38. http://www.galois.com/blog/2009/10/20/crenshaw-simplex/

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ANN: haskell-src-exts-1.2.0
by Niklas Broberg 23 Oct '09

23 Oct '09

Fellow Haskelleers, I'm pleased to announce the release of haskell-src-exts-1.2.0! * On hackage: http://hackage.haskell.org/package/haskell-src-exts * Via cabal: cabal install haskell-src-exts * Darcs repo: http://code.haskell.org/haskell-src-exts Version 1.2.0 is a new major release, following the PVP, as it contains a few backwards-incompatible changes, as well as some major changes that are supposedly backwards-compatible in theory, but as much of it is new and untested in practice there may be some regressions (bugs). The main new thing in 1.2.0 is the integration of the Annotated machinery into the package proper, for instance all parsing is now handled by the fully location-aware parser. haskell-src-exts-1.2.0: ==================== * Language.Haskell.Exts.Annotated.Simplify provides translation from an annotated AST to the old simple AST. * Behind-the-scenes integration of the new exact parser and lexer to do all parsing (using the above mentioned simplifier if the old AST version is requested). * All syntactic nodes now derive Eq, Ord and Show. * Pretty instance for SrcSpan. * Top-level expressions are now treated as implicit TH splice declarations (as per GHC HEAD). Note that this incurs a non-backwards-compatible change to the AST. * Empty data declarations may now have explicit kind annotations. * AST (and Pretty/Exact) support for kind variables (not yet parser support). * Error messages now extensively use prettyPrint instead of show for AST elements and locations, leading to way neater messages. * Bug fix to not crash ungracefully when encountering type equality predicates in proper types. * Liberalise line comments (as per GHC) to allow a line comment on the last line of a source file. Please help me test and report! Grab a darcs version, put your source files in the Test/examples dir, and go cabal test (in the top dir). Any failing cases not due to CPP or literate source files (for the exact-printer), please report to the trac: http://trac.haskell.org/haskell-src-exts Cheers, /Niklas

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ANN: quickcheck-poly - Automating QuickCheck for polymorphic/overloaded properties in a small world of types
by Ahn, Ki Yung 23 Oct '09

23 Oct '09

Often times QuickCheck properties are polymophic/overloaded without giving a monomorphic type signature. But there can be several types that you are interested. You can write scripts that check all the types you are interested annotating the generic property for each different monotype, which is a tedious work to do. Here, I automated this via hint (a Haskell Interpreter Library). How it works is it first asks a type of a property to the Haskell interpreter and gets a type string, identifies type variables that start with lowercase alphabet, generate all possible substitution that may or may not be a correct type, stick the type string to the property name as a signature and collect only the meaningful types, and then finally run quickCheck over each meaningful types. The example below clearly illustrates what it does. P.S. If there is a way to work this out without hint and string manipulation I would be happy to hear that. I've tried template haskell but didn't work since you cannot test whether given type is correct or instance of some class; it should be correct in the first place, no way to recover from failure of type checking. import Test.QuickCheck.PolyQC import Prop -- the module that defiens the properties p0, p1, p2, p3, p4 -- p0 x = x == x -- p1 x y z = x + (y + z) == (x + y) + z -- p2 x y = x + y == y + x -- p3 x = x == negate (negate x) -- p4 p = (fst p, snd p) == p main = do putStrLn "testing p0 =======================================" print =<< polyQuickCheck' "Prop" "p0" ["Bool","Int","Double"] putStrLn "testing p1 =======================================" print =<< polyQuickCheck' "Prop" "p1" ["Bool","Int","Double"] putStrLn "testing p2 =======================================" print =<< polyQuickCheck' "Prop" "p2" ["Bool","Int","Double"] putStrLn "testing p3 =======================================" print =<< polyQuickCheck' "Prop" "p3" ["Bool","Int","Double"] putStrLn "testing p4 =======================================" print =<< polyQuickCheck' "Prop" "p4" ["Bool","Int","Double"] return () {- *Main> :t p0 p0 :: (Eq a) => a -> Bool *Main> :t p1 p1 :: (Num a) => a -> a -> a -> Bool *Main> :t p2 p2 :: (Num a) => a -> a -> Bool *Main> :t p3 p3 :: (Num a) => a -> Bool *Main> :t p4 p4 :: (Eq a, Eq b) => (a, b) -> Bool *Main> main testing p0 ======================================= Right ["(\"(Eq Bool) => Bool -> Bool\",+++ OK, passed 100 tests. ())","(\"(Eq Int) => Int -> Bool\",+++ OK, passed 100 tests. ())","(\"(Eq Double) => Double -> Bool\",+++ OK, passed 100 tests. ())"] testing p1 ======================================= Right ["(\"(Num Int) => Int -> Int -> Int -> Bool\",+++ OK, passed 100 tests. ())","(\"(Num Double) => Double -> Double -> Double -> Bool\",*** Failed! Falsifiable (after 9 tests and 2 shrinks): 4.0 -26.0 8.777291602197652 ())"] testing p2 ======================================= Right ["(\"(Num Int) => Int -> Int -> Bool\",+++ OK, passed 100 tests. ())","(\"(Num Double) => Double -> Double -> Bool\",+++ OK, passed 100 tests. ())"] testing p3 ======================================= Right ["(\"(Num Int) => Int -> Bool\",+++ OK, passed 100 tests. ())","(\"(Num Double) => Double -> Bool\",+++ OK, passed 100 tests. ())"] testing p4 ======================================= Right ["(\"(Eq Bool, Eq Bool) => (Bool, Bool) -> Bool\",+++ OK, passed 100 tests. ())","(\"(Eq Bool, Eq Int) => (Bool, Int) -> Bool\",+++ OK, passed 100 tests. ())","(\"(Eq Bool, Eq Double) => (Bool, Double) -> Bool\",+++ OK, passed 100 tests. ())","(\"(Eq Int, Eq Bool) => (Int, Bool) -> Bool\",+++ OK, passed 100 tests. ())","(\"(Eq Int, Eq Int) => (Int, Int) -> Bool\",+++ OK, passed 100 tests. ())","(\"(Eq Int, Eq Double) => (Int, Double) -> Bool\",+++ OK, passed 100 tests. ())","(\"(Eq Double, Eq Bool) => (Double, Bool) -> Bool\",+++ OK, passed 100 tests. ())","(\"(Eq Double, Eq Int) => (Double, Int) -> Bool\",+++ OK, passed 100 tests. ())","(\"(Eq Double, Eq Double) => (Double, Double) -> Bool\",+++ OK, passed 100 tests. ())"] -}

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2nd CFP: JSC Special Issue on Automated Verification and Specification of Web Systems
by demis＠dimi.uniud.it 22 Oct '09

22 Oct '09

[Apologies for multiple copies] ======================================================================== JOURNAL OF SYMBOLIC COMPUTATION Special Issue on Automated Specification and Verification of Web Systems http://www.risc.uni-linz.ac.at/people/tkutsia/jsc-wwv.html ======================================================================== SCOPE ----- This special issue is related to the topics of the workshop WWV'09: Automated Specification and Verification of Web Systems, which took place in Hagenberg, Austria, on July 17, 2009. Both participants of the workshop and other authors are invited to submit contributions. The increased complexity of Web sites and the explosive growth of Web-based applications has turned their design and construction into a challenging problem. Nowadays, many companies have diverted their Web sites into interactive, completely-automated, Web-based applications (such as Amazon, on-line banking, or travel agencies) with a high complexity that requires appropriate specification and verification techniques and tools. Systematic, formal approaches to the analysis and verification can address the problems of this particular domain with automated and reliable tools that also incorporate semantic aspects. We solicit original papers on symbolic methods and techniques applied to Web sites, Web services or Web-based applications, such as: * Rule-based approaches to Web systems analysis, certification, specification, verification, and optimization * Algebraic methods for verification and certification of Web systems * Formal models for describing and reasoning about Web systems * Model-checking, synthesis and debugging of Web systems * Abstract interpretation and program transformation applied to the semantic Web * Intelligent tutoring and advisory systems for Web specifications authoring * Web quality and Web metrics * Web usability and accessibility * Testing and evaluation of Web systems and applications * ... Submissions describing applications of algebraic methods and techniques are especially encouraged. SUBMISSION ---------- Submission details and requirements are available from the Web page: http://www.risc.uni-linz.ac.at/people/tkutsia/jsc-wwv.html IMPORTANT DATES --------------- * Submission of papers: November 23, 2009. * Notification of acceptance/rejection: March 22, 2010. GUEST EDITORS ------------ * Demis Ballis (University of Udine, Italy) * Temur Kutsia (RISC, Johannes Kepler University Linz, Austria)

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*** extended deadline: FLOPS 2010: Last Call for Papers ***
by Matthias Blume 20 Oct '09

20 Oct '09

---------------------------------------------------------------------------- LAST CALL FOR PAPERS Tenth International Symposium on Functional and Logic Programming (FLOPS 2010) April 19-21, 2010 Sendai, Japan http://www.kb.ecei.tohoku.ac.jp/flops2010/ ** EXTENDED SUBMISSION DEADLINES ** abstracts: October 27, 2009 papers: November 3, 2009 FLOPS is a forum for research on all issues concerning declarative programming, including functional programming and logic programming, and aims to promote cross-fertilization and integration between the two paradigms. Previous FLOPS meetings were held in Fuji Susono (1995), Shonan Village (1996), Kyoto (1998), Tsukuba (1999), Tokyo (2001), Aizu (2002), Nara (2004), Fuji Susono (2006), and Ise (2008). TOPICS FLOPS solicits original papers in all areas of functional and logic programming, including (but not limited to): Declarative Pearls: new and excellent declarative programs with illustrative applications. Language issues: language design and constructs, programming methodology, integration of paradigms, interfacing with other languages, type systems, constraints, concurrency and distributed computing. Foundations: logic and semantics, rewrite systems and narrowing, type theory, proof systems. Implementation issues: compilation techniques, memory management, program analysis and transformation, partial evaluation, parallelism. Applications: case studies, real-world applications, graphical user interfaces, Internet applications, XML, databases, formal methods and model checking. The proceedings will be published as an LNCS volume. The proceedings of the previous meeting (FLOPS 2008) were published as LNCS 4989. INVITED SPEAKERS TBD PC CO-CHAIRS Matthias Blume (Google, Chicago, USA) German Vidal (Technical University of Valencia, Spain) CONFERENCE CHAIR Naoki Kobayashi (Tohoku University, Sendai, Japan) PC MEMBERS Nick Benton (Microsoft Research, Cambridge, UK) Manuel Chakravarty (University of New South Wales, Australia) Michael Codish (Ben-Gurion University of the Negev, Israel) Bart Demoen (Katholieke Universiteit Leuven, Belgium) Agostino Dovier (University of Udine, Italy) John P. Gallagher (Roskilde University, Denmark) Maria Garcia de la Banda (Monash University, Australia) Michael Hanus (University of Kiel, Germany) Atsushi Igarashi (Kyoto University, Japan) Patricia Johann (Rutgers University, USA) Shin-ya Katsumata (Kyoto University, Japan) Michael Leuschel (University of Dusseldorf, Germany) Francisco Lopez-Fraguas (Complutense University of Madrid, Spain) Paqui Lucio (University of the Basque Country, Spain) Yasuhiko Minamide (University of Tsukuba, Japan) Frank Pfenning (Carnegie Mellon University, USA) Francois Pottier (INRIA, France) Tom Schrijvers (Katholieke Universiteit Leuven, Belgium) Chung-chieh "Ken" Shan (Rutgers University, USA) Zhong Shao (Yale University, USA) Jan-Georg Smaus (University of Freiburg, Germany) Nobuko Yoshida (Imperial College London, UK) LOCAL CHAIR Eijiro Sumii (Tohoku University, Sendai, Japan) SUBMISSION Submissions must be unpublished and not submitted for publication elsewhere. Work that already appeared in unpublished or informally published workshops proceedings may be submitted. Submissions should fall into one of the following categories: Regular research papers: they should describe new results and will be judged on originality, correctness, and significance. System descriptions: they should contain a link to a working system and will be judged on originality, usefulness, and design. All submissions must be written in English and can be up to 15 proceedings pages long. Authors are strongly encouraged to use LaTeX2e and the Springer llncs class file, available at http://www.springer.de/comp/lncs/authors.html Regular research papers should be supported by proofs and/or experimental results. In case of lack of space, this supporting information should be made accessible otherwise (e.g., a link to a web page, or an appendix). Papers should be submitted electronically at http://www.easychair.org/conferences/?conf=flops2010 IMPORTANT DATES Submission deadlines: - Abstract: October 27, 2009 - Paper: November 3, 2009 Author notification: December 21, 2009 Camera-ready copy: January 24, 2010 Conference: April 19-21, 2010 PLACE Sendai, Japan Some previous FLOPS: FLOPS 2008, Ise: http://www.math.nagoya-u.ac.jp/~garrigue/FLOPS2008/ FLOPS 2006, Fuji Susono: http://hagi.is.s.u-tokyo.ac.jp/FLOPS2006/ FLOPS 2004, Nara FLOPS 2002, Aizu: http://www.ipl.t.u-tokyo.ac.jp/FLOPS2002/ FLOPS 2001, Tokyo: http://www.ueda.info.waseda.ac.jp/flops2001/ SPONSOR Japan Society for Software Science and Technology (JSSST), SIG-PPL Graduate School of Information Sciences, Tohoku University International Information Science Foundation IN COOPERATION with AAFS (Asian Association for Foundation of Software) ACM SIGPLAN ALP (Association for Logic Programming) ----------------------------------------------------------------------------

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Haskell Weekly News: Issue 136 - October 17, 2009
by jfredett＠gmail.com 17 Oct '09

17 Oct '09

--------------------------------------------------------------------------- Haskell Weekly News http://sequence.complete.org/hwn/20091017 Issue 136 - October 17, 2009 --------------------------------------------------------------------------- Welcome to issue 136 of HWN, a newsletter covering developments in the [1]Haskell community. Over the last week, fpisfun from reddit announced a [2]new subreddit for simple, direct applications of Haskell to common problems which normally might be solved by a perl script or bit of bash. There are a number of examples already there, and the numbers keep growing. It's not just command-line utilities either, there is also [3]this post on calculating the bend needed for a bay window curtainrod. There is plenty of great material if you're new to Haskell and looking for some basic examples of different simple projects, examples of using monads and functors appropriately, or just want to see some 'real' programs in Haskell, it's worth a look! Also, a small correction, due to some issues with the tools, unicode characters get replaced with their ASCII 'equivalents' so that an 'e' with an umlaut becomes an 'e' character. Thanks to Wolfram Kahl for pointing out that this change is not as innocent as I thought, apologies thusly to Guenther Schmidt (I'm told thats a better approximation of the correct spelling) for the error, I apologize in advance for any other similar errors. I'm working on improving the unicode support in the tools, but it's a nasty bug to catch. This was a long editorial, so I won't take any more of your time, Haskellers, the Haskell Weekly News! Announcements Call for Contributions - Haskell Communities and Activities Report, November 2009 edition. voigt [4]called for contributions to the November 2009 issue of the Haskell Communities and Activities Report. See post for details. Call for Participation: VSTTE 2009. Jean-Christophe Filliatre [5]announced a call for participation for the VSTTE Workshop. WFLP 2010 Call for papers. Pablo Nogueira [6]announced a call for papers for the 2010 WFLP. BAHUG Next meeting: October 21st at MIT (32G-882). Ravi Nanavati [7]announced the next meeting of the Boston Area Haskell User's Group. Which will be in the CSAIL Reading Room at MIT. This editor hopes to actually make it to this one, so maybe I'll see you there! fp-southwales, the South Wales Functional Programming User Group. Andy Gimblett [8]announced the formation of fp-southwales, a user group for anybody interested in functional programming in the area of south Wales, UK. The Monad.Reader (14) - Call for copy. Brent Yorgey [9]announced the call for copy for the next issue of `The Monad.Reader`, Issue #14 Extensions to Vec uploaded (useful for GPipe programs). Tobias Bexelius [10]announced two extensions to the Vec package: Vec-Transform and Vec-Boolean. Vec-Transform provides some 4x4 transform matrices such as perspective projection and rotation. Vec-Boolean provides Data.Boolan instances for the Vec data types. Bindings to FFMpeg library. Vasyl Pasternak [11]announced the next release of the hs-ffmpeg library. Downloadable from Hackage along with the ffmpeg-tutorials, which show capabilities of this library. The installation process is a bit tricky so Vasyl put up a [12]blog post which describes the installation process. Haskell Hackathon in Zurich, Switzerland. Johan Tibell [13]announced a Hackathon in Zurich, to be held in March in the Google office. No concrete date has been decided, but if your interested, make sure to add your name [14]here. Reverse Dependencies in Hackage (demo). Roel van Dijk [15]announced his patch to add reverse-dependencies to Hackage, see the linked post for information on where to see an example version of hackage. Discussion Relational Algebra. Guenther Schmidt [16]asked about whether or not a EDSL for relational algebra in Haskell. GHC devs. Andrew Coppin [17]asked about how many GHC Developers there are, and was somewhat surprised with the answer. Fuzzy Logic / Linguistic Variables. Neal Alexander [18]demonstrated an implementation of fuzzy logic taken from the book: 'Programming Game AI by Example' by Mat Buckland. In the book, the code was in C++, rewriting it in Haskell made for much more succint, readable code. Graph Library Using Associated Types. Lajos Nagy [19]asked about using Associated types in a Graph library. Is proof by testing possible? Muad'Dib [20]asked us Haskell Mentat's about whether it was possible to prove a function correct in a finite number of tests. The discussion brought forth not only answers but some /very cool/ results about the application of compactness (in the topological sense) to testing. Blog noise [21]Haskell news from the [22]blogosphere. Blog posts from people new to the Haskell community are marked with >>>, be sure to welcome them! * Don Stewart (dons): [23]LACSS 2009: Domain Specific Languages and Haskell. * FP Lunch: [24]Factorising folds for faster functions. * Mikael Vejdemo Johansson (Syzygy-): [25][MATH 198] Lecture 4 and a question for the community. More of Syzygy's lectures on category theory, Syzygy also asks about what it means to 'integrate' a datatype. * Neil Brown: [26]Emulating Shared Mutable Variables with Message-Passing Processes. * Galois, Inc: [27]Tech Talk: Writing Linux Kernel Modules with Haskell. * Galois, Inc: [28]Domain Specific Languages for Domain Specific Problems. * FP-Syd: [29]Sydney FP Group: FP-Syd #18.. * Neil Brown: [30]The octopus, the boids and GHC 6.12.1rc1. * Brent Yorgey: [31]Call for submissions: Monad.Reader issue 15. * Brent Yorgey: [32]diagrams 0.2.1, and future plans. * Don Stewart (dons): [33]Self-optimizing data structures: using types to make lists faster. * Martijn van Steenbergen: [34]Context Synonyms. * Joachim Breitner: [35]arbtt: Now with Documentation. * Dan Piponi (sigfpe): [36]Vectors, Invariance, and Math APIs. * Creighton Hogg: [37]How to teach Category Theory?. Quotes of the Week * sproingie: How do you beta-reduce a problem like Maria * Baughn: There's also the language, Quine, whose interpreter is implemented as a symlink to /bin/cat * benmachine: [on the best editor] opinions vary. from correct opinions i.e. mine to other ones. [editor's comment: Obviously, this question is settled, the best editor is *garbled*] * pozic: statistics. a wonderful tool to control people. * FunctorSalad: I think the 'asks', 'gets' etc family of names is sort of cute, like the program is talking about itself in the third person * mmorrow:: Right, that's just beggin for a State monad. About the Haskell Weekly News New editions are posted to [38]the Haskell mailing list as well as to [39]the Haskell Sequence and [40]Planet Haskell. [41]RSS is also available, and headlines appear on [42]haskell.org. To help create new editions of this newsletter, please see the information on [43]how to contribute. Send stories to jfredett . at . gmail . dot . com. The darcs repository is available at darcs get [44]http://patch-tag.com/r/jfredett/HWN2/pullrepo HWN2 . References 1. http://haskell.org/ 2. http://www.reddit.com/r/EnHaskell 3. http://www.reddit.com/r/EnHaskell/comments/9syi3/calculating_the_bend_for_a… 4. http://article.gmane.org/gmane.comp.lang.haskell.general/17572 5. http://article.gmane.org/gmane.comp.lang.haskell.general/17570 6. http://article.gmane.org/gmane.comp.lang.haskell.cafe/64933 7. http://article.gmane.org/gmane.comp.lang.haskell.cafe/64928 8. http://article.gmane.org/gmane.comp.lang.haskell.cafe/64858 9. http://article.gmane.org/gmane.comp.lang.haskell.cafe/64717 10. http://article.gmane.org/gmane.comp.lang.haskell.cafe/64673 11. http://article.gmane.org/gmane.comp.lang.haskell.cafe/64901 12. http://progandprog.blogspot.com/2009/10/video-processing-on-haskell-easy.ht… 13. http://article.gmane.org/gmane.comp.lang.haskell.cafe/64947 14. http://haskell.org/haskellwiki/ZuriHac#Possible_Attendees 15. http://article.gmane.org/gmane.comp.lang.haskell.cafe/64915 16. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/64899 17. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/64867 18. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/64860 19. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/64812 20. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/64757 21. http://planet.haskell.org/ 22. http://haskell.org/haskellwiki/Blog_articles 23. http://donsbot.wordpress.com/2009/10/16/lacss-2009-domain-specific-language… 24. http://sneezy.cs.nott.ac.uk/fplunch/weblog/?p=267 25. http://blog.mikael.johanssons.org/archive/2009/10/math-198-lecture-4-and-a-… 26. http://chplib.wordpress.com/2009/10/14/emulating-shared-mutable-variables-w… 27. http://www.galois.com/blog/2009/10/13/haskellkernelmodules/ 28. http://www.galois.com/blog/2009/10/13/domain-specific-languages-for-domain-… 29. http://www.mega-nerd.com/erikd/Blog/FP-Syd/fp-syd-18.html 30. http://chplib.wordpress.com/2009/10/12/the-octopus-the-boids-and-ghc-6-12-1… 31. http://byorgey.wordpress.com/2009/10/12/call-for-submissions-monad-reader-i… 32. http://byorgey.wordpress.com/2009/09/24/diagrams-0-2-1-and-future-plans/ 33. http://donsbot.wordpress.com/2009/10/11/self-optimizing-data-structures-usi… 34. http://martijn.van.steenbergen.nl/journal/2009/10/11/context-synonyms/ 35. https://www.joachim-breitner.de/blog/archives/342-arbtt-Now-with-Documentat… 36. http://blog.sigfpe.com/2009/10/vectors-invariance-and-math-apis.html 37. http://abstractabsurd.blogspot.com/2009/10/how-to-teach-category-theory.html 38. http://www.haskell.org/mailman/listinfo/haskell 39. http://sequence.complete.org/ 40. http://planet.haskell.org/ 41. http://sequence.complete.org/node/feed 42. http://haskell.org/ 43. http://haskell.org/haskellwiki/HWN 44. http://patch-tag.com/r/jfredett/HWN2/pullrepo%20HWN2

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ANNOUNCE IDynamic-0.1
by Alberto G. Corona 16 Oct '09

16 Oct '09

IDynamic is variant of Data.Dynamic that can be indexed, serialized., stored, transmitted trough communications etc. So it can be used in abstract data containers, persistence, communications etc. http://hackage.haskell.org/package/IDynamic I Just uploaded it, so the documentation has not been created by Hackage. However I uincluded an example in the pachage. {-# OPTIONS -XTypeSynonymInstances #-} module Main where import Data.IResource import Data.IDynamic import Data.Typeable instance IResource Int where keyResource x= "I" serialize = show deserialize = read defPath _= "saved/" instance IResource String where keyResource x= take 5 x serialize = show deserialize = read defPath _= "saved/" main= do putStrLn "see the code to know the meaning of he results" registerType :: IO Int -- register both datatypes (Int, and String) registerType :: IO String let x= 1 :: Int let list= [IDynamic x, IDynamic "hello, how are you"] --typical Dynamic usage let assoc= zip (map keyResource list) list print $ lookup (keyResource (5 ::Int)) assoc -- lookup a IDynamic object from a container and show it mapM writeResource list mds ← readResource $ IDynamic "hello" -- save both objects case mds of Nothing → error "must have been Just!" --why? Just ds → do putStrLn $ serialize ds -- serialize the dynamic object and print it let str= fromIDyn ds :: String -- casting putStrLn str -- print the string read let y= fromIDyn ds :: Int -- casting error print y

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ANN: Haskell Hackathon in Zurich, Switzerland
by Johan Tibell 16 Oct '09

16 Oct '09

Hi all! We are in the early stages of planning a Haskell hackathon/get together, ZuriHac, to be held this March at the Google office, in Zurich, Switzerland. Right now we're looking at four possible dates (Friday-Sunday): March 5-7, March 12-14, March 19-21, or March 26-28. If you might be interested in attending, please add your name on the wiki page: http://haskell.org/haskellwiki/ZuriHac#Possible_Attendees If you don't have an account on the wiki feel free to just respond to this email. If there are any dates that absolutely don't work for you then please note them on the wiki. I'll come back with a finalized date and more details soon. Hope to see you in Zurich! Johan Tibell (tibbe)

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