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ANN: hsmagick 0.5
by Vincent Gerard 13 Mar '11

13 Mar '11

Hello Haskellers, I am currently taking over the maintainership of hsmagick, a FFI bindings library to ImageMagick. Therefore, I am pleased to announce the 0.5 release of hsmagick. http://hackage.haskell.org/package/hsmagick Major changes: ------ * imageToBlob and blobToImage functions using ByteStrings * Use of ForeignPtr instead of Ptr as memory references representation. Thanks to Steffen Siering patches, the internal representation has been changed from Ptr to ForeignPtr. The finalization of ForeignPtr should resolve space leaks issues. * destroyImage function is exposed, to release the memory immediately. * hsmagick builds with GHC 7 The source repository is now hosted on github https://github.com/vincentg/hsmagick Please, do not hesitate to contact me by email or with github for any questions, requests, bugs, patches, anything about hsmagick. Cheers, Vincent Gerard (Please make sure not to reply to haskell(a)haskell.org.)

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Last CfP: WRS 2011 - 10th International Workshop on Reduction Strategies in Rewriting and Programming
by Santiago Escobar 11 Mar '11

11 Mar '11

Last Call for Papers WRS 2011 10th International Workshop on Reduction Strategies in Rewriting and Programming http://www.dsic.upv.es/workshops/wrs2011 29 May 2011, Novi Sad, Serbia An RDP 2011 workshop Federated Conference on Rewriting, Deduction, and Programming This workshop promotes research and collaboration in the area of reduction strategies. It encourages the presentation of new directions, developments, and results as well as surveys and tutorials on existing knowledge in this area. Reduction strategies define which (sub)expression(s) should be selected for evaluation and which rule(s) should be applied. These choices affect fundamental properties of computations such as laziness, strictness, completeness, and efficiency, to name a few. For this reason programming languages such as Elan, Maude, OBJ, Stratego, and TOM allow the explicit definition of the evaluation strategy, whereas languages such as Clean, Curry, and Haskell allow its modification. In addition to strategies in rewriting and programming, WRS also covers the use of strategies and tactics in other areas such as theorem and termination proving. Previous editions of the workshop were held in Utrecht (2001), Copenhagen (2002), Valencia (2003), Aachen (2004), Nara (2005), Seattle (2006), Paris (2007), Hagenberg (2008), Brasilia (2009), and Edinburgh (2010); the last one as a joint workshop with the STRATEGIES workshop. Further information can be found at the permanent site for WRS <http://www.dsic.upv.es/~wrs/>. WRS 2011 is planned to be co-located with RTA 2011 (22nd International Conference on Rewriting Techniques and Applications), as a satellite event of RDP, the Federated Conference on Rewriting, Deduction, and Programming. WRS 2011 will be held at Novi Sad, Serbia on 29 May 2011. Submissions and Publication: Before the workshop, authors are invited to submit an extended abstract (max. 5 pages) to be formatted in the EasyChair class style through the EasyChair submission site. Accepted abstracts will be presented at the workshop and included in the preliminary proceedings, available at the workshop. After the workshop, authors will be invited to submit a full paper of their presentation (typically a 15-pages paper), which will be refereed and considered for publication in an electronic journal, such as Electronic Proceedings in Theoretical Computer Science. Beyond original ideas and recent results not published nor submitted elsewhere, we also invite authors to submit a 5-pages abstract describing relevant work that has been or will be published elsewhere, or work in progress. These submissions will be only considered for presentation at the workshop and inclusion in the preliminary proceedings but not in the final proceedings. We envisage publication of a special issue of a journal dedicated to WRS after the event. Important Dates: # Submission: 20 March 2011 # Notification: 4 April 2011 # Preliminary proceedings version due: 15 April 2011 # Workshop: 29 May 2011 # Submission for final proceedings: 12 September 2011 # Notification: 7 November 2011 # Final version: 21 November 2011 Programme Committee: # Dan Dougherty, Worcester Polytechnic Institute, USA # Santiago Escobar, Universidad Politecnica de Valencia, Spain (chair) # Maribel Fernandez, King's College London, UK # Juergen Giesl, RWTH Aachen, Germany # Bernhard Gramlich, Technische Universit Wien, Austria # Helene Kirchner, Centre de Recherche INRIA Bordeaux, France # Francisco Javier Lopez Fraguas, Universidad Complutense de Madrid, Spain # Salvador Lucas, Universidad Politecnica de Valencia, Spain # Aart Middeldorp, University of Innsbruck, Austria # Jaco van de Pol, University of Twente, The Netherlands # Masahiko Sakai, Nagoya University, Japan # Manfred Schmidt-Schauss, Johann Wolfgang Goethe-Universitat, Germany For more information, please contact Santiago Escobar Universidad Politecnica de Valencia, Spain Email: sescobar(a)dsic.upv.es

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ANN: Updates in the monadic regions family
by Bas van Dijk 10 Mar '11

10 Mar '11

Dear all, I released new versions of some of my packages. Here are the changelogs: http://hackage.haskell.org/package/regions-0.9 http://hackage.haskell.org/package/regions-mtl-0.3.1.5 http://hackage.haskell.org/package/regions-monadstf-0.3.1.5 * Switch from monad-peel to monad-control. * Removed Control.Monad.Trans.Region.Concurrent. The fork functions contained bugs which could not be fixed. I'm working on a way to copy handles from one thread to another but the design has not settled yet. * Removed Data.RegionRef. I always considered this module a bit of a wart. * Added support for local regions. Primarily needed for the alloca functions from the regional-pointers package. More on that below. http://hackage.haskell.org/package/regional-pointers-0.6 * Switch from monad-peel to monad-control. * Major API change: Use the new local regions. This means that instead of: alloca ∷ (Storable α, MonadPeelIO pr) ⇒ (∀ s. RegionalPtr α (RegionT s pr) → RegionT s pr β) → pr β I now have: alloca ∷ (Storable α, MonadControlIO pr) ⇒ (∀ sl. LocalPtr α (LocalRegion sl s) → RegionT (Local s) pr β) → RegionT s pr β This allows my alloca to use the native alloca which is more efficient than doing a manual malloc and free as I did before. The type also allows to open resources in the continuation and use them outside the continuation and visa versa. * Have separate types for the three different pointers: - RegionalPtr: for pointers created using malloc. - LocalPtr: for pointers created using alloca. - NullPtr: for the nullPtr. * Add the type classes Pointer and AllocatedPointer to classify them. http://hackage.haskell.org/package/safer-file-handles-0.10 http://hackage.haskell.org/package/safer-file-handles-bytestring-0.2 http://hackage.haskell.org/package/safer-file-handles-text-0.2 * Switch from monad-peel to monad-control. * Support regional-pointers-0.6 and use its overloaded pointers. * Add separate types for standard handles: StdFileHandle and normal handles: RegionalFileHandle. * Add the type class FileHandle to group them. * Overload the filehandle in operations. http://hackage.haskell.org/package/usb-0.8 * getStrDesc and getStrDescFirstLang now return a Text instead of a String. This is a more efficient and cleaner interface. http://hackage.haskell.org/package/usb-enumerator-0.3 * Switch from monad-peel to monad-control. * Support iteratee-0.8.*. * Support usb-0.9. http://hackage.haskell.org/package/usb-safe-0.12 * Switched from monad-peel to monad-control. * Exported the ReadEndpoint, WriteEndpoint and EnumReadEndpoint type classes so you can refer to them in type signatures. * Support usb-0.8: getStrDesc and getStrDescFirstLang now return a Text instead of a String. * Support regions-0.9. * Support usb-enumerator-0.3. * Support iteratee-0.8.*. Regards, Bas

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Haskell Weekly News: Issue 172
by Daniel Santa Cruz 10 Mar '11

10 Mar '11

Welcome to issue 172 of the HWN, a newsletter covering developments in the [1]Haskell community. This release covers the week of February 27 to March 05, 2011. Announcements Jasper Van der Jeugt [2]announced the release of version 3 of Hakyll. He informs us that this is a complete re-write, and not backwards compatible. Horvath Zoltan [3]informed us about the 4th Central European Functional Programming School (CEFP 2011), which is to take place in Eotvos Lorand University, Budapest, Hungary, from June 14-24, 2011. "The invited lecturers are the most prominent researchers in the field in Europe, and they will present state-of-the-art functional programming techniques." Janis Voigtlander [4]issued a call for papers for the 20th International Workshop on Functional and (Constraint) Logic Programming (WFLP 2011) to be held in Odense, Denmark, on July 19, 2011. Michael Hanus [5]issued a call for papers for the 13th International ACM SIGPLAN Symposium on Principles and Practice of Declarative Programming (PPDP 2011) to be held in Odense, Denmark, on July 20-22, 2011. Trystan Spangler [6]released a new version (0.3.0) of hspec, with "improvements including fixing a base dependency problem, and better reporting of failed examples." Magnus Therming [7]released new versions of dataenc (0.14), and omnicodec (0.5). "It contains a large change to the API. The old, rather simplistic, lazy API has been removed. It has been replaced by an API based on incremental encoding/decoding. This should make the library easier to use together with left-fold enumerators..." Rogan Creswick [8]announced that cabal-dev 0.7.4.0 has been uploaded to hackage. "We strongly suggest that everyone upgrade to this release, since this release specifically addresses changes in Cabal-1.10 and newer, which the latest cabal-install new uses." Frederick Ross [9]announced a minor upgrade to haskell-pgm (0.1.2), with a minor upgrade to the library to make it work with GHC 7. Uwe Schmidt [10]announced an update to hxt to version 9.1. Eric Kow [11]announced that the date and venue for the sixth Darcs Hacking sprint has been confirmed for Paris, April 1-3, 2011. Ian Lynagh and the GHC Team [12]announced a new patchlevel release of GHC. "This release contains a number of bugfixes relative to 7.0.1, so we recommend upgrading." Denis Bueno [13]announced new releases of funsat (0.6.2) and bitset (1.1). Michal Konecny [14]announced version 0.3.2 of hmpfr, bindings to the MPFR arbitrary precision floating point arithmetic library. "The changes in this version are quite small but significant." Jonathan Daugherty [15]announced version 1.0 of the vty-ui terminal user interface library. "The vty-ui library is a complete interactive user interface development toolkit for terminal applications." Jason Dusek [16]announced his now bash-0.0.0, which has "types and functions for generation of Bash scripts, with safe escaping and composition of large subsets of Bash statements and expressions." Quotes of the Week * lpsmith: I didn't take the time to figure out what should be done in finite cases. * <companion_cube> edwardk, you mean it's 2 phD/nick in average ? :) <edwardk> clearly this is why SPJ stays away, he doesn't want to dilute that metric. * edwardk: Haskell 98 is a laudable goal. * douglas-adams: I love deadlines, I especially like the swooshing sound they make as they fly past * kmc: the way to convert imperative code to functional is to think about what your code actually means, and then throw out most of the irrelevant details that imperative programming has forced on you * MonadsSuck: man, I hate it when an adjoint pair of functors get together and compose. So damn annoying * bwright: I don't get it everyone keeps telling me java is a safe language but it melted the plastic on my eeepc900 * danka: you could be a monadic vampire. I hear they bleed semicolons. Top Reddit Stories * ANNOUNCE: GHC version 7.0.2: From (haskell.org) scored 46 with comments. Read on [17]reddit or the [18]original post. * Greenfield Haskell: From (self.haskell), scored 36 with 188 comments. Read on [19]reddit or the [20]original post. * Patches for monad comprehensions are in and will be in the upcoming GHC 7.2 release: From (hackage.haskell.org) scored 34 with 15 comments. Read on [21]reddit or the [22]original post. * GHC 7.0.2 released!: From (haskell.org) scored 32 with 10 comments. Read on [23]reddit or the [24]original post. * Haskell on Android: From (self.haskell), scored 31 with 22 comments. Read on [25]reddit or the [26]original post. * Do you think Haskell will ever catch on?: From (self.haskell), scored 26 with 63 comments. Read on [27]reddit or the [28]original post. * hakyll 3.0 released (static site generator): From (jaspervdj.be), scored 25 with 1 comments. Read on [29]reddit or the [30]original post. * New release of cabal-dev: sandboxed, reproducible build environments for Haskell: From (haskell.org) scored 24 with 9 comments. Read on [31]reddit or the [32]original post. * News on Well-Typed, the Parallel GHC Project, and Eric Kow joins the team.: From (well-typed.com) scored 22 with 3 comments. Read on [33]reddit or the [34]original post. * Build Yourself a Bluetooth Controlled Six-Legged Robot : A Neighborhood of Infinity: From (blog.sigfpe.com) scored 21 with comments. Read on [35]reddit or the [36]original post. Top StackOverflow Answers * [37]Goto in Haskell: Can anyone explain this seemingly insane effect of continuation monad usage? votes: 14 Here's a somewhat informal answer, but hopefully useful. getCC' returns a continuation to the current point of execution; you can think of it as saving a stack frame. The continuation returned by getCC' has not only ContT's state at the point of the call, but also the state of any monad above ContT on the stack. When you restore that state by calling the ... * [38]How do Haskell compilers decide whether to allocate on the heap or the stack? votes: 13 When you call a function like this f 42 (g x y) then the runtime behaviour is something like the following: p1 = malloc(2 * sizeof(Word)) p1[0] = &Tag_for_Int p1[1] = 42 p2 = malloc(3 * sizeof(Word)) p2[0] = &Code_for_g_x_y p2[1] = x p2[2] = y f(p1, p2) That is, arguments are usually passed as pointers to objects on the heap like in Java, but ... * [39]Quick question about Arrow operators votes: 11 (***) :: (Arrow a) => a b c -> a b' c' -> a (b, b') (c, c') So specialize a to -> and we get: (***) :: (Arrow a) => (b -> c) -> (b' -> c') -> (b, b') -> (c, c') And that's great, except we want to, for whatever reason, take the first two arguments as a single pair instead. But that's easy, we just uncurry. Prelude ... * [40]QuickCheck: defining Arbitrary instance in terms of other Arbitraries votes: 9 I'd do it like this: instance Arbitrary C where arbitrary = do a <- arbitrary b <- arbitrary return (C a b) Although sclv's idea of using liftM2 from Control.Monad is probably better: instance Arbitrary C where arbitrary = liftM2 C arbitrary arbitrary Top StackOverflow Questions * Running a Haskell program on the Android OS (votes: 21, answers: 1) [41]read * Goto in Haskell: Can anyone explain this seemingly insane effect of continuation monad usage? (votes: 18, answers: 2) [42]read * Proving equality of streams (votes: 15, answers: 1) [43]read * Rotate the first argument to a function to become nth (votes: 12, answers: 7) [44]read * How do Haskell compilers decide whether to allocate on the heap or the stack? (votes: 9, answers: 2) [45]read About the Haskell Weekly News To help create new editions of this newsletter, please send stories to dstcruz(a)gmail.com. I'm in dire need of finding good "quotes of the week". If you happen to come across any, please don't hesitate to send it along. Until next time, Daniel Santa Cruz References 1. http://haskell.org/ 2. http://article.gmane.org/gmane.comp.lang.haskell.hakyll/128 3. http://article.gmane.org/gmane.comp.lang.haskell.general/18527 4. http://article.gmane.org/gmane.comp.lang.haskell.general/18528 5. http://article.gmane.org/gmane.comp.lang.haskell.general/18530 6. http://article.gmane.org/gmane.comp.lang.haskell.general/18533 7. http://article.gmane.org/gmane.comp.lang.haskell.libraries/15426 8. http://article.gmane.org/gmane.comp.lang.haskell.cafe/86897 9. http://article.gmane.org/gmane.comp.lang.haskell.general/18542 10. http://article.gmane.org/gmane.comp.lang.haskell.cafe/86922 11. http://article.gmane.org/gmane.comp.version-control.darcs.user/25916 12. http://article.gmane.org/gmane.comp.lang.haskell.general/18535 13. http://article.gmane.org/gmane.comp.lang.haskell.cafe/86937 14. http://article.gmane.org/gmane.comp.lang.haskell.cafe/86882 15. http://article.gmane.org/gmane.comp.lang.haskell.general/18540 16. http://article.gmane.org/gmane.comp.lang.haskell.cafe/86975 17. http://www.reddit.com/r/haskell/comments/fwk78/announce_ghc_version_702/ 18. http://www.haskell.org/pipermail/haskell/2011-March/022610.html 19. http://www.reddit.com/r/haskell/comments/fvabx/greenfield_haskell/ 20. file://localhost/r/haskell/comments/fvabx/greenfield_haskell/ 21. http://www.reddit.com/r/haskell/comments/fxjcl/patches_for_monad_comprehens… 22. http://hackage.haskell.org/trac/ghc/ticket/4370#comment:48 23. http://www.reddit.com/r/haskell/comments/fwkdh/ghc_702_released/ 24. http://www.haskell.org/ghc/download_ghc_7_0_2 25. http://www.reddit.com/r/haskell/comments/ful84/haskell_on_android/ 26. http://www.reddit.com/r/haskell/comments/ful84/haskell_on_android/ 27. http://www.reddit.com/r/haskell/comments/ftxc7/do_you_think_haskell_will_ev… 28. http://www.reddit.com/r/haskell/comments/ftxc7/do_you_think_haskell_will_ev… 29. http://www.reddit.com/r/haskell/comments/fusve/hakyll_30_released_static_si… 30. http://jaspervdj.be/hakyll/tutorial.html 31. http://www.reddit.com/r/haskell/comments/fx47b/new_release_of_cabaldev_sand… 32. http://www.haskell.org/pipermail/haskell-cafe/2011-March/089831.html 33. http://www.reddit.com/r/haskell/comments/fw311/news_on_welltyped_the_parall… 34. http://www.well-typed.com/blog/51 35. http://www.reddit.com/r/haskell/comments/ftxzx/build_yourself_a_bluetooth_c… 36. http://blog.sigfpe.com/2011/02/build-yourself-bluetooth-controlled-six.html 37. http://stackoverflow.com/questions/5193876/goto-in-haskell-can-anyone-expla… 38. http://stackoverflow.com/questions/5132350/how-do-haskell-compilers-decide-… 39. http://stackoverflow.com/questions/5200462/quick-question-about-arrow-opera… 40. http://stackoverflow.com/questions/5134259/quickcheck-defining-arbitrary-in… 41. http://stackoverflow.com/questions/5151858/running-a-haskell-program-on-the… 42. http://stackoverflow.com/questions/5193876/goto-in-haskell-can-anyone-expla… 43. http://stackoverflow.com/questions/5179821/proving-equality-of-streams 44. http://stackoverflow.com/questions/5188212/rotate-the-first-argument-to-a-f… 45. http://stackoverflow.com/questions/5132350/how-do-haskell-compilers-decide-…

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ANNOUNCE: cinvoke 0.1 released
by Remi Turk 09 Mar '11

09 Mar '11

I am happy to finally announce cinvoke 0.1, a binding to the C library cinvoke[1], allowing functions to be loaded and called whose names and types are not known before run-time. Why? Sometimes you can't use the Haskell foreign function interface because you parse the type of the function from somewhere else, i.e. you're writing an interpreter for a language that has an FFI itself. What? The main function it exports is: cinvoke :: Symbol -> RetType b -> [Arg] -> IO b And because code is worth a thousand words, here's a small program that uses libc to write a 1Gb buffer of random garbage to a file: > module Main where > > import Foreign.CInvoke > > main = do > cxt <- newContext > libc <- loadLibrary cxt "libc.so.6" > malloc <- loadSymbol libc "malloc" > creat <- loadSymbol libc "creat" > write <- loadSymbol libc "write" > free <- loadSymbol libc "free" > let sz = 2^30 > buf <- cinvoke malloc (retPtr retVoid) > [argCSize sz] > fd <- cinvoke creat retCInt [argString "/tmp/test", argCUInt 0o644] > n <- cinvoke write retCSize [argCInt fd, argPtr buf, argCSize sz] > cinvoke free (retPtr retVoid) [argPtr buf] It hopefully works on any machine on which cinvoke works, but has only been tested on linux x86_64. As the current version of cinvoke only installs a static library, it does not work from GHCi at the moment (without hacking cinvoke to build a shared library). More interesting examples are included in examples/ in the package. Where? Hackage: http://hackage.haskell.org/package/cinvoke Cheers, Remi [1] http://www.nongnu.org/cinvoke/

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Extended deadline: JAL Special Issue on Automated Specification and Verification of Web Systems
by Temur Kutsia 08 Mar '11

08 Mar '11

[Apologies for multiple copies] ======================================================================== JOURNAL OF APPLIED LOGIC Special Issue on Automated Specification and Verification of Web Systems http://www.risc.uni-linz.ac.at/people/tkutsia/jal-wwv.html DEADLINE EXTENSION ======================================================================== IMPORTANT DATES --------------- * Submission of papers: March 16, 2011 (extended). * Notification: June 6, 2011.

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Linker flags for foreign export.
by Jason Dusek 08 Mar '11

08 Mar '11

I am having no luck generating a foreign export and calling it from C. The problem seems to be that I must spoon feed the linker. My working example is the files under this directory on Github: https://github.com/solidsnack/bash/tree/106e4de8358a726984d54859fb0b4aeaf26… Running `make' to produce the executable that imports the binding yields a number of unresolved linkages: :; make import ghc --make -fPIC -dynamic -c exports.hs [1 of 1] Compiling LanguageBashExports ( exports.hs, exports.o ) ghc -shared exports.o exports_stub.o -o exports.so \ -L/usr/lib/ghc-6.12.1/ -lHSrts \ -L/usr/lib/ghc-6.12.1/ghc-prim-0.2.0.0/ -lHSghc-prim-0.2.0.0 \ -L/usr/lib/ghc-6.12.1/integer-gmp-0.2.0.0/ -lHSinteger-gmp-0.2.0.0 \ -L/usr/lib/ghc-6.12.1/base-4.2.0.0/ -lHSbase-4.2.0.0 \ -lffi gcc -g -Wall -O2 -fPIC -Wall -o import \ -I/usr/lib/ghc-6.12.1/include/ \ import.c exports.so exports.so: undefined reference to `timer_settime' exports.so: undefined reference to `__stginit_base_DataziWord_dyn' exports.so: undefined reference to `clock_gettime' exports.so: undefined reference to `__stginit_base_Prelude_dyn' exports.so: undefined reference to `__stginit_base_ForeignziCziTypes_dyn' exports.so: undefined reference to `timer_delete' exports.so: undefined reference to `timer_create' exports.so: undefined reference to `hs_free_stable_ptr' collect2: ld returned 1 exit status make: *** [import] Error 1 If I add linker directives for libHSrts and librt to the compilation of import.c, the only unresolved symbols remaining are the STG init functions for the Prelude, Data.Word and Foreign.C.Types: :; make import gcc -g -Wall -O2 -fPIC -Wall -o import \ -I/usr/lib/ghc-6.12.1/include/ \ import.c exports.so \ -L/usr/lib/ghc-6.12.1/ -lHSrts \ -lrt exports.so: undefined reference to `__stginit_base_DataziWord_dyn' exports.so: undefined reference to `__stginit_base_Prelude_dyn' exports.so: undefined reference to `__stginit_base_ForeignziCziTypes_dyn' collect2: ld returned 1 exit status make: *** [import] Error 1 This "hide and go seek" with symbols really makes me feel like I'm just doing it wrong, though. I linked exports.so statically so why shouldn't it include `hs_free_stable_ptr' already (as well as the stginit functions)? Not sure why I need to mention librt at this step and not at the previous one. The truth is, I don't write C very often and in fact I am only doing this to create a bridge to Ruby. How should I be approaching this? Is there an "SO-chasing" option? -- Jason Dusek Linux User #510144 | http://counter.li.org/

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ANNOUNCE: hspec-0.3.0 (better reporting of failed examples)
by Trystan Spangler 08 Mar '11

08 Mar '11

hspec version 0.3.0, Behavior Driven Development for Haskell, is now available! Improvements include fixing a base dependancy problem and better reporting of failed examples. Much thanks to Greg Weber for fixes and ideas! http://hackage.haskell.org/package/hspec https://github.com/trystan/hspec As always, any advice, comments, or questions are welcome, Trystan Spangler For those who would like to see an example, running this program: > import Test.Hspec > import Test.Hspec.HUnit > import Test.Hspec.QuickCheck (property) > import Test.HUnit (assertBool, assertEqual) > > main = hspec specs > > specs = describe "hspec 0.3.0" [ > it "still allows a Bool expression to act as an example" > (replicate 5 1 == [1,1,1,1,1]), > > it "still allows HUnit assertions to act as examples" > (assertBool "lame example" True), > > it "still allows QuickCheck properties to act as examples" > (property $ \ i -> (i::Int) == i + 1 - 1), > > it "now shows a list of failed examples" > (undefined :: Bool), -- expected to fail > > it "now collects better data from failed HUnit examples" > (assertEqual "this should fail" 1 2), -- expected to fail > > it "now collects better data from failed QuickCheck examples" > (property $ \ i -> (i::Int) * 2 - 2 /= i) -- expected to fail > ] should send this to stdout: hspec 0.3.0 - still allows a Bool expression to act as an example - still allows HUnit assertions to act as examples - still allows QuickCheck properties to act as examples x now shows a list of failed examples [1] x now collects better data from failed HUnit examples [2] x now collects better data from failed QuickCheck examples [3] 1) hspec 0.3.0 now shows a list of failed examples FAILED Prelude.undefined 2) hspec 0.3.0 now collects better data from failed HUnit examples FAILED this should fail expected: 1 but got: 2 3) hspec 0.3.0 now collects better data from failed QuickCheck examples FAILED *** Failed! Falsifiable (after 4 tests): 2 Finished in 0.0494 seconds 6 examples, 3 failures

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GPCE 2011 Call for Papers
by Chang Hwan Peter Kim 05 Mar '11

05 Mar '11

------------------------------------------------------------------------ CALL FOR PAPERS Tenth International Conference on Generative Programming and Component Engineering (GPCE 2011) October 22-23, 2011 Portland, Oregon, USA (collocated with SPLASH 2011) http://www.gpce.org http://www.facebook.com/GPCEConference http://twitter.com/GPCECONF LinkedIn: GPCE (http://tinyurl.com/48eoovb) ------------------------------------------------------------------------ IMPORTANT DATES * Submission of abstracts: Monday, May 16, 2011 * Submission of papers: Sunday, May 22, 2011 * Paper notification: Wednesday, July 6, 2011 * Submission of tech talks: Sunday, August 7, 2011 SCOPE Generative and component approaches are revolutionizing software development just as automation and componentization revolutionized manufacturing. Key technologies for automating program development are Generative Programming for program synthesis, Component Engineering for modularity, and Domain-Specific Languages (DSLs) for compact problem-oriented programming notations. The International Conference on Generative Programming and Component Engineering is a venue for researchers and practitioners interested in techniques that use program generation and component deployment to increase programmer productivity, improve software quality, and shorten the time-to-market of software products. In addition to exploring cutting-edge techniques of generative and component-based software, our goal is to foster further cross-fertilization between the software engineering and the programming languages research communities. SUBMISSIONS Research papers: 10 pages in SIGPLAN proceedings style (sigplanconf.cls, see http://www.sigplan.org/authorInformation.htm) reporting original and unpublished results of theoretical, empirical, conceptual, or experimental research that contribute to scientific knowledge in the areas listed below (the PC chair can advise on appropriateness). Tool demonstrations: Tool demonstrations should present tools that implement generative and component-based software engineering techniques, and are available for use. Any of the GPCE'11 topics of interest are appropriate areas for tool demonstrations. Purely commercial tool demonstrations will not be accepted. Submissions should contain a tool description of up to 6 pages in SIGPLAN proceedings style (sigplanconf.cls) and a demonstration outline of up to 2 pages text plus 2 pages screen shots. The six page description will, if the demonstration is accepted, be published in the proceedings. The 2+2 page demonstration outline will only be used by the PC for evaluating the submission. Workshops and tech talks: Workshops are organized by SPLASH - see the SPLASH website for details (http://splashcon.org) Tech talks are organized by GPCE as one or two talks at the end of each day of the conference. The talks will be about an hour in length and, similarly to tutorials, do not (need to) present original new research material. Unlike longer tutorials, these talks cannot be very interactive, and should instead aim to be 'keynote' style presentations. Please see the tech talks call for contributions at www.gpce.org for details. TOPICS GPCE seeks contributions in software engineering and in programming languages related (but not limited) to: * Generative programming o Reuse, meta-programming, partial evaluation, multi-stage and multi-level languages, step-wise refinement, generic programming, automated code generation o Semantics, type systems, symbolic computation, linking and explicit substitution, in-lining and macros, templates, program transformation o Runtime code generation, compilation, active libraries, synthesis from specifications, development methods, generation of non-code artifacts, formal methods, reflection * Generative techniques for o Product-line architectures o Distributed, real-time and embedded systems o Model-driven development and architecture o Resource bounded/safety critical systems. * Component-based software engineering o Reuse, distributed platforms and middleware, distributed systems, evolution, patterns, development methods, deployment and configuration techniques, formal methods * Integration of generative and component-based approaches * Domain engineering and domain analysis o Domain-specific languages including visual and UML-based DSLs * Separation of concerns o Aspect-oriented and feature-oriented programming, o Intentional programming and multi-dimensional separation of concerns * Applications of the above in industrial scenarios or to real-world problems, bridging the gap between theory and practice * Empirical studies o Original work in any of the areas above where there is a substantial empirical dimension to the work being presented. Such contributions might take the form of a case/field study, comparative analysis, controlled experiment, survey or meta-analysis of previous studies. Incremental improvements over previously published work should have been evaluated through systematic, comparative, empirical, or experimental evaluation. Submissions must adhere to SIGPLAN's republication policy (http://www.sigplan.org/republicationpolicy.htm) Please contact the program chair if you have any questions about how this policy applies to your paper (chairs(a)gpce.org) ORGANIZATION Chairs (chairs(a)gpce.org) General Chair: Ewen Denney (SGT/NASA Ames, USA) Program Chair: Ulrik Pagh Schultz (Univ. of Southern Denmark, Denmark) Publicity Chair: Chang Hwan Peter Kim (Univ. of Texas at Austin, USA) Program Committee * Andrzej Wasowski (IT University of Copenhagen, Denmark) * Aniruddha Gokhale (Vanderbilt University, USA) * Bernd Fischer (University of Southampton, UK) * Bruno C. d. S. Oliveira (Seoul National University, Korea) * Christian Kaestner (Philipps Universitat Marburg, Germany) * Chung-Chieh Shan (Rutgers, The State University of New Jersey, USA) * Don Batory (University of Texas at Austin, USA) * Eli Tilevich (Virginia Tech, USA) * Eric Tanter (University of Chile, Chile) * Gorel Hedin (Lund Institute of Technology, Sweden) * Ina Schaefer (TU Braunschweig, Germany) * Jeremiah Willcock (Indiana University, USA) * Jeremy Siek (University of Colorado at Boulder, USA) * Jurgen Vinju (Centrum Wiskunde en Informatica, The Netherlands) * Lionel Seinturier (University of Lille, France) * Marjan Mernik (University of Maribor, Slovenia) * Mat Marcus (Adobe Systems, USA) * Nicolas Loriant (INRIA, France) * Ras Bodik (University of California at Berkeley, USA) * Robert Gluck (University of Copenhagen, Denmark) * Steffen Zschaler (King's College London, UK) * Tudor Girba (netstyle.ch, Switzerland) * Walter Binder (University of Lugano, Switzerland) * Yanhong A. Liu (State University of New York at Stony Brook, USA)

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ANNOUNCE: vty-ui 1.0 released
by Jonathan Daugherty 05 Mar '11

05 Mar '11

I'm pleased to announce the release of version 1.0 of the vty-ui terminal user interface library. The vty-ui library is a complete interactive user interface development toolkit for terminal applications. It provides a wide range of "widgets" and infrastructure for implementing them, along with event loop and event handling facilities and text attribute management. Some examples of functionality provided by the library include: * Box layout widgets * Checkboxes and radio buttons * Scrolling lists * A filesystem browser * Dialog boxes * Tables * Single-line text editing This release is a complete rewrite and is therefore incompatible with applications built with previous releases. However, many of the same concepts -- even types -- are present in the rewrite. The library comes with a collection of demonstration programs (built with the 'demos' cabal flag) and a comprehensive User's Manual in addition to the standard Haddock API documentation. Get it on hackage: http://hackage.haskell.org/package/vty-ui-1.0 Get the source: https://github.com/jtdaugherty/vty-ui Get the User's Manual: http://codevine.org/vty-ui/vty-ui-users-manual-1.0.pdf Enjoy! -- Jonathan Daugherty Software Engineer Galois, Inc.

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