January 2009 - Haskell

Re: [Haskell-cafe] Re: Hypothetical Haskell job in New York
by John Goerzen 08 Jan '09

08 Jan '09

On Thu, Jan 08, 2009 at 09:46:36PM +0100, Manlio Perillo wrote: > I'm speaking about servers, not clients. > > How much of pure Haskell internet servers are used in a production > environment, in the "open internet" (and not in restricted LANs)? Does that really matter? I tend to judge technology based on its merits for my work, not on who uses it. The fact that Google uses Python didn't impact my decision to start using it, and it also didn't impact my decision to start using Haskell. > How much traffic they handle? > How hard are to maintain/update/develope/? Those, of course, are pretty good questions. > Personally, I only know http://hpaste.org/, based on > Server: HAppS/0.8.4 Take a look at Hackage. There are quite a few other Haskell web frameworks as well: everything from the low-level FastCGI to higher-level HSP and WASH. > And about HAppS, I'm not an Haskell expert, but reading the source I see > that static files are server (in the HTTP server) using > Data.ByteString.Lazy's hGetContents > > Is this ok? In what respect? The fact that something uses ByteString.Lazy.hGetContents doesn't imply a problem to me. It's a useful function. It can be used properly, or not, just as while or read() in C can be. It's not evil incarnate like sprintf() or anything :-) -- John

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Re: [Haskell-cafe] Re: Hypothetical Haskell job in New York
by Don Stewart 08 Jan '09

08 Jan '09

manlio_perillo: > Tony Hannan ha scritto: > >Let me give you more information about this hypothetical job posting. > >Our company is a startup CDN > >(http://en.wikipedia.org/wiki/Content_Delivery_Network) about 3 years > >old and doing well. You would hythothetically be one of 7 programmer who > >write all the software involved in a CDN including http server, dns > >server, monitoring, load balancing, customer and operator user > >interface, etc. The pay depends on experience but is good. > > > > Isn't it better to use Erlang for the http and dns server ? > > I don't really like the syntax, but you have many things already > implemented. > Unfortunately Haskell is not yet ready for this task. > > http://eddie.sourceforge.net/what.html > http://yaws.hyber.org/ > Umm... http and dns? You're kidding right? Half of hackage.haskell.org is devoted to networking tasks. -- Don

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ICFP: Child care at conference
by Matthew Fluet (ICFP Publicity Chair) 07 Jan '09

07 Jan '09

Potential ICFP attendees: The ACM-SIGPLAN Executive Committee, which oversees and sponsors ICFP, is considering expanding its travel grants for event participants in need of child care assistance. (Such expansion would also apply to other major SIGPLAN-sponsored conferences, such as PLDI, POPL, OOPSLA.) The purpose of this message is to solicit feedback from potential attendees regarding the desirability for child care assistance and what forms of assistance be most appropriate. If child care assistance at ICFP (or other SIGPLAN events) is of interest to you, please contact me (at icfp.publicity(a)gmail.com -or- fluet(a)tti-c.org) with your comments. Some questions of particular interest: * What age groups of children are most appropriate to cover? * What types of costs might SIGPLAN cover to facilitate your participation in events? Sincerely, -Matthew Fluet (ICFP Publicity Chair)

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possible bug in pretty-1.0.1.0
by John MacFarlane 05 Jan '09

05 Jan '09

I noticed a difference in how "hang" works between pretty-1.0.0.0 and pretty-1.0.1.0. I think it's a bug. If this isn't the right place to report it, please let me know where I should. (Maintainer is listed as libraries(a)haskell.org, but that is a closed mailing list. Perhaps Cabal should include a report-bugs-at field?) John GHCi, version 6.8.3: http://www.haskell.org/ghc/ :? for help ... Prelude Text.PrettyPrint> putStrLn $ render $ hang (char '*') 4 (text "hi" $$ text "there") Loading package pretty-1.0.0.0 ... linking ... done. * hi there GHCi, version 6.10.1: http://www.haskell.org/ghc/ :? for help ... Prelude Text.PrettyPrint> putStrLn $ render $ hang (char '*') 4 (text "hi" $$ text "there") Loading package pretty-1.0.1.0 ... linking ... done. * hi there

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ANNOUNCE: cabal2doap 0.1
by Greg Heartsfield 05 Jan '09

05 Jan '09

I am pleased to announce a new tool for cabalized Haskell projects: Cabal2doap generates Description of a Project (DOAP) XML/RDF data representing a Haskell project. This should make it possible for semantic web project aggregation sites to find and index Haskell projects. The project is available through Hackage: http://hackage.haskell.org/cgi-bin/hackage-scripts/package/cabal2doap You can read a little more about it, and see a DOAP graph generated from a haskell project at this blog post: http://blog.gregheartsfield.com/2009/01/04/cabal2doap/ Thanks, Greg Heartsfield

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ANN: wxHaskell 0.11.1
by Jeremy O'Donoghue 04 Jan '09

04 Jan '09

The wxHaskell development team is pleased to announce the release of wxHaskell 0.11.1, a Haskell binding for the wxWidgets GUI library. The Haskell support is built on a reasonably complete C language binding, which could be used as the basis for wxWidgets support on other languages/platforms which do not have easy mechanisms for linking with C++ code. The main highlights of wxHaskell 0.11.1 are: - Support for XRC resource files, allowing GUI design using a visual tool. Note that this is currently not type safe, and programs will crash if a widget is not cast to the correct type on loading. - Support for wxWidgets 2.8.x. Support for wxWidgets 2.4.2 is now dropped and wxHaskell will not compile against versions of wxWidgets prior to 2.6. This means that exploratory development using GHCi is no longer possible. Workaround is to continue to use older wxHaskell versions. - Support for GHC 6.10 - Preliminary support for Cabal / Hackage The full list of changes is provided at the end of this mail. Binary packages are available from the wxHaskell download site at http://sourceforge.net/project/showfiles.php?group_id=73133, for the following platforms: - Windows - OS X (Intel platform only) - Source code .tar.gz and .zip - Documentation (cross-platform) The wxHaskell libraries (wxcore and wx) are also available from Hackage (http://hackage.haskell.org) About wxHaskell --------------- wxHaskell is a Haskell binding to the wxWidgets GUI library for recent versions of the Glasgow Haskell Compiler. It provides a native look and feel on Windows, OS X and Linux, and a medium level programming interface. The main project page for wxHaskell is at http://wxhaskell.sourceforge.net. The latest source code for wxHaskell can always be obtained from http://darcs.haskell.org/wxhaskell. There are developer (wxhaskell-devel(a)lists.sourceforge.net and user (wxhaskell-users(a)lists.sourceforge.net) mailing lists, and a wiki page at http://haskell.org/haskellwiki/WxHaskell which can provide more information to those interested. The C language binding for wxHaskell was derived from an original C language binding created for the Eiffel programming language by the ELJ project (http://elj.sourceforge.net) Non backward compatible changes: - Preliminary Cabal / Hackage support - Added "--global" argument to configure script - Added "--user" argument to configure script - Changed wxhaskell official web page to Haskell wiki at http://haskell.org/haskellwiki/WxHaskell - Changed official darcs repository to code.haskell.org - Adapted the wxHaskell C-layer to work with wxWidgets 2.8 - Adapted some part of wxcore API to be able to refer to wxWidgets 2.8 documentation for wxcore functions - Added "TopLevelWindow", which mainly removes some functionality from "Frame" - Changed "--with-stc" argument to "--with-contrib" - Removed "Wave" type synonym Backward compatible additions: - Added support for using XRC resource files to load most controls and menus attached to frames. - Added sample file showing how to use XRC support to attach command handlers to menu items - Added sample file showing how to use properties with many controls. - Added "--enable-optimization" argument to configure script - Added "--O*" argument to configure script - Added "--enable-library-profiling" argument to configure script - Added "--p" argument to configure script - Added "-fvia-C" argument to configure script. And moved this compilation flag to configure script - Added Image / ByteString conversion functions - Adapted the configuration to work with GHC 6.10. - Changed "Var" type synonym from "IORef" to stm's "TVar" for thread safety - Changed "imageGetPixelArray" and "imageCreateFromPixelArray" to be more flexible. - Changed "Point", "Size", "Vector" and "Rect" to be type synonym. - Added "wxcMilliSleep". Now, "wxcAppUSleep" is deprecated. Use "wxcMilliSleep" instead - Added very experimental wxGraphicsContext support - Added wxSVGFileDC functions Bugfixes: - Applied DEPRECATED pragma to old deprecated functions. Just documented in Haddock before. - Fixed "processExecAsync" hangs Windows GUI-only program - Fixed Windows binary install problem when path with spaces (bug 1400488) - Probably fixed the applicattion failed to initialize properly when using Windows binary. -- Jeremy O'Donoghue jeremy.odonoghue(a)gmail.com -- Jeremy O'Donoghue jeremy.odonoghue(a)gmail.com

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Haskell Weekly News: Issue 99 - January 3, 2009
by Brent Yorgey 03 Jan '09

03 Jan '09

--------------------------------------------------------------------------- Haskell Weekly News http://sequence.complete.org/hwn/20090103 Issue 99 - January 03, 2009 --------------------------------------------------------------------------- Welcome to issue 99 of HWN, a newsletter covering developments in the [1]Haskell community. Happy new year to all! May 2009 be a year full of joy, family, friends, professional success, much Haskell hacking, and a minimal number of rabid weasels. Just in case. Announcements #haskell IRC channel reaches 600 users. Don Stewart [2]announced that 7 years after its inception, under the guiding hand of Shae Erisson (aka shapr), the [3]#haskell IRC channel on freenode has reached 600 concurrent users! citeproc-hs-0.2. andrea rossato [4]announced the release of [5]citeproc-hs-0.2, a Haskell implementation of the Citation Style Language, which adds a Bibtex like citation and bibliographic formatting and generation facility to [6]pandoc. This version adds support for citation collapsing, a wrapper around [7]hs-bibutils, and some [8]API documentation. hs-bibutils-0.1. andrea rossato [9]announced the first release of [10]hs-bibutils, Haskell bindings to Chris Putnam's [11]bibutils. Bibutils is a library and a set of bibliographic utilities to interconvert between various bibliography database formats using a common MODS-format XML intermediate. Haskell koans. Gwern Branwen [12]issued an RFK (Request for [13]Koans), following the success of his CFH (Call for [14]Haiku). [ANN] Haskell web server + wiki: salvia-0.0.4 + orchid-0.0.6. Sebastiaan Visser [15]announced the release of three new packages: [16]salvia, a lightweight modular web server framework; [17]orchid, a(nother) wiki written in Haskell, using Darcs as a versioning back-end and Salvia as the application server; and [18]orchid-demo, a simple demo application using Salvia and Orchid to serve an example darcs repository. You can play around with an [19]online demo. gitit-0.4.1, recaptcha-0.1. John MacFarlane [20]announced the release of [21]gitit-0.4.1, a wiki program that stores pages in a git repository. This release adds support for (optional) captchas, using the reCAPTCHA service. The reCAPTCHA code has been packaged as a separate library on Hackage, [22]recaptcha. monte-carlo-0.2, gsl-random-0.2.3. Patrick Perry [23]announced the release of a new version of the [24]monte-carlo package. The new version includes a more general type class, MonadMC, which allows all the functions to work in both MC and MCT monads; functions to sample from discrete distributions, and functions to sample subsets. There is also a [25]quick tutorial. Reading group for Programming Collective Intelligence. Creighton Hogg [26]announced that he would like to start a small group for the O'Reilly book [27]Programming Collective Intelligence, to work through translating some of the examples to Haskell. Email Creighton if you are interested in participating. Maintaining laziness. Henning Thielemann [28]announced that he has written a [29]tutorial on how to make functions lazy and how to test whether they are actually lazy. Request for feedback: Understanding Haskell Monads. Ertugrul Soeylemez [30]requested feedback on a new [31]monad tutorial. Discussion How do we decide on the new logo?. Fritz Ruehr began a [32]discussion of how to go about choosing a winner of the [33]Great 2009 Haskell Logo Contest. Weigh in if you care! Jobs Two Positions as Associate Professor in Software Engineering at Chalmers University. Koen Claessen [34]announced the availability of [35]two positions as Associate Professor at Chalmers University in Gothenburg, Sweden, within the division of Software Engineering and Technology at the department of Computer Science and Engineering. The application deadline is January 12, 2009. Blog noise [36]Haskell news from the [37]blogosphere. * GHC / OpenSPARC Project: [38]Bootstrapping. * Dan Piponi (sigfpe): [39]Rewriting Monadic Expressions with Template Haskell. * GHC / OpenSPARC Project: [40]Fighting dependencies. * GHC / OpenSPARC Project: [41]A new year and a new project. * Alson Kemp: [42]2009: The Year Of Hackage. * Patrick Perry: [43]Monte Carlo Poker Odds. * Joachim Breitner: [44]Handling explicit and implicit recursion in Haskell data. * Luke Palmer: [45]Domain Convergence. * Eric Kow (kowey): [46]riot is almost a Haskell mail client. * John Goerzen (CosmicRay): [47]Real World Haskell update. * Alson Kemp: [48]A Plea For "cabal install". * Alson Kemp: [49]Cyptol on Slashdot. Quotes of the Week * lilac: <bohdan> how do I see the number of reductions required to calculate something? <lilac> bohdan: the usual method is to ask Cale to reduce it by hand :) * conal: If it's purely functional, how do you *do* anything? You don't ;-) * ddarius: The opposite ends of CS meet in the Haskell world. * EvilTerran: forcedYet :: a -> Bool; forcedYet x = x `seq` True -- :P * bmh: I dream in folds. One day I'll dream in monads. * sclv: dreaming is a monad. About the Haskell Weekly News New editions are posted to [50]the Haskell mailing list as well as to [51]the Haskell Sequence and [52]Planet Haskell. [53]RSS is also available, and headlines appear on [54]haskell.org. To help create new editions of this newsletter, please see the information on [55]how to contribute. Send stories to byorgey at cis dot upenn dot edu. The darcs repository is available at darcs get [56]http://code.haskell.org/~byorgey/code/hwn/ . References 1. http://haskell.org/ 2. http://article.gmane.org/gmane.comp.lang.haskell.cafe/49824 3. http://haskell.org/haskellwiki/IRC_channel 4. http://article.gmane.org/gmane.comp.lang.haskell.general/16709 5. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/citeproc-hs 6. http://johnmacfarlane.net/pandoc/ 7. http://code.haskell.org/hs-bibutils/ 8. http://code.haskell.org/citeproc-hs/docs/ 9. http://article.gmane.org/gmane.comp.lang.haskell.general/16708 10. http://code.haskell.org/hs-bibutils/ 11. http://www.scripps.edu/~cdputnam/software/bibutils/ 12. http://article.gmane.org/gmane.comp.lang.haskell.cafe/49774 13. http://haskell.org/haskellwiki/Koans 14. http://haskell.org/haskellwiki/Haiku 15. http://article.gmane.org/gmane.comp.lang.haskell.cafe/49759 16. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/salvia 17. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/orchid 18. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/orchid-demo 19. http://funct.org/wiki/] 20. http://article.gmane.org/gmane.comp.lang.haskell.cafe/49747 21. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/gitit 22. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/recaptcha 23. http://article.gmane.org/gmane.comp.lang.haskell.cafe/49739 24. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/monte-carlo 25. http://quantile95.com/2008/12/31/monte-carlo-poker-odds/ 26. http://article.gmane.org/gmane.comp.lang.haskell.cafe/49716 27. http://tinyurl.com/7x4rga 28. http://article.gmane.org/gmane.comp.lang.haskell.cafe/49655 29. http://www.haskell.org/haskellwiki/Maintaining_laziness 30. http://article.gmane.org/gmane.comp.lang.haskell.cafe/49546 31. http://ertes.de/articles/monads.html 32. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/49833 33. http://haskell.org/haskellwiki/Haskell_logos/New_logo_ideas 34. http://article.gmane.org/gmane.comp.lang.haskell.general/16712 35. http://www.chalmers.se/cse/EN/news/vacancies/positions/two-positions-as 36. http://planet.haskell.org/ 37. http://haskell.org/haskellwiki/Blog_articles 38. http://ghcsparc.blogspot.com/2009/01/building.html 39. http://sigfpe.blogspot.com/2009/01/rewriting-monadic-expressions-with.html 40. http://ghcsparc.blogspot.com/2009/01/in-in-morning.html 41. http://ghcsparc.blogspot.com/2008/12/alright.html 42. http://www.alsonkemp.com/haskell/2009-the-year-of-hackage/ 43. http://quantile95.com/2008/12/31/monte-carlo-poker-odds/ 44. https://www.joachim-breitner.de/blog/archives/316-Handling-explicit-and-imp… 45. http://lukepalmer.wordpress.com/2008/12/31/domain-convergence/ 46. http://koweycode.blogspot.com/2008/12/riot-is-almost-haskell-mail-client.ht… 47. http://changelog.complete.org/archives/861-real-world-haskell-update-2 48. http://www.alsonkemp.com/haskell/a-plea-for-cabal-install/ 49. http://www.alsonkemp.com/haskell/cyptol-on-slashdot/ 50. http://www.haskell.org/mailman/listinfo/haskell 51. http://sequence.complete.org/ 52. http://planet.haskell.org/ 53. http://sequence.complete.org/node/feed 54. http://haskell.org/ 55. http://haskell.org/haskellwiki/HWN 56. http://code.haskell.org/~byorgey/code/hwn/

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#haskell IRC channel reaches 600 users
by Don Stewart 02 Jan '09

02 Jan '09

A small announcement :) 7 years after its inception, under the guiding hand of Shae Erisson (aka shapr), the #haskell IRC channel[1] on freenode has reached 600 concurrent users! It's now in the top 3 language channels by size. To chart the growth, we can note that the channel was founded in late 2001, and had slow growth till 2006, reaching 200 users in January of that year. Since then growth in the user base has been far more rapid, reaching 300 users in Dec 2006, 400 users in August 2007, 500 users by July 2008, and 600 on January 2, 2009. This puts the channel at the 7th largest community of the 7000 freenode channels, and in the top 3 language communities. For comparision, a sample of the state of the other language communities, with comments comapred to their status a year ago: #php 612 #python 604 > #haskell 602 -- up 4 ##c++ 558 ##c 506 -- down 1 #perl 502 -- down 3 #ruby-lang 288 -- down #lisp 264 ##javascript 241 #erlang 146 -- unchanged #perl6 129 -- unchanged #scheme 123 -- down #lua 102 -- unchanged #clojure 78 #ocaml 70 -- unchanged You can see the growth of the channel over here: http://haskell.org/haskellwiki/IRC_channel If you've not dropped by the channel yet, feel free to come and chat, and toss around some lambdas! :) Cheers, Don

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