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Re: ANNOUNCE: generator 0.5.1
by Yair Chuchem 16 Jul '09

16 Jul '09

Sebastian Fisher wrote: > The nested monadic tails of your lists seem more similar to the > nested monadic data described in the ICFP'09 paper with Oleg > Kiselyov and Chung-chieh Shan [1]. The ideas described in that paper > are on Hackage and your ListT seems similar to the List type in > Data.Monadic.List [2] although our version not only uses monadic > tails but also monadic heads. See [3] for a tutorial. A small correction: the tail of ListT is not monadic, but "unpacking" it (getting either a Nil or a Cons) is. If just the tail was monadic one couldn't create a list which might be empty depending on a monadic result, For example: linesFromUser :: ListT IO String linesFromUser = takeWhile (not . null) . joinM $ repeat getLine linesFromUser is a list of lines from the user until an empty line, not including the empty line. the first line entered by the user determines if the list is empty or not. cheers, Yair

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ANN: shelltestrunner 0.6 released
by Simon Michael 15 Jul '09

15 Jul '09

I'm pleased to announce the first release of shelltestrunner: a small tool for testing any command-line program by running it through "shell" tests defined with a simple file format. Each test can specify the command-line arguments, input, expected output, expected stderr output, and/or expected exit code. This was extracted from the hledger project, inspired by the tests in John Wiegley's ledger project, and uses Max Bolingbroke's test- framework. In some cases you will get a big speedup by using test- framework's parallelising feature. Example: $ shelltestrunner shelltestrunner *.test -- -j8 :args.test:1: [OK] :args.test:2: [OK] :args.test:3: [OK] :args.test:4: [OK] :early-j-option.test: [OK] :help-flag.test: [OK] etc. I hope you find it useful. Feedback, patches, or alternate packaging suggestions are welcome! Best, -Simon

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ANNOUNCE: GLURaw 1.0.0.0
by Sven Panne 14 Jul '09

14 Jul '09

A new GLURaw package has been uploaded to Hackage. It contains full support for all GLU functionality and is similar in spirit to the OpenGLRaw package, i.e. it is a 1:1 mapping of the C interface, no libraries or headers are needed at build time, and the GLU API entries are resolved dynamically at runtime. Cheers, S.

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ANNOUNCE: OpenGLRaw 1.0.1.0
by Sven Panne 14 Jul '09

14 Jul '09

A new version of the OpenGLRaw package has been uploaded to Hackage. Support for the following OpenGL extensions has been added: GL_NV_texture_shader2 GL_NV_depth_clamp GL_NV_primitive_restart GL_NV_vertex_array_range2 GL_NV_occlusion_query GL_NV_fence GL_NV_light_max_exponent GL_NV_texture_env_combine4 GL_NV_fog_distance GL_NV_register_combiners2 GL_NV_register_combiners GL_NV_light_max_exponent GL_NV_multisample_filter_hint GL_NV_texture_shader GL_NV_vertex_array_range GL_NV_texgen_emboss GL_NV_copy_depth_to_color Cheers, S.

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ANNOUNCE: ObjectName 1.0.0.0
by Sven Panne 14 Jul '09

14 Jul '09

A new (tiny) ObjectName package has been released to Hackage. It contains the class ObjectName, which corresponds to the general notion of explicitly handled identifiers for API objects, e.g. a texture object name in OpenGL or a buffer object name in OpenAL. Cheers, S.

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ANNOUNCE: StateVar 1.0.0.0
by Sven Panne 14 Jul '09

14 Jul '09

To further modularize the OpenGL/OpenAL packages, a new StateVar package has been released to Hackage. It contains state variables, which are references in the IO monad, like IORefs or parts of the OpenGL state. Cheers, S.

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20 years ago
by Bulat Ziganshin 14 Jul '09

14 Jul '09

Hello haskell, Industrial programmers often think that functional programming is "unnatural" and cannot be mastered by most of them. But 20 years ago they thought the same about OOP The first widespead OOP system was a Turbo Pascal 5.5, released 1989. i've downloaded its manual, quickly scanned it and found what i've expected: "The challenge of object-oriented programming (OOP) is that it sometimes requires you to set aside habits and ways of thinking about programming that have been considered standard for many years. Once that is done, however, OOP is simple, straight-forward, and superior for solving many of the prob- lems that plague traditional software programs." http://edn.embarcadero.com/article/images/20803/TP_55_OOP_Guide.pdf -- Best regards, Bulat mailto:Bulat.Ziganshin@gmail.com

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ANN: data-ordlist-0.0.1 and NumberSieves-0.0
by Leon Smith 13 Jul '09

13 Jul '09

Two new packages have been uploaded to Hackage, one that implements bag (multiset) and set operations on ordered lists, and another that offers three different number theoretic sieves. http://hackage.haskell.org/package/data-ordlist Data.OrdList offers many of the same kinds of operations as Data.Set, although Data.Set is likely to often be a better choice. However, this library is not intended to be used as an abstract datatype for sets and multisets, rather it is intended to be a convenient way for efficiently dealing with lists that you happen to know are ordered. It includes operations such as union, merge, exclusive union, intersection, and difference. Also notable is that it includes nub on ordered lists, as well as sortOn and nubSort functions. http://hackage.haskell.org/package/NumberSieves NumberSieves includes the Sieve of O'Neill, from "The Geniune Sieve of Eratosthenes" by Melissa O'Neill, which offers an incremental primality sieve based on priority queues. Also included are two array-based generalizations of the Sieve of Eratosthenes. The first sieves a prime divisor for each number in the sieve, which is useful if you want to factor a large quantity of small numbers. The second sieves Euler's totient, useful if you want to calculate the phi function for a large quantity of small numbers. Best, Leon

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ICFP09 Final Call for Participation
by Matthew Fluet (ICFP Publicity Chair) 13 Jul '09

13 Jul '09

===================================================================== Final Call for Participation The 14th ACM SIGPLAN International Conference on Functional Programming (ICFP 2009) http://www.cs.nott.ac.uk/~gmh/icfp09.html Edinburgh, Scotland, 31 August - 2 September 2009 ===================================================================== ***** Accommodation Deadline: July 20, 2009 ***** Due to the overlap with Edinburgh Festival, accommodations may be difficult to secure after the deadline. Reserve now! http://www.haskell.org/haskellwiki/ICFP_2009_Local_Arrangements ***** Early Registration Deadline: July 30, 2009 ***** http://www.regmaster.com/conf/icfp2009.html ICFP 2009 provides a forum for researchers and developers to hear about the latest work on the design, implementations, principles, and uses of functional programming. The conference covers the entire spectrum of work, from practice to theory, including its peripheries. Preliminary program: * Abstracts: + http://web.cecs.pdx.edu/~apt/icfp09_accepted_papers/accepted.html * Schedule: + http://web.cecs.pdx.edu/~apt/icfp09_preliminary_program.pdf * Invited speakers: + Guy Steele -- Organizing Functional Code for Parallel Execution: or, foldl and foldr Considered Slightly Harmful + Benjamin Pierce -- Lambda, the Ultimate TA: Using a Proof Assistant to Teach Programming Language Foundations + Dan Piponi -- Commutative Monads, Diagrams and Knots Schedule including related workshops: * Aug 30: ACM SIGPLAN Workshop on ML * Aug 30: ACM SIGPLAN Workshop on Generic Programming * Aug 31-Sep 2: ICFP09 * Sep 3: ACM SIGPLAN Haskell Symposium * Sep 3: ACM SIGPLAN Developer Tracks on Functional Programming * Sep 4: Commercial Users of Functional Programming * Sep 4: ACM SIGPLAN Workshop on Mechanizing Metatheory * Sep 4: ACM SIGPLAN Workshop on Approaches and Applications of Inductive Programming * Sep 5: ACM SIGPLAN Erlang Workshop * Sep 5: ACM SIGPLAN Developer Tracks on Functional Programming * Sep 5: ACM SIGPLAN Haskell Implementors Workshop Conference organizers: * General Chair: Graham Hutton (University of Nottingham) * Program Chair: Andrew Tolmach (Portland State University) * Local Arrangements Chairs: Philip Wadler (University of Edinburgh), Kevin Hammond (University of St Andrews), and Gregory Michaelson (Heriot-Watt University) * Workshop Co-Chairs: Christopher Stone (Harvey Mudd College), and Michael Sperber (DeinProgramm) * Programming Contest Chair: Andrew Gill (University of Kansas) * Publicity Chair: Matthew Fluet (Toyota Technological Institute at Chicago)

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Haskell Weekly News: Issue 125 - July 12, 2009
by Brent Yorgey 12 Jul '09

12 Jul '09

--------------------------------------------------------------------------- Haskell Weekly News http://sequence.complete.org/hwn/20090712 Issue 125 - July 12, 2009 --------------------------------------------------------------------------- Welcome to issue 125 of HWN, a newsletter covering developments in the [1]Haskell community. Announcements Announcing the new Haskell Prime process, and Haskell 2010. Simon Marlow [2]announced the new and improved [3]Haskell Prime process, and a list of proposals which are currently under consideration to be accepted into the next (2010) revision of the standard. AspectAG 0.1.1. Marcos Viera [4]announced the release of [5]AspectAG, a library of strongly typed Attribute Grammars implemented using type-level programming. Colour tutorial. Russell O'Connor [6]announced a [7]tutorial wiki page for the [8]colour library. Haskell Hack Day, Edinburgh, 30 August 2009. Eric Kow [9]announced a [10]Haskell Hack Day to be held in Edinburgh, on Sunday 30 August, before ICFP. The Hack Day will be held at the ICFP conference venue, the Royal College of Physicians. sendfile-0.3. Matthew Elder [11]announced the release of [12]sendfile-0.3, which includes a more general interface, updated documentation, and more. Gtk2hsGenerics. Michael Dever [13]announced the release of [14]Gtk2hsGenerics, a package which contains utility functions for extracting from and adding to stores. darcs 2.3 beta 2. Petr Rockai [15]announced that darcs 2.3 beta 2 is available for testing. It can be installed using the [16]darcs-beta package on Hackage (be sure to 'cabal update' first). The new beta release adds index upgrade functionality to hashed-storage, and now uses an architecture-independent index format. hsparql, a SPARQL query generator/DSL and client. Jeff Wheeler [17]announced the first version of [18]hsparql, which makes it easy to query SPARQL-compliant servers using a relatively intuitive DSL and very simple client. SPARQL is a SQL-ish query language for stores of RDF data. Hayoo! beta 0.4. Timo B. [19]announced the next beta version 0.4 of [20]Hayoo!, the Haskell API search engine with find-as-you-type and suggestions. This release includes some major changes to the web interface, including the ability to display the full description of a function, and some example queries featured on the start page, as well as an updated search index. texmath 0.1.0.1 - conversion of LaTeX math to MathML. John MacFarlane [21]announced an early release of [22]texmath, a Haskell library for converting LaTeX math formulas to MathML. The package includes a standalone test program, testTeXMathML, and a CGI script, texmath-cgi, that can be used in web apps. You can see demos of the script [23]here and [24]here. BostonHaskell: Next meeting - July 16th at MIT CSAIL Reading Room (32-G882). Ravi Nanavati [25]announced the July meeting of the [26]Boston Area Haskell Users' Group, to be held Thursday, July 16th from 6:30pm - 8:30pm in the MIT CSAIL Reading Room. Scheduled talks include "An Introduction to GHC Hacking" by Alec Heller, and "Haskell on the iPhone" by Ryan Trinkle. There are still openings for Lightning Talks (5-minute talk, 2-minute Q&A). See the announcement for more details. AC-Vector, AC-Colour and AC-EasyRaster-GTK. Andrew Coppin [27]announced the release of three packages: [28]AC-Vector, which provides unboxed vectors of Doubles with arithmetic, dot product and cross product, and a few other useful items; [29]AC-Colour, which provides two simple RGB color types, optimized for simplicity and speed; and [30]AC-EasyRaster-GTK, a layer over Gtk2hs which provides easy pixel-twiddling functionality. Google Summer of Code Progress updates from participants in the 2008 [31]Google Summer of Code. Haddock improvements. Isaac Dupree has had a [32]good deal of success getting cross-package documentation to work, with a few remaining loose ends. space profiling. Gergely Patai's profile graphing application [33]is now capable of connecting to a profile relay server that can broadcast the heap profile of its associated process on the fly, so it is now possible to attach an observer to a program that was started earlier. He now plans to shift to working on a history manager. fast darcs. Petr Rockai has produced [34]another darcs 2.3 beta release, and has done more work on [35]designing an efficient storage system. Discussion Leaner Haskell.org frontpage. haskell [36]proposed a new design for the haskell.org front page. Bikeshedding ensues, news at 11. exercise - a completely lazy sorting algorithm. Petr Pudlak [37]asked whether it is possible to write a lazy sorting algorithm which allows access to the kth item of the sorted output in linear time, for all k. An interesting discussion and mind-expanding code followed. Implementing Las Vegas algorithms in Haskell. Matthias Görgens began a [38]discussion on implementing Las Vegas algorithms, which use a source of randomness but have results which are still deterministic. What should the type of such functions be? Is it OK to use unsafePerformIO in their definition? Blog noise [39]Haskell news from the [40]blogosphere. Blog posts from people new to the Haskell community are marked with >>>, be sure to welcome them! * Petr Rockai: [41]Designing Storage for darcs. * >>> haskelladdict: [42]Having fun sorting with Haskell. * Jeff Heard: [43]C2HS example: To save other people frustration. * JP Moresmau: [44]Mazes of Monad: 1.0.5 and (maybe) final version uploaded. * Sean Leather: [45]Fun and generic things to do with EMGM at the London HUG. * Greg Bacon: [46]Gyrigrams. * Magnus Therning: [47]Making a choice from a list in Haskell, Vty (part 2). * Jeff Heard: [48]A quick buster example. * Jeff Heard: [49]An ugly force-directed layout implementation. * Petr Rockai: [50]darcs 2.3 beta 2. * Isaac Dupree: [51]Cross-package documentation going well!. * >>> dasuxullebt: [52]I (don't) like Haskell. * Holumbus: [53]Some Hayoo! Improvements. * David Amos: [54]Conjugacy classes, part 2. * Michael Snoyman: [55]hack-handler-webkit. * Dan Piponi (sigfpe): [56]A Monad for Combinatorial Search with Heuristics. * Greg Bacon: [57]A programmable semicolon explained. * Holumbus: [58]Another Hayoo! Update. * Gergely Patai: [59]Remote profiling at your fingertips. * The GHC Team: [60]Visualising the Haskell package dependency graph. * Bryan O'Sullivan: [61]First steps with Haskell text API improvement. * Paul Hudak: [62]Haskell and the Arts. * >>> John Gunderman: [63]Haskell Cabal in Ubuntu. * Sebastian Sylvan: [64]Ray tracing signed distance functions. Quotes of the Week * SimonPJ: [re: class constraints on data declarations] In GHC's source code these contexts are consistently called stupid_theta. * JN: this tutorial just introduced _|_ and called it bottom. I assume that's because it looks like an ass? * uman: so you can pass functions around as objects... this sounds like JavaScript * Twey: Mr. Wing, sir, if you are listening: you have the I.Q. of a semolina pudding. And your homepage is full of <font> tags. I'm not sure which is the greater insult, but at least one is objectively true. * jmcarthur: #haskell: Overwhelmingly helpful. * lilac: class Monad m where / return and Kleisli compose / must form a monoid <lilac> that's my new monad tutorial haiku <jmcarthur> i think that is the best monad tutorial i have ever read * dcoutts: make sure happy is on your path and it'll all be ok * ski: my answer to that is : don't deduce, denote! * roco: guys i have problem, does anybody know programming ? * dhjdhj: All new features added to C++ are intended to fix previously new features added to C++ About the Haskell Weekly News New editions are posted to [65]the Haskell mailing list as well as to [66]the Haskell Sequence and [67]Planet Haskell. [68]RSS is also available, and headlines appear on [69]haskell.org. To help create new editions of this newsletter, please see the information on [70]how to contribute. Send stories to byorgey at cis dot upenn dot edu. The darcs repository is available at darcs get [71]http://code.haskell.org/~byorgey/code/hwn/ . References 1. http://haskell.org/ 2. http://www.haskell.org//pipermail/haskell/2009-July/021472.html 3. http://hackage.haskell.org/trac/haskell-prime/wiki/Process 4. http://www.haskell.org//pipermail/haskell/2009-July/021475.html 5. http://hackage.haskell.org/package/AspectAG 6. http://www.haskell.org//pipermail/haskell-cafe/2009-July/064065.html 7. http://www.haskell.org/haskellwiki/Colour 8. http://hackage.haskell.org/package/colour 9. http://article.gmane.org/gmane.comp.lang.haskell.general/17345 10. http://www.haskell.org/haskellwiki/Hac7 11. http://article.gmane.org/gmane.comp.lang.haskell.general/17343 12. http://hackage.haskell.org/package/sendfile 13. http://article.gmane.org/gmane.comp.lang.haskell.general/17336 14. http://hackage.haskell.org/package/Gtk2hsGenerics 15. http://article.gmane.org/gmane.comp.lang.haskell.cafe/61071 16. http://hackage.haskell.org/package/darcs%2Dbeta 17. http://article.gmane.org/gmane.comp.lang.haskell.cafe/61062 18. http://hackage.haskell.org/package/hsparql 19. http://article.gmane.org/gmane.comp.lang.haskell.cafe/61060 20. http://holumbus.fh-wedel.de/hayoo 21. http://article.gmane.org/gmane.comp.lang.haskell.cafe/61049 22. http://hackage.haskell.org/package/texmath 23. http://johnmacfarlane.net/texmath.xhtml 24. http://johnmacfarlane.net/texmath.html 25. http://article.gmane.org/gmane.comp.lang.haskell.cafe/61003 26. http://www.haskell.org/haskellwiki/Boston_Area_Haskell_Users%27_Group 27. http://article.gmane.org/gmane.comp.lang.haskell.cafe/60944 28. http://hackage.haskell.org/package/AC-Vector 29. http://hackage.haskell.org/package/AC-Colour 30. http://hackage.haskell.org/package/AC-EasyRaster-GTK 31. http://hackage.haskell.org/trac/summer-of-code/wiki/SoC2008 32. http://haddock2009.wordpress.com/2009/07/09/cross-package-documentation-goi… 33. http://just-bottom.blogspot.com/2009/07/remote-profiling-at-your-fingertips… 34. http://web.mornfall.net/blog/darcs_2.3_beta_2.html 35. http://web.mornfall.net/blog/designing_storage_for_darcs.html 36. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/61082 37. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/60981 38. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/60998 39. http://planet.haskell.org/ 40. http://haskell.org/haskellwiki/Blog_articles 41. http://web.mornfall.net/blog/designing_storage_for_darcs.html 42. http://haskelladdict.wordpress.com/2009/07/11/having-fun-sorting-with-haske… 43. http://vis.renci.org/jeff/2009/07/10/c2hs-example-to-save-other-people-frus… 44. http://jpmoresmau.blogspot.com/2009/07/mazes-of-monad-105-and-maybe-final.h… 45. http://feedproxy.google.com/~r/splonderzoek/~3/qnt94yp_Er4/fun-and-generic-… 46. http://feedproxy.google.com/~r/gbacon/~3/QKPjQ0Fxl_4/gyrigrams.html 47. http://therning.org/magnus/archives/689 48. http://vis.renci.org/jeff/2009/07/09/a-quick-buster-example/ 49. http://vis.renci.org/jeff/2009/07/09/an-ugly-force-directed-layout-implemen… 50. http://web.mornfall.net/blog/darcs_2.3_beta_2.html 51. http://haddock2009.wordpress.com/2009/07/09/cross-package-documentation-goi… 52. http://uxul.wordpress.com/2009/07/09/i-dont-like-haskell/ 53. http://holumbus.fh-wedel.de/blog/?p=24 54. http://haskellformaths.blogspot.com/2009/07/conjugacy-classes-part-2.html 55. http://blog.snoyman.com/2009/07/08/hack-handler-webkit/ 56. http://blog.sigfpe.com/2009/07/monad-for-combinatorial-search-with.html 57. http://feedproxy.google.com/~r/gbacon/~3/UGYWKr-huLY/programmable-semicolon… 58. http://holumbus.fh-wedel.de/blog/?p=23 59. http://just-bottom.blogspot.com/2009/07/remote-profiling-at-your-fingertips… 60. http://ghcmutterings.wordpress.com/2009/07/06/visualising-the-haskell-packa… 61. http://www.serpentine.com/blog/2009/07/06/first-steps-with-haskell-text-api… 62. http://www.infoq.com/presentations/haskell-arts-paul-hudak 63. http://sporkcode.wordpress.com/2009/07/05/haskell-cabal-in-ubuntu/ 64. http://sebastiansylvan.spaces.live.com/blog/cns!4469F26E93033B8C!173.entry 65. http://www.haskell.org/mailman/listinfo/haskell 66. http://sequence.complete.org/ 67. http://planet.haskell.org/ 68. http://sequence.complete.org/node/feed 69. http://haskell.org/ 70. http://haskell.org/haskellwiki/HWN 71. http://code.haskell.org/~byorgey/code/hwn/

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