- Haskell - Haskell.org

ANNOUNCE: darcs 2.5
by Reinier Lamers 30 Oct '10

30 Oct '10

Hi all, The darcs team is proud to announce the release of darcs 2.5. Darcs 2.5 contains many improvements over the 2.4 series. Most notable are the performance improvements in record and pull and the --bisect option for trackdown. The easiest way to install darcs 2.5 is using the Haskell Platform [1]. If you have installed the Haskell Platform or cabal-install, you can install this beta release by doing: $ cabal update $ cabal install darcs Alternatively, you can download the tarball from http://darcs.net/releases/darcs-2.5.tar.gz and build it by hand as explained in the README file. What's New ---------- A list of important changes since darcs 2.4.4: * trackdown can now do binary search with the --bisect option * darcs always stores patch metadata encoded with UTF-8 * diff now supports the --index option * amend-record now supports the --ask-deps option * apply now supports the --match option * amend-record has a new --keep-date option * inventory-changing commands (like record and pull) now operate in constant time with respect to the number of patches in the repository * the push, pull, send and fetch commands no longer change the default repository address by default * the --edit-description option is now on by default for the send command Issues resolved since darcs 2.4.4: * 64: store metadata as UTF-8 * 121: add --ask-deps support to amend-record * 643: darcs send -o outputs remote repo email address * 1159: avoid bogus repository cache entries * 1176: caches interfere with --remote-repo flag * 1208: add trackdown --bisect * 1210: global cache gets recorded in _darcs/prefs/sources * 1232: darcs convert copies _darcs/prefs/prefs * 1250: check for newlines in setpref values * 1277: percolate repository format errors correctly * 1288: the main darcs code now compiles and runs with witnesses * 1290: support diff --index * 1337: don't show unrelated patches in darcs changes on untracked path * 1389: change predist pref to point people to use 'cabal sdist' * 1427: accept gzipped patch bundles in darcs apply * 1456: make dist write more portable archives * 1473: make annotate accept '.' as argument * 1503: prefer local caches to remote ones * 1713: shorter interactive prompts * 1716: allow mail header lines of all whitespace in test * 1719: do not back up files when no conflict markers are inserted * 1726: don't consider all files with _darcs prefix boring * 1739: make ColorPrinter handle characters > 255 * 1763: use correct filename encoding in conflictors * 1765: refuse to remove non-tracked directories recursively * 1769: add support for --match 'comment ...' * 1784: push and pull print remote address right away * 1815: work around Cabal sdist permissions issue * 1817: fix support for external merge tools * 1824: avoid PACKAGE_VERSION under Windows * 1825: do not omit important prims in unrecordedChanges w/ files * 1860: (un)applying move patches doesn't corrupt pristine * 1861: fix typo in --no-boring help * 1874: recognise network tests on cabal test command line * 1875: avoid accidentally setting default * 1879: notice unexpected commute failure on merge * 1887: add a missing newline to --list-options output * 1893: move fields of conditional builds within scope of condition * 1898: notify user when they can use set-default * 1913: sort changes in treeDiff Reporting bugs -------------- If you have an issue with darcs 2.5, you can report it via the web on http://bugs.darcs.net/ . You can also report bugs by email to bugs(a)darcs.net. Kind Regards, the darcs release manager, Reinier Lamers [1]: You can download the Haskell platform from http://hackage.haskell.org/platform/

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Haskell Weekly News: Issue 156 - October 27, 2010
by Daniel Santa Cruz 28 Oct '10

28 Oct '10

Welcome to issue 156 of the HWN, a newsletter covering developments in the [1]Haskell community in the week of October 17 - 28. I did not manage to filter out good posts from Haskell-Cafe this week. If you see a thread in -cafe that you think would be good to share with the community, please do share it with me. I need to find a better way of keeping up with the mountain of posts to that list. There were a total of 34 new stories posted to the Haskell Reddit channel (+10), 47 new questions taged with Haskell in StackOverflow (+20), and 332 messages posted to Haskell-Cafe (-76). So, what was hot last week? Announcements John Hughes [2]announced that the Functional Programming group at Chalmers is recruiting a postdoctoral researcher for a two year position, starting as soon as possible. Wouter Swierstra [3]called for workshop and co-located event proposals for the ICFP 2011 in Tokyo, Japan. Zhong Shao [4]informed us that the Department of Computer Science at Yale University is seeking applicants for a PostDoc and PhD positions in the broad area of certified software. Josh Tripplett wrote in to tell us about Ore, a [5]packaging system for Ruby inspired by Haskell's Cabal! According to [6]this haskell community calendar, there are 2 events to take note happening next week: The Haskell Communities & Activities Report submission deadline on Nov 1, and BelHac (in Ghent, Belgium) on Nov 5 - 7. Top Reddit Stories * The Haskell Platform is now in Ubuntu Domain: packages.ubuntu.com Score: 58, Comments: 5 On Reddit: http://www.reddit.com/r/haskell/comments/dtffi/the_haskell_platform_is_now_… Original: http://packages.ubuntu.com/maverick/haskell-platform * ghcjs: Haskell to Javascript: now released Domain: github.com Score: 36, Comments: 4 On Reddit: http://www.reddit.com/r/haskell/comments/dujnb/ghcjs_haskell_to_javascript_… Original: http://github.com/sviperll/ghcjs#readme * GHC Blog: New directions for Template Haskell Domain: hackage.haskell.org Score: 32, Comments: 3 On Reddit: http://www.reddit.com/r/haskell/comments/dtav8/ghc_blog_new_directions_for_… Original: http://hackage.haskell.org/trac/ghc/blog/Template%20Haskell%20Proposal * A brief tale of faster equality Domain: serpentine.com Score: 27, Comments: 10 On Reddit: http://www.reddit.com/r/haskell/comments/dt76u/a_brief_tale_of_faster_equal… Original: http://www.serpentine.com/blog/2010/10/19/a-brief-tale-of-faster-equality/ * MTL 2.0 has been uploaded good bye old mtl, hello monads-fd! Domain: hackage.haskell.org Score: 25, Comments: 6 On Reddit: http://www.reddit.com/r/haskell/comments/dx8ml/mtl_20_has_been_uploaded_goo… Original: http://hackage.haskell.org/package/mtl-2.0.0.0 * Haskell Rapid Transit Domain: mtnviewmark.wordpress.com Score: 23, Comments: 4 On Reddit: http://www.reddit.com/r/haskell/comments/duqp0/haskell_rapid_transit/ Original: http://mtnviewmark.wordpress.com/2010/10/21/haskell-rapid-transit/ * mathblog: A program for creating and managing a static, mathematically-inclined weblog Domain: hackage.haskell.org Score: 20, Comments: 0 On Reddit: http://www.reddit.com/r/haskell/comments/duh1o/mathblog_a_program_for_creat… Original: http://hackage.haskell.org/package/mathblog-0.2 * Lazy Type-Level Programming: nice trick by Max Bolingbroke Domain: haskell.org Score: 20, Comments: 1 On Reddit: http://www.reddit.com/r/haskell/comments/duu54/lazy_typelevel_programming_n… Original: http://www.haskell.org/pipermail/haskell-cafe/2010-October/085307.html * Let's build a compiler (in Haskell): Part 12 - Introducing the State Monad Domain: alephnullplex.appspot.com Score: 19, Comments: 14 On Reddit: http://www.reddit.com/r/haskell/comments/du38c/lets_build_a_compiler_in_has… Original: http://alephnullplex.appspot.com/blog/view/2010/10/19/lbach-introducing-the… * What's the status of Haskell on the iPhone? Domain: self.haskell Score: 18, Comments: 5 On Reddit: http://www.reddit.com/r/haskell/comments/dsyij/whats_the_status_of_haskell_… Original: /r/haskell/comments/dsyij/whats_the_status_of_haskell_on_the_iphone/ Top StackOverflow Questions * Question (votes: 33, answers: 8): Best explanation for Languages without Null Read on SO: http://stackoverflow.com/questions/3989264/best-explanation-for-languages-w… * Question (votes: 16, answers: 6): Saving my running toplevel for later Read on SO: http://stackoverflow.com/questions/3966925/saving-my-running-toplevel-for-l… * Question (votes: 10, answers: 2): What's the difference between undefined in Haskell and null in Java? Read on SO: http://stackoverflow.com/questions/3962939/whats-the-difference-between-und… * Question (votes: 9, answers: 2): Is FC++ used by any open source projects? Read on SO: http://stackoverflow.com/questions/3995942/is-fc-used-by-any-open-source-pr… * Question (votes: 8, answers: 3): What is the difference between forall a. [a] and [forall a. a]? Read on SO: http://stackoverflow.com/questions/3961851/what-is-the-difference-between-f… * Question (votes: 6, answers: 5): In Haskell, is there any way to express that a type should be an instance of a typeclass in more than one way? Read on SO: http://stackoverflow.com/questions/3998732/in-haskell-is-there-any-way-to-e… * Question (votes: 5, answers: 3): Pure exceptions in Haskell Read on SO: http://stackoverflow.com/questions/3961536/pure-exceptions-in-haskell * Question (votes: 5, answers: 1): How to use fromInteger with no implicit prelude in Haskell? Read on SO: http://stackoverflow.com/questions/3969413/how-to-use-frominteger-with-no-i… * Question (votes: 5, answers: 7): Is this Fibonacci sequence function recursive? Read on SO: http://stackoverflow.com/questions/3980756/is-this-fibonacci-sequence-funct… * Question (votes: 5, answers: 1): Any Sparse Linear Algebra package in Haskell? Read on SO: http://stackoverflow.com/questions/3995323/any-sparse-linear-algebra-packag… Quotes of the Week If you'd like to have a quote you see in IRC here, use the following syntax: @remember WhoSaidIt Quote. I'm currently scrapping IRC logs to find this data, so don't worry if lambdabot doesn't cooperate. * chrisdone: Production of two-handed use langes Schwerts with long flambard blades and heavily category-theoretically decorated guards, katzbalgers, axes, mail and Macedonian quality defence pikes. Lambda Knights need to be prepared for the inevitable battle against success. HackageDB Updates Who contributed, and what got uploaded? * AlbertoRuiz: hmatrix-special * AlessandroVermeulen: lhs2TeX-hl * AlexanderSolla: Facts * AlexeyKhudyakov: histogram-fill, monoid-statistics, mwc-random-monad * AntonKholomiov: csound-expression, temporal-media * AristidBreitkreuz: monadLib-compose, xml-monad * AycanIrican: hweblib * BasVanDijk: concurrent-extra, dstring, explicit-iomodes, explicit-iomodes-bytestring, explicit-iomodes-text, repr, string-combinators, threads, usb, usb-enumerator * BryanOSullivan: text * ChrisKuklewicz: regex-tdfa, regex-tdfa-unittest * ClaudeHeilandAllen: gmndl, qd * DanielDiaz: HaTeX * DonaldStewart: plugins * EugeneKirpichov: splot * GregWeber: xss-sanitize * HenkJanVanTuyl: GeBoP * HolgerReinhardt: amqp * HugoPacheco: pointless-rewrite * JamesCook: priority-queue, queue * JeremyShaw: formlets-hsp * JoelCrisp: bindings-gts * JohanTibell: network * JohnMillikin: anansi, cpython, enumerator-fd, enumerator, enumerator-tf, yajl-enumerator, yajl * JonathanDaugherty: mathblog * JudeNagurney: augeas * KetilMalde: a50, flower * MagnusTherning: archlinux, archlinux-web, cabal2arch * MasatakeDaimon: bindings-audiofile, bindings-EsounD * MichaelIlseman: yaml-light * MichaelSnoyman: authenticate, convertible-text, data-object-json, data-object, data-object-yaml, hamlet, mime-mail, wai-handler-devel, wai-handler-webkit, web-encodings, yesod-auth, yesod * MichelBoucey: ip6addr * NeilMitchell: hlint * OlegBelozeorov: xmms2-client-glib, xmms2-client * OscarFinnsson: text-xml-qq * PeterSimons: vty * PetrRockai: darcs-fastconvert * RoelVanDijk: base-unicode-symbols, containers-unicode-symbols * RyanNewton: wordsetdiff * SimonMarlow: stm * StephenBlackheath: hexpat * StephenTetley: wumpus-basic, wumpus-microprint, wumpus-tree * ThomasDuBuisson: control-event, crypto-api, gps, hsXenCtrl, ipc * TomHawkins: fountain * ViktorDevecseri: bloxorz About the Haskell Weekly News New editions are posted to [7]the Haskell mailing list as well as to [8]the Haskell Sequence and [9]Planet Haskell. [10]RSS is also available, and headlines appear on [11]haskell.org. To help create new editions of this newsletter, please send stories to dstcruz * at * gmail * dot * com. The code used to produce this version of the newsletter is not yet publicly available, as it is a complete hack designed to get things started again. Until next time, Daniel Santa Cruz References 1. http://haskell.org/ 2. http://article.gmane.org/gmane.comp.lang.haskell.general/18252 3. http://article.gmane.org/gmane.comp.lang.haskell.general/18260 4. http://article.gmane.org/gmane.comp.lang.haskell.general/18261 5. http://postmodern.github.com/2010/10/25/mining-rubygems-from-ore.html 6. https://sites.google.com/site/haskellcommunitycalendar/ 7. http://www.haskell.org/mailman/listinfo/haskell 8. http://sequence.complete.org/ 9. http://planet.haskell.org/ 10. http://sequence.complete.org/node/feed 11. http://haskell.org/

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ANN: mutable-iter
by John Lato 26 Oct '10

26 Oct '10

Dear all: I am pleased to announce the initial release of "mutable-iter"[1], an extension to the iteratee package which uses mutable buffers. This allows for iteratees to act upon a mutable buffer, which means that processing can occur without performing any extra allocations. This may be useful for applications in which garbage collections interfere with processing (e.g. real-time applications), or under severe memory pressure. This package is highly experimental and somewhat low-level; bug reports and suggestions are welcome! Thanks, John [1] http://hackage.haskell.org/package/mutable-iter

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Call for Contributions - Haskell Communities and Activities Report, November 2010 edition
by Janis Voigtländer 26 Oct '10

26 Oct '10

Dear all, It is time to collect contributions for the 19th edition of the ================================================================ Haskell Communities & Activities Report http://www.haskell.org/communities/ Submission deadline: 1 November 2010 (please send your contributions to hcar at haskell.org, in plain text or LaTeX format) ================================================================ This is the short story: * If you are working on any project that is in some way related to Haskell, please write a short entry and submit it. Even if the project is very small or unfinished or you think it is not important enough -- please reconsider and submit an entry anyway! * If you are interested in an existing project related to Haskell that has not previously been mentioned in the HCAR, please tell me, so that I can contact the project leaders and ask them to submit an entry. * Feel free to pass on this call for contributions to others that might be interested. More detailed information: The Haskell Communities & Activities Report is a bi-annual overview of the state of Haskell as well as Haskell-related projects over the last, and possibly the upcoming six months. If you have only recently been exposed to Haskell, it might be a good idea to browse the May 2010 edition -- you will find interesting topics described as well as several starting points and links that may provide answers to many questions. Contributions will be collected until the submission deadline. They will then be compiled into a coherent report that is published online as soon as it is ready. As always, this is a great opportunity to update your webpages, make new releases, announce or even start new projects, or to talk about developments you want every Haskeller to know about! Looking forward to your contributions, Janis (current editor) FAQ: Q: What format should I write in? A: The required format is a LaTeX source file, adhering to the template that is available at: http://haskell.org/communities/11-2010/template.tex There is also a LaTeX style file at http://haskell.org/communities/11-2010/hcar.sty that you can use to preview your entry. If you do not know LaTeX, then use plain text. If you modify an old entry that you have written for an earlier edition of the report, you should already have received your old entry as a template (provided I have your valid email address). Please modify that template, rather than using your own version of the old entry as a template. Q: Can I include images? A: Yes, you are even encouraged to do so. Please use .jpg format, then. Q: Should I send files in .zip archives or similar? A: No, plain file attachements are the way. If you have several entries to submit, it helps if you send them in separate emails. Q: How much should I write? A: Authors are asked to limit entries to about one column of text. This corresponds to approximately one page, or 40 lines of text, with the above style and template. A general introduction is helpful. Apart from that, you should focus on recent or upcoming developments. Pointers to online content can be given for more comprehensive or "historic" overviews of a project. Images do not count towards the length limit, so you may want to use this opportunity to pep up entries. There is no minimum length of an entry! The report aims for being as complete as possible, so please consider writing an entry, even if it is only a few lines long. Q: Which topics are relevant? A: All topics which are related to Haskell in some way are relevant. We usually had reports from users of Haskell (private, academic, or commercial), from authors or contributors to projects related to Haskell, from people working on the Haskell language, libraries, on language extensions or variants. We also like reports about distributions of Haskell software, Haskell infrastructure, books and tutorials on Haskell. Reports on past and upcoming events related to Haskell are also relevant. Finally, there might be new topics we do not even think about. As a rule of thumb: if in doubt, then it probably is relevant and has a place in the HCAR. You can also ask the editor. Q: Is unfinished work relevant? Are ideas for projects relevant? A: Yes! You can use the HCAR to talk about projects you are currently working on. You can use it to look for other developers that might help you. You can use it to write "wishlist" items for libraries and language features you would like to see implemented. Q: If I do not update my entry, but want to keep it in the report, what should I do? A: Tell the editor that there are no changes. The old entry will typically be reused in this case, but it might be dropped if it is older than a year, to give more room and more attention to projects that change a lot. Do not resend complete entries if you have not changed them.

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CFP: Term and Graph Rewriting/TERMGRAPH 2011
by Rachid Echahed 25 Oct '10

25 Oct '10

Apologies for multiple copies ------------------------------------------------------------------------- CALL FOR PAPERS TERMGRAPH 2011 6th International Workshop on Computing with Terms and Graphs a Satellite Event of ETAPS 2011 Saarbrücken, Germany, April 2nd, 2011 http://termgraph2011.imag.fr http://www.termgraph.org.uk/ Full versions of best papers will be included in an issue of the international journal Mathematical Structures in Computer Science (MSCS) -------------------------------------------------------------------------- TERMGRAPH 2011 is a one-day satellite event of ETAPS 2011 <http://www.etaps.org/>, which will take place in Saarbrücken, Germany, from March 26 to April 3rd, 2011. Previous editions of the TERMGRAPH workshops series (http://www.termgraph.org.uk/) took place in Barcelona (2002), in Rome (2004), in Vienna (2006), in Braga (2007) and in York (2009). Aims and scope Research in term and graph rewriting ranges from theoretical questions to practical issues. Computing with graphs handles the sharing of common subexpressions in a natural and seamless way, and improves the efficiency of computations in space and time. Sharing is ubiquitous in several research areas, for instance : the modelling of first- and higher-order term rewriting by (acyclic or cyclic) graph rewriting, the modelling of biological or chemical abstract machines, the implementation techniques of programming languages: many implementations of functional, logic, object-oriented, concurrent and mobile calculi are based on term graphs. Term graphs are also used in automated theorem proving and symbolic computation systems working on shared structures. The aim of this workshop is to bring together researchers working in different domains on term and graph transformation and to foster their interaction, to provide a forum for presenting new ideas and work in progress, and to enable newcomers to learn about current activities in term graph rewriting. -------------------------------------------------------------------------- Topics of Interest Topics of interest are open and include all aspects of term graphs and sharing of common subexpressions in rewriting, programming, automated reasoning and symbolic computation. This includes (but is not limited to): term rewriting, graph transformation, programming languages, models of computation, graph-based languages, semantics and implementation of programming languages, compiler construction, pattern recognition, databases, bioinformatics, and system descriptions. -------------------------------------------------------------------------- Submissions and Publication Authors are invited to submit either regular papers (up to 15 pages), or position papers, system descriptions, work in progress, extended abstracts (5-7 pages), via the EasyChair system, at URL http://www.easychair.org/conferences/?conf=termgraph2011 Submissions should be in PostScript or PDF format, using the EPTCS style files (http://style.eptcs.org/) Preliminary proceedings will be distributed at the workshop. Selected authors will be invited to submit a full version of their papers after the workshop. These submissions will pass through a second round of reviewing and accepted contributions are to be published as a special issue of the international journal Mathematical Structures in Computer Science (MSCS). -------------------------------------------------------------------------- Important Dates December 8, 2010 Abstract submission December 15, 2010 Paper submission January 16, 2011 Notification of acceptance February 4, 2011 Pre-proceedings version due -------------------------------------------------------------------------- Programme Committee Paolo Baldan, University of Padova, Italy Andrea Corradini, University of Pisa, Italy Frank Drewes, Umea University, Sweden Rachid Echahed (chair), CNRS, LIG Laboratory, France Tetsuo Ida, University of Tsukuba, Japan Wolfram Kahl, McMaster University, Canada Ian Mackie, Ecole Polytechnique, France Detlef Plump, University of York, UK -------------------------------------------------------------------------- Contact Rachid Echahed, LIG Lab., Grenoble, France echahed(a)imag.fr --------------------------------------------------------------------------

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ANNOUNCE: iteratee-compress 0.1.1
by Maciej Piechotka 24 Oct '10

24 Oct '10

Iteratee-compress provides compressing and decompressing enumerators including flushing. Currently only gzip is provided but at least bzip is planned. Changes from previous version: - Independent from zlib library (Haskell one, not C) - Allow hand-flushing the contents (from outside). - Fix potential memory-leak Next goals: - BZip support - Generic interface for flushing To think about: - Should inner iteratee be able to request flushing? Regards PS. It did change API by removing dependency on zlib but I home such breakage in 0.1.x will be allowed

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Haskell Weekly News: Issue 155 - October 20, 2010 (Originally posted to Haskell-Cafe)
by Daniel Santa Cruz 24 Oct '10

24 Oct '10

Hello all, Malcolm Wallace noticed that I had not posted the HWN to this list, and requested that I do so. I realize that many of you are also following -Cafe, and I do apologize if this is a bit spamish due to that. Hopefully some of you will find this useful. -Daniel Welcome to issue 155 of the HWN, a newsletter covering developments in the [1]Haskell community in the week of October 10 - 16. This time around we again have 87 posts to HackageDB. Instead of posting the individual packages, we get to see and celebrate the 43 people behind these efforts. Want to keep a close eye on the haskellers that lurk twitter? Don Steward made [2]a twitter list of tweeting haskellers! Let him know if you'd like to be added to the list. There were a total of 24 new stories posted to the Haskell Reddit channel, 27 new questions taged with Haskell in StackOverflow, and 408 messages posted to Haskell-Cafe. So, what was hot last week? Announcements Gregory Crosswhite is pleased to [3]announce the release of a family of packages for type-level natural numbers. He also [4]announced tagged-list, a package which provides fixed-length lists that are tagged with a phantom type-level natural number corresponding to the length. Janis Voigtlander [5]announced that it is time to collect contributions for the 19th edition of the Haskell Communities & Activities Report. The submission deadline is November 1, 2010. Alexander Solla [6]announced his new "Facts" library. The Facts hierarchy is meant to contain commonly used, relatively static facts about the "real world." Kevin Jardine [7]announced polyToMonoid: a library that supplies two very general polyvariadic functions that can map their arguments into any monoid you specify. Simon Hengel [8]announced a new version of DocTest. DocTest now uses Haddock for parsing of comments. Interesting Threads on Haskell-Cafe Michael Snoyman [9]reported that Haskellers.com has become popular a lot falter that he anticipated. Read up on what changes are planned for Haskellers.com. Michael is very interested in some help with running the site. Jacek Generowicz [10]asked how to deal with dynamic dispatch on extensible sets of types. Uwe Schmidt [11]replied to a question about why HXT uses arrows as opposed to using monads. Good comments followed. Jason Dusek [12]asked if there is a way to write a Haskell data structure that is necessarily only one or two or seventeen items long; but that is nonetheless statically guaranteed to be of finite length? Twenty-three messages followed. Simon Thompson [13]annouced the availability of books for review for the Journal of Functonial Programming. Andrew Copping [14]summarized a report produced by Google Szwitzerland on taking a Python system and rewriting bits of it in Haskell, some of which is now in production use. Ben Franksen [15]ranted about the current "Haskell Blurb" on the first paragraph of haskell.org. Quite the read to end the week :) Top Reddit Stories * Using Haskell’s ‘newtype’ in C Domain: blog.nelhage.com Score: 37, Comments: 5 On Reddit: http://www.reddit.com/r/haskell/comments/dptzh/using_haskells_newtype_in_c/ Original: http://blog.nelhage.com/2010/10/using-haskells-newtype-in-c/ * The Haskell theme: consistent visual branding for Haskell Domain: haskell.org Score: 34, Comments: 11 On Reddit: http://www.reddit.com/r/haskell/comments/dqiej/the_haskell_theme_consistent… Original: http://www.haskell.org/pipermail/haskell-cafe/2010-October/084781.html * Haskellers: Survey results and new site features Domain: haskellers.com Score: 22, Comments: 6 On Reddit: http://www.reddit.com/r/haskell/comments/dr37b/haskellers_survey_results_an… Original: http://www.haskellers.com/news/1/ * My Experience Learning Haskell Domain: blog.virtucal.com Score: 21, Comments: 6 On Reddit: http://www.reddit.com/r/haskell/comments/drgcz/my_experience_learning_haske… Original: http://blog.virtucal.com/cyclical/2010/10/14/my-experience-learning-haskell… * Invertible monads for exception handling and memory allocations Domain: docs.yesodweb.com Score: 21, Comments: 0 On Reddit: http://www.reddit.com/r/haskell/comments/drkdj/invertible_monads_for_except… Original: http://docs.yesodweb.com/blog/invertible-monads-exceptions-allocations/ * Accelerating Haskell Array Codes with Multicore GPUs Domain: justtesting.org Score: 19, Comments: 0 On Reddit: http://www.reddit.com/r/haskell/comments/dq1yo/accelerating_haskell_array_c… Original: http://justtesting.org/accelerating-haskell-array-codes-with-multico * Unicode text performance improvements Domain: serpentine.com Score: 17, Comments: 1 On Reddit: http://www.reddit.com/r/haskell/comments/drinz/unicode_text_performance_imp… Original: http://www.serpentine.com/blog/2010/10/15/unicode-text-performance-improvem… * Like a coding challenge? Check out Code Quarterly! Domain: serpentine.com Score: 16, Comments: 9 On Reddit: http://www.reddit.com/r/haskell/comments/dpjgv/like_a_coding_challenge_chec… Original: http://www.serpentine.com/blog/2010/10/11/like-a-coding-challenge-check-out… * C9 Lecture: Ralf Lämmel on Monads Domain: channel9.msdn.com Score: 16, Comments: 0 On Reddit: http://www.reddit.com/r/haskell/comments/dq614/c9_lecture_ralf_lämmel_on_mo… Original: http://channel9.msdn.com/Shows/Going+Deep/C9-Lectures-Dr-Ralf-Lmmel-AFP-The… * Take the Haskellers.com survey Domain: spreadsheets.google.com Score: 15, Comments: 3 On Reddit: http://www.reddit.com/r/haskell/comments/dq7xj/take_the_haskellerscom_surve… Original: https://spreadsheets.google.com/viewform?formkey=dG8tcVhBdzRSS1lkdVV6U281em… Top StackOverflow Questions * When is memoization automatic in GHC Haskell? Question (votes: 14, answers: 3) http://stackoverflow.com/questions/3951012/when-is-memoization-automatic-in… * Why is my code using monadic lists from the List package so slow? Question (votes: 12, answers: 3) http://stackoverflow.com/questions/3916444/why-is-my-code-using-monadic-lis… * Haskell: lift vs liftIO Question (votes: 8, answers: 2) http://stackoverflow.com/questions/3921237/haskell-lift-vs-liftio * Can anyone suggest a good constraint library for Haskell? Question (votes: 8, answers: 2) http://stackoverflow.com/questions/3926656/can-anyone-suggest-a-good-constr… * Library function to compose a function with itself n times Question (votes: 6, answers: 4) http://stackoverflow.com/questions/3911060/library-function-to-compose-a-fu… * Evaluation of a small math type language that supports one variable Question (votes: 5, answers: 1) http://stackoverflow.com/questions/3906231/evaluation-of-a-small-math-type-… * What's the difference of a “class” in Haskell and in an “abstract class” in OO language? Question (votes: 5, answers: 4) http://stackoverflow.com/questions/3938779/whats-the-difference-of-a-class-… * Haskell and State Question (votes: 5, answers: 4) http://stackoverflow.com/questions/3944170/haskell-and-state * Can Haskell guard on abstract data types in a polymorphic function? Question (votes: 5, answers: 3) http://stackoverflow.com/questions/3944756/can-haskell-guard-on-abstract-da… Quotes of the Week * pumpkin: sounds like a lot of work! it's easier for me to just bitch about it * OlegKiselyov: Haskell is inconsistent in yet another way. * monochrom: just add #! /usr/bin/runghc to your haskell file. then type errors occur at runtime only. * IIcke: [haskell] is like wearing a corset, at the beginning is annoying, but then your tits look bigger and the world becomes a better place Contributors to HackageDB Who contributed, and how many uploads did they make? MichaelSnoyman (14), BryanOSullivan (11), GregoryCrosswhite (5), AndyStewart (5), GregoryCollins (4), JosePedroMagalhaes (3), StephenBlackheath (2), SjoerdVisscher (2), PaulTalaga (2), MichaelZuo (2), DanielDiaz (2), ConalElliott (2), AristidBreitkreuz (2), AlexanderSolla (2), YuriyIskra (1), VivianMcPhail (1), TristanSkudlik (1), TonyMorris (1), StephenTetley (1), SimonHengel (1), ReinierLamers (1), OlegBelozeorov (1), NeilMitchell (1), MaxBolingbroke (1), MatthiasBartsch (1), MatthewSottile (1), MasatakeDaimon (1), MarkSnyder (1), ManuelChakravarty (1), LeePike (1), KiYungAhn (1), KevinJardine (1), JustinBailey (1), IlyaPortnov (1), GeoffHulette (1), EugeneKirpichov (1), DonaldStewart (1), DanielSeidel (1), DanielSchoepe (1), CarlHowells (1), BenFranksen (1), ArieMiddelkoop (1), AlexSuraci (1) About the Haskell Weekly News New editions are posted to [16]the Haskell mailing list as well as to [17]the Haskell Sequence and [18]Planet Haskell. [19]RSS is also available, and headlines appear on [20]haskell.org. To help create new editions of this newsletter, please send stories to dstcruz * at * gmail * dot * com. The code used to produce this version of the newsletter is not yet publicly available, as it is a complete hack designed to get things started again. Until next time, Daniel Santa Cruz References 1. http://haskell.org/ 2. http://twitter.com/#!/donsbot/haskellers 3. http://groups.google.com/group/haskell-cafe/browse_thread/thread/c007154763… 4. http://groups.google.com/group/haskell-cafe/browse_thread/thread/ff95d6c78d… 5. http://groups.google.com/group/haskell-cafe/msg/d9d227b0f38bcf51 6. http://groups.google.com/group/haskell-cafe/browse_thread/thread/fc86bd03d0… 7. http://groups.google.com/group/haskell-cafe/browse_thread/thread/4ba5741441… 8. http://groups.google.com/group/haskell-cafe/browse_thread/thread/7982f0ad3b… 9. http://groups.google.com/group/haskell-cafe/browse_thread/thread/2440a1683f… 10. http://groups.google.com/group/haskell-cafe/browse_thread/thread/f0a05dd5b5… 11. http://groups.google.com/group/haskell-cafe/browse_thread/thread/38185e7ba6… 12. http://groups.google.com/group/haskell-cafe/browse_thread/thread/7ba4b3b038… 13. http://www.cs.kent.ac.uk/people/staff/sjt/JFP/available.html 14. http://groups.google.com/group/haskell-cafe/browse_thread/thread/81707fea2b… 15. http://groups.google.com/group/haskell-cafe/browse_thread/thread/a7c7b569dd… 16. http://www.haskell.org/mailman/listinfo/haskell 17. http://sequence.complete.org/ 18. http://planet.haskell.org/ 19. http://sequence.complete.org/node/feed 20. http://haskell.org/

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PostDoc and PhD Positions at Yale University
by Zhong Shao 22 Oct '10

22 Oct '10

[Apology for possible cross-postings!] The Department of Computer Science at Yale University is seeking applicants for PostDoc and PhD positions in the broad area of certified software. The successful applicants will be expected to participate in a rigorous research program on topics such as programming languages, formal semantics, certified operating systems, program verification, proof assistants and automation, concurrency and coordination, language-based security, and certifying compilers. The programming languages and operating systems group, led jointly by Professors Zhong Shao and Bryan Ford at Yale, is embarking on a multi-year effort to develop a new certified OS kernel that generalizes and unifies traditional OS abstractions in microkernels and hypervisors. The new effort advocates a modular certification framework for OS kernel components, which mirrors and enhances the modularity of the kernel itself. Using this framework, it aims to create not just a "one-off" lump of verified kernel code, but a statically and dynamically extensible kernel that can be incrementally built and extended with individual certified modules, each of which will provably preserve the kernel's overall safety and security properties. Important research questions include but are not limited to: what OS kernel structures can offer the best support for extensibility, security, and resilience? what program logics and semantic models can best capture these abstractions? what are the right programming languages and environments for developing such certified kernel? and how to build new automation facilities to make certified software really scale? Successful applicants should have a combination of creativity, self-motivation, and strong interests on applying programming language theory or formal methods to solve practical problems. Applicants for PostDoc positions must have a Ph.D. in Computer Science or a closely related field. The term of a PostDoc position is one year with an option to renew for up to four years. Starting date is negotiable (a preference will be given to those who can start by Spring 2011). Interested applicants for PostDoc positions should email a CV, research statement, and the names of three references with their email addresses and phone numbers to Zhong Shao (Email: zhong.shao at yale.edu) PhD positions (with full guaranteed financial support) are also available. Applicants interested in pursuing PhD studies can email either PI but should still submit their applications directly to the Yale Graduate School of Arts and Sciences (the deadline for Fall 2011 admission is January 2nd, 2011). More information regarding this research effort can be found in a white paper available at <http://flint.cs.yale.edu/ctos> or at the two PIs' research web sites <http://flint.cs.yale.edu> and <http://dedis.cs.yale.edu>. Inquiries can be directed to any PI. Professors Zhong Shao and Bryan Ford Department of Computer Science Yale University P.O. Box 208285 New Haven, CT 06520-8285, USA Phone: +1 (203) 432 6828 and +1 (203) 432 1055 Email: zhong.shao at yale.edu and bryan.ford at yale.edu

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ICFP 2011: Call for Workshop Proposals
by Wouter Swierstra 22 Oct '10

22 Oct '10

CALL FOR WORKSHOP AND CO-LOCATED EVENT PROPOSALS ICFP 2011 16th ACM SIGPLAN International Conference on Functional Programming September 19 - 21, 2011 Tokyo, Japan http://www.icfpconference.org/icfp2011 The 16th ACM SIGPLAN International Conference on Functional Programming will be held in Tokyo, Japan on September 19-21, 2011. ICFP provides a forum for researchers and developers to hear about the latest work on the design, implementations, principles, and uses of functional programming. Proposals are invited for workshops (and other co-located events, such as tutorials) to be affiliated with ICFP 2011 and sponsored by SIGPLAN. These events should be more informal and focused than ICFP itself, include sessions that enable interaction among the attendees, and be fairly low-cost. The preference is for one-day events, but other schedules can also be considered. NEW THIS YEAR: The workshops are scheduled to occur on September 18 (the day before ICFP) and September 22-24 (the three days after ICFP). ---------------------------------------------------------------------- Submission details Deadline for submission: November 19, 2010 Notification of acceptance: December 17, 2010 Prospective organizers of workshops or other co-located events are invited to submit a completed workshop proposal form in plain text format to the ICFP 2011 workshop co-chairs (Gabriele Keller and Derek Dreyer), via email to icfp11-workshops at mpi-sws.org by November 19, 2010. (For proposals of co-located events other than workshops, please fill in the workshop proposal form and just leave blank any sections that do not apply.) Please note that this is a firm deadline. Organizers will be notified if their event proposal is accepted by December 17, 2010, and if successful, depending on the event, they will be asked to produce a final report after the event has taken place that is suitable for publication in SIGPLAN Notices. The proposal form is available at: http://www.icfpconference.org/icfp2011/icfp11-workshops-form.txt Further information about SIGPLAN sponsorship is available at: http://acm.org/sigplan/sigplan_workshop_proposal.htm ---------------------------------------------------------------------- Selection committee The proposals will be evaluated by a committee comprising the following members of the ICFP 2010 organizing committee, together with the members of the SIGPLAN executive committee. Workshop Co-Chair: Gabriele Keller (University of New South Wales) Workshop Co-Chair: Derek Dreyer (MPI-SWS) General Co-Chair: Manuel Chakravarty (University of New South Wales) General Co-Chair: Zhenjiang Hu (National Institute of Informatics) Program Chair: Olivier Danvy (Aarhus University) ---------------------------------------------------------------------- Further information Any queries should be addressed to the workshop co-chairs (Gabriele Keller and Derek Dreyer), via email to icfp11-workshops at mpi-sws.org.

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Deepseq
by Gilmara Pompelli 22 Oct '10

22 Oct '10

Hello How do I use deepseq, this function to force evaluation, the way I did is correct? um :: IO () um = do conteudo <- learquivo "mkList1.txt" mapasort <- return (mapa psort conteudo) time $ mapasort `deepseq` return () Thanks

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