April 2009 - Haskell - Haskell.org

Lecturer in Computer Science, University of Leicester
by Roy L. Crole 07 Apr '09

07 Apr '09

Dear Colleagues, Please pass on details of the lectureship below. Applications specializing in algorithms, semantics or modelling are welcomed. Roy Crole. Lecturer in Computer Science Department of Computer Science University of Leicester Salary Grade 8: £35,469 to £43,622 p.a. Available from: 1 September 2009 Ref: A4140 The successful candidate will have a strong or promising research record in computer science, with a background in formal foundations (either algorithms and complexity, or semantics of programming or modelling languages), and will be able to contribute to undergraduate and postgraduate teaching and supervision in software engineering. If you wish to apply, download an application form and further information from www.le.ac.uk/personnel/jobs or contact Personnel Services on recruitment3(a)le.ac.uk. Closing Date: Friday 1 May 2009 Times Higher Education University of the Year 2008/09

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Marketing Haskell
by Simon Peyton-Jones 06 Apr '09

06 Apr '09

Dear Haskell enthusiasts, Now that the logo issue finally has been settled, it is time to select the proper Haskell mascot. As you are no doubt aware, Microsoft's involvement in Haskell means that we have moved from avoiding success at all cost to actively marketing the language, and any language striving for success is entirely dependent on a cute and distinctive mascot. Where would Perl be today without its camel? Since the recent logo discussion has demonstrated once and for all the futility of attempting a democratic process in the Haskell community - to be quite honest, the elected logo looks like an error message from an IBM mainframe - I have decided to decide on a mascot myself. So I hereby declare the official Haskell mascot to be the koala, in the form of the image attached below. Please ensure that this image accompanies any material published on the web or on paper. Simon

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Haskell Weekly News: Issue 112 - April 5, 2009
by Brent Yorgey 05 Apr '09

05 Apr '09

--------------------------------------------------------------------------- Haskell Weekly News http://sequence.complete.org/hwn/20090405 Issue 112 - April 05, 2009 --------------------------------------------------------------------------- Welcome to issue 112 of HWN, a newsletter covering developments in the [1]Haskell community. Announcements hgettext-0.1.5 - GetText based internationalization of Haskell programs. Vasyl Pasternak [2]announced a new release of the [3]hgettext package for internationalization of Haskell programs, which now supports distribution and installation of PO files. Buster 0.99.1, a library for application orchestration that is not FRP. Jeff Heard [4]announced the release of [5]Buster, an FRP-like framework for constructing reactive programs with a bus model. Call for Contributions - Haskell Communities and Activities Report, May 2009 edition. Janis Voigtlaender [6]issued a call for contributions to the 16th edition of the [7]Haskell Communities & Activities Report. The submission deadline is 1 May 2009. 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! fad 1.0 -- Forward Automatic Differentiation library. Bjorn Buckwalter [8]announced the initial release of the Haskell [9]fad library, developed by Barak A. Pearlmutter and Jeffrey Mark Siskind. Fad provides Forward Automatic Differentiation (AD) for functions polymorphic over instances of 'Num'. hledger 0.4 released. Simon Michael [10]announced the release of [11]hledger 0.4, a text-mode double-entry accounting tool. It reads a plain text journal file describing your transactions and generates precise activity and balance reports. Changes include the ability to serve reports in a web browser, and many other fixes and improvements. GHC version 6.10.2. Ian Lynagh [12]announced a new patchlevel release of [13]GHC. This release contains a number of bugfixes relative to 6.10.1, including some performance fixes; see the [14]release notes. Beta of Leksah IDE available. Jürgen Nicklisch-Franken [15]announced release 0.4.4 of [16]Leksah, the Haskell IDE written in Haskell. Current features include on the fly error reporting with location of compilation errors, completion , import helper for constructing import statements, module browser with navigation to definition, project management support based on Cabal with a visual editor, "source candy", and more. satchmo: monadic SAT encoding library. Johannes Waldmann [17]announced a preliminary version of [18]satchmo, a monadic library for encoding boolean and integral number constraints to CNF-SAT. It uses [19]minisat as a backend solver. vacuum-cairo: a cairo frontend to vacuum for live Haskell data visualization. Don Stewart [20]announced the release of [21]vacuum-cairo, a Haskell library for interactive rendering and display of values on the GHC heap using Matt Morrow's vacuum library. This library takes vacuum's output, generates dot graph format from it, renders it to SVG with graphviz, and displays the resulting structure using the gtk2hs Cairo vector graphics bindings ... all at the GHCi command line. Watch some [22]screencasts! vacuum: extract graph representations of ghc heap values.. Matt Morrow [23]announced the release of [24]vacuum, a library for extracting graph representations of values from the GHC heap, which may then be further processed and/or translated to Graphviz dot format to be visualized. new release of HTTP, version 4000.0.5. Sigbjorn Finne [25]announced a [26]new version of the HTTP package, which includes a bunch of fixes and cleanups along with some API documentation. type-level programming support library. spoon [27]asked for feedback on a [28]support library for type level programming. cmonad 0.1.1. Lennart Augustsson [29]announced the [30]CMonad package, which allows one to write Haskell code in a C style. Marketing Haskell. Ketil "Simon Peyton-Jones" Malde [31]announced the new [32]official Haskell mascot. Haskell Platform: status update and call for volunteers. Duncan Coutts gave an [33]update on the status of the [34]Haskell Platform. There are no more policy questions to resolve for the first release. It is a matter of getting things done. The first platform release will contain ghc-6.10.2, the "extra libs", haddock, happy and alex, and the cabal command line tool and it's dependencies. We are calling for volunteers for an action group. We need volunteers to take charge of various platforms and to manage the overall release. See Duncan's email for a list of what is needed, and volunteer! Blog noise [35]Haskell news from the [36]blogosphere. * Jeff Heard: [37]Major updates to Buster. * Bjorn Buckwalter: [38]ANNOUNCE: fad 1.0---Forward Automatic Differentiation for Haskell. * Roman Cheplyaka: [39]Hpysics + GrapeFruit (and hackathon). * Joachim Breitner: [40]Bejeweled AI in Haskell. * >>> iampalmmute: [41]Vacuum + Ubigraph. Visualizing Haskell values in 3D. * Jeff Heard: [42]ANN: Buster, the not quite entirely unlike FRP library.. * Edward Kmett: [43]Reflecting On Incremental Folds. * beelsebob: [44]How you should(n't) use Monad. * Sean Leather: [45]Incremental attributes. * Jeff Heard: [46]Almost, but not quite entirely unlike FRP.. * >>> Gregory Collins: [47]Building a website with Haskell, part 2. * >>> Rubin Mcgowan: [48]Irradiation Tracing in Haskell. * Conal Elliott: [49]Notions of purity in Haskell. * mightybyte: [50]Finished HAppS Application. * Sean Leather: [51]Experiments with EMGM: Emacs org files. * Yi: [52]Haddock is back. * >>> Lab 49: [53]Does Haskell Support Subtyping? It Depends.. * >>> Tim Lopez: [54]Haskell Performance: Lowercase. * >>> Gregory Collins: [55]Building a website with Haskell, part 1. * happstack.com: [56]Happstack-powered Website launched by Gregory David Collins. * >>> LispCast: [57]Writing map in Haskell. * >>> hellfeuer: [58]Laziness and Dynamic Programming. * >>> Leon Smith: [59]Lloyd Allison's Corecursive Queues. Quotes of the Week * mstr: haskell is like f'gg'fggf'fg'g'fg'foldliftM2 f g ''f' :) * simonmar: Wondering how popular Haskell needs to become for intel to optimize their processors for my runtime, rather than the other way around * quicksilver: [about uninstalling packages installed with cabal-install] packages are for life, not just for christmas. * Ethereal: If this conversation had been had in #python #ruby or #php it would have lots of angry people shouting about how it doesn't matter or isn't true or isn't important and what's the point, and no, you guys are like ahhh but no, your preconceived notions of dimensional space are so passe. * Duqicnk: a monad is like a train that runs backwards in time, which is made of tiny chocolate robots * jfredett: I do all of my version numbers in Roman Numerals... * Cale: But in another sense, functional programmers are applied logicians who spend all their time proving trivial theorems in interesting ways in an inconsistent intuitionist logic. About the Haskell Weekly News New editions are posted to [60]the Haskell mailing list as well as to [61]the Haskell Sequence and [62]Planet Haskell. [63]RSS is also available, and headlines appear on [64]haskell.org. To help create new editions of this newsletter, please see the information on [65]how to contribute. Send stories to byorgey at cis dot upenn dot edu. The darcs repository is available at darcs get [66]http://code.haskell.org/~byorgey/code/hwn/ . References 1. http://haskell.org/ 2. http://article.gmane.org/gmane.comp.lang.haskell.cafe/56301 3. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/hgettext 4. http://article.gmane.org/gmane.comp.lang.haskell.cafe/56209 5. http://vis.renci.org/jeff/buster 6. http://article.gmane.org/gmane.comp.lang.haskell.cafe/56148 7. http://www.haskell.org/communities/ 8. http://article.gmane.org/gmane.comp.lang.haskell.cafe/56268 9. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/fad 10. http://article.gmane.org/gmane.comp.lang.haskell.general/17054 11. http://hledger.org/ 12. http://article.gmane.org/gmane.comp.lang.haskell.general/17041 13. http://www.haskell.org/ghc/ 14. http://haskell.org/ghc/docs/6.10.2/html/users_guide/release-6-10-2.html 15. http://article.gmane.org/gmane.comp.lang.haskell.cafe/56116 16. http://www.leksah.org/ 17. http://article.gmane.org/gmane.comp.lang.haskell.cafe/56107 18. http://dfa.imn.htwk-leipzig.de/satchmo/ 19. http://minisat.se/ 20. http://article.gmane.org/gmane.comp.lang.haskell.cafe/56063 21. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/vacuum-cairo 22. http://www.youtube.com/watch?v=oujaqo9GAmA 23. http://article.gmane.org/gmane.comp.lang.haskell.cafe/56062 24. http://moonpatio.com/vacuum/ 25. http://article.gmane.org/gmane.comp.lang.haskell.cafe/56058 26. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/HTTP 27. http://article.gmane.org/gmane.comp.lang.haskell.cafe/55983 28. http://www.killersmurf.com/projects/typelib 29. http://article.gmane.org/gmane.comp.lang.haskell.cafe/55936 30. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/cmonad 31. http://article.gmane.org/gmane.comp.lang.haskell.general/17021 32. http://www.haskell.org/pipermail/haskell/attachments/20090401/9fb8fa05/hask… 33. http://article.gmane.org/gmane.comp.lang.haskell.general/17020 34. http://www.haskell.org/haskellwiki/Haskell_Platform 35. http://planet.haskell.org/ 36. http://haskell.org/haskellwiki/Blog_articles 37. http://vis.renci.org/jeff/2009/04/03/major-updates-to-buster/ 38. http://flygdynamikern.blogspot.com/2009/04/announce-fad-10-forward-automati… 39. http://physics-dph.blogspot.com/2009/04/hpysics-grapefruit-and-hackathon.ht… 40. https://www.joachim-breitner.de/blog/archives/324-Bejeweled-AI-in-Haskell.h… 41. http://www.youtube.com/watch?v=3mMH1cHWB6c 42. http://vis.renci.org/jeff/2009/04/01/ann-buster-the-not-quite-entirely-unli… 43. http://comonad.com/reader/2009/incremental-folds/ 44. http://noordering.wordpress.com/2009/03/31/how-you-shouldnt-use-monad/ 45. http://feedproxy.google.com/~r/splonderzoek/~3/4B0bHoeTCeQ/incremental-attr… 46. http://vis.renci.org/jeff/2009/03/31/almost-but-not-quite-entirely-like-frp/ 47. http://gregorycollins.net/posts/2009/03/30/building-a-website-part-2 48. http://rubinmcgowaneh.blogspot.com/2009/03/irradiation-tracing-in-haskell.h… 49. http://conal.net/blog/posts/notions-of-purity-in-haskell/ 50. http://softwaresimply.blogspot.com/2008/02/finished-happs-application.html 51. http://feedproxy.google.com/~r/splonderzoek/~3/6bxI33NIRMc/experiments-with… 52. http://yi-editor.blogspot.com/2009/03/haddock-is-back.html 53. http://blog.lab49.com/archives/2954 54. http://www.brool.com/index.php/haskell-performance-lowercase 55. http://gregorycollins.net/posts/2009/03/28/building-a-website-part-1 56. http://blog.happstack.com/2009/03/28/happstack-powered-website-launched-by-… 57. http://www.lispcast.com/haskell-map.html 58. http://caffeinatedcode.wordpress.com/2009/03/26/laziness-and-dynamic-progra… 59. http://blog.melding-monads.com/2009/03/09/lloyd-allisons-corecursive-queues/ 60. http://www.haskell.org/mailman/listinfo/haskell 61. http://sequence.complete.org/ 62. http://planet.haskell.org/ 63. http://sequence.complete.org/node/feed 64. http://haskell.org/ 65. http://haskell.org/haskellwiki/HWN 66. http://code.haskell.org/~byorgey/code/hwn/

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TFM09: Call for Papers (Formal Methods Week, Eindhoven, November 6th 2009)
by J.N. Oliveira 03 Apr '09

03 Apr '09

TFM2009 2nd Int. FME Conference on Teaching Formal Methods "Widening Access to Formal Methods" Friday, November 6th 2009 co-located with FM2009 : 16th International Symposium on Formal Methods Eindhoven, the Netherlands, November 2 - November 6, 2009 CALL FOR PAPERS (URL: http://www.di.uminho.pt/tfm09) 1. About the conference ----------------------- Ten years after the First World Formal Methods Congress (FM'99) in Toulouse, formal methods communities from all over the world will once again have an opportunity to come together. As part of the First Formal Methods Week event surrounding the FM2009 conference in Eindhoven, Formal Methods Europe will be organizing TFM2009, the Second International Conference on Teaching Formal Methods. The conference will serve as a forum to explore the successes and failures of Formal Methods (FM) education, and to promote cooperative projects to further education and training in FMs. We would like to provide a forum for lecturers, teachers, and industrial partners to discuss their experience, present their pedagogical methodologies, and explore best practices. TFM2009 follows in a series of recent events on teaching formal methods, including: two BCS-FACS TFM workshops (Oxford in 2003, and London in 2006), the TFM 2004 conference in Ghent (with proceedings published as Springer LNCS Volume 3294), the FM-Ed 2006 workshop (Hamilton, co-located with FM'06), FORMED (Budapest, at ETAPS 2008), FMET 2008 (Kitakyushu 2008, co-located with ICFEM), etc. 2. Topics of interest --------------------- Formal methods (FM) have an important role to play in the development of complex computing systems - a role acknowledged in industrial standards such as IEC 61508 and ISO/IEC 15408, and in the increasing use of precise modeling notations, semantic markup languages, and model-driven techniques. There is a growing need for software engineers who can work effectively with simple, mathematical abstractions, and with practical notions of inference and proof. However, there is little clear guidance ? for educators, for managers, or for the engineers themselves ? as to what might comprise a basic education in FM. Neither the present IEEE/ACM Software Engineering Body of Knowledge (SWEBOK) nor the forthcoming Graduate Software Engineering Reference Curriculum (GSWERC) provide the kind of specific information that teachers and practitioners need to establish an adequate, balanced programme of learning in FM. Original contributions are solicited that provide insight, opinions, and suggestions for courses of action regarding the teaching FMs, including but not limited to the following aspects: * experiences of teaching FMs, both successful and unsuccessful; * educational resources including the use of books, case studies and the internet; * the education of weak and mathphobic students; * the integration, or otherwise, of FMs into the curriculum, including contributions to the definition of a Formal Methods Body of Knowledge (FMBOK); * the advantages of FM-trained graduates in the workplace; * changing attitudes towards FMs in students, academic staff and practitioners; * the necessary mathematical background. Submissions may be up to 20 pages long, using the Springer LNCS format. Negotiations are under way with Springer Verlag for the publication of the proceedings of the conference in the LNCS series. 3. Important dates ------------------ Please put the following dates in your diary: Submission deadline May 25, 2009 Notification of acceptance July 6, 2009 Final version August 3, 2009 4. Invited speakers ------------------- To be announced 5. Programme Committee ---------------------- Izzat Alsmadi (North Dakota State University, USA) Dines Bjorner (IIMM Institute, Denmark) Eerke Boiten (University of Kent, UK) Raymond Boute (Universiteit Gent, Belgium) Andrew Butterfield (Trinity College, Dublin) Jim Davies (University of Oxford, UK) David Duce (Oxford Brookes University, UK) John Fitzgerald (University of Newcastle upon Tyne, UK) Jeremy Gibbons (University of Oxford, UK) Randolph Johnson (National Security Agency, USA) Michael Mac an Airchinnigh (Trinity College, Dublin) Dino Mandrioli (Politecnico di Milano, Italy) Jose Oliveira (Universidade do Minho, Portugal) Kees Pronk (Technische Universiteit Delft, NL) Bernhard Schaetz (Tecnical University of Munique, Germany) Wolfgang Schreiner (Johannes Kepler University Linz, Austria) Simao Melo de Sousa (Universidade da Beira Interior, Portugal) Kenji Taguchi (National Institute of Informatics, Japan) Jeannette Wing (Carnegie-Mellon University, USA)

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Re: [Haskell-cafe] ANNOUNCE: fad 1.0 -- Forward Automatic Differentiation library
by Edward Kmett 03 Apr '09

03 Apr '09

A somewhat tricky concern is that that the extra functionality in question depends on a bunch of primitive definitions that lie below this in the package and the AD engine is used by a layer on top. So moving it out would introduce a circular dependency back into the package or require me to stratify into two packages. When I looked into partitioning the package for another reason I found that I couldn't do so without introducing some orphan instances, so it'll probably be a tricky bit of surgery to split out. That said, it's probably still worth doing. I also agree that I should be somewhat more pedantic about the name. =) -Edward Kmett On Fri, Apr 3, 2009 at 10:49 AM, Barak A. Pearlmutter <barak(a)cs.nuim.ie>wrote: > I feel silly, did not even notice that! Thanks for the pointer. > > Would be sensible to merge the functionalities; will try to import > functionality in Data.Ring.Module.AutomaticDifferentiation currently > missing from Numeric.FAD. > > (One pedantic note: should really be named > Data.Ring.Module.AutomaticDifferentiation.Forward, since it is doing > forward-mode accumulation automatic differentiation; reverse is > an adjoint kettle of fish.) > -- > Barak A. Pearlmutter > Hamilton Institute & Dept Comp Sci, NUI Maynooth, Co. Kildare, Ireland > http://www.bcl.hamilton.ie/~barak/ >

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ANNOUNCE: fad 1.0 -- Forward Automatic Differentiation library
by Bjorn Buckwalter 03 Apr '09

03 Apr '09

I'm pleased to announce the initial release of the Haskell fad library, developed by Barak A. Pearlmutter and Jeffrey Mark Siskind. Fad provides Forward Automatic Differentiation (AD) for functions polymorphic over instances of 'Num'. There have been many Haskell implementations of forward AD, with varying levels of completeness, published in papers and blog posts[1], but alarmingly few of these have made it into hackage -- to date Conal Elliot's vector-spaces[2] package is the only one I am aware of. Fad is an attempt to make as comprehensive and usable a forward AD package as is possible in Haskell. However, correctness is given priority over ease of use, and this is in my opinion the defining quality of fad. Specifically, Fad leverages Haskell's expressive type system to tackle the problem of _perturbation confusion_, brought to light in Pearlmutter and Siskind's 2005 paper "Perturbation Confusion and Referential Transparency"[3]. Fad prevents perturbation confusion by employing type-level "branding" as proposed by myself in a 2007 post to haskell-cafe[4]. To the best of our knowledge all other forward AD implementations in Haskell are susceptible to perturbation confusion. As this library has been in the works for quite some time it is worth noting that it hasn't benefited from Conal's ground-breaking work[5] in the area. Once we wrap our heads around his beautiful constructs perhaps we'll be able to borrow some tricks from him. As mentioned already, fad was developed primarily by Barak A. Pearlmutter and Jeffrey Mark Siskind. My own contribution has been providing Haskell infrastructure support and wrapping up loose ends in order to get the library into a releasable state. Many thanks to Barak and Jeffrey for permitting me to release fad under the BSD license. Fad resides on GitHub[6] and hackage[7] and is only a "cabal install fad" away! What follows is Fad's README, refer to the haddocks for detailed documentation. Thanks, Bjorn Buckwalter [1] http://www.haskell.org/haskellwiki/Functional_differentiation [2] http://www.haskell.org/haskellwiki/Vector-space [3]: http://www.bcl.hamilton.ie/~qobi/nesting/papers/ifl2005.pdf [4]: http://thread.gmane.org/gmane.comp.lang.haskell.cafe/22308/ [5]: http://conal.net/papers/beautiful-differentiation/ [6] http://github.com/bjornbm/fad/ [7] http://hackage.haskell.org/cgi-bin/hackage-scripts/package/fad ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Copyright : 2008-2009, Barak A. Pearlmutter and Jeffrey Mark Siskind License : BSD3 Maintainer : bjorn.buckwalter(a)gmail.com Stability : experimental Portability: GHC only? Forward Automatic Differentiation via overloading to perform nonstandard interpretation that replaces original numeric type with corresponding generalized dual number type. Each invocation of the differentiation function introduces a distinct perturbation, which requires a distinct dual number type. In order to prevent these from being confused, tagging, called branding in the Haskell community, is used. This seems to prevent perturbation confusion, although it would be nice to have an actual proof of this. The technique does require adding invocations of lift at appropriate places when nesting is present. For more information on perturbation confusion and the solution employed in this library see: <http://www.bcl.hamilton.ie/~barak/papers/ifl2005.pdf> <http://thread.gmane.org/gmane.comp.lang.haskell.cafe/22308/> Installation ============ To install: cabal install Or: runhaskell Setup.lhs configure runhaskell Setup.lhs build runhaskell Setup.lhs install Examples ======== Define an example function 'f': > import Numeric.FAD > f x = 6 - 5 * x + x ^ 2 -- Our example function Basic usage of the differentiation operator: > y = f 2 -- f(2) = 0 > y' = diff f 2 -- First derivative f'(2) = -1 > y'' = diff (diff f) 2 -- Second derivative f''(2) = 2 List of derivatives: > ys = take 3 $ diffs f 2 -- [0, -1, 2] Example optimization method; find a zero using Newton's method: > y_newton1 = zeroNewton f 0 -- converges to first zero at 2.0. > y_newton2 = zeroNewton f 10 -- converges to second zero at 3.0. Credits ======= Authors: Copyright 2008, Barak A. Pearlmutter <barak(a)cs.nuim.ie> & Jeffrey Mark Siskind <qobi(a)purdue.edu> Work started as stripped-down version of higher-order tower code published by Jerzy Karczmarczuk <jerzy.karczmarczuk(a)info.unicaen.fr> which used a non-standard standard prelude. Initial perturbation-confusing code is a modified version of <http://cdsmith.wordpress.com/2007/11/29/some-playing-with-derivatives/> Tag trick, called "branding" in the Haskell community, from Bjorn Buckwalter <bjorn.buckwalter(a)gmail.com> <http://thread.gmane.org/gmane.comp.lang.haskell.cafe/22308/> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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ANN: hledger 0.4 released
by Simon Michael 03 Apr '09

03 Apr '09

Dear all, I have released hledger 0.4 on hackage. There is also a new website at http://hledger.org , with screenshots (textual!), a demo (will it survive!?), and docs (not too many!) Release notes are at http://hledger.org/NEWS , and bravely pasted below. In case you forgot: hledger is a text-mode double-entry accounting tool. It reads a plain text journal file describing your transactions and generates precise activity and balance reports. I use it every day to track money and time, and as the basis for client invoices and tax returns. hledger is a partial clone, in haskell, of John Wiegley's excellent ledger. I wrote it because I did not want to hack on c++ and because haskell seemed a good fit. Please cabal update and cabal install hledger and give it a whirl. Install with the "-f happs" flag to enable the new happstack-based web interface. I am sm on the #ledger channel on freenode, and I welcome your feedback, especially if you notice a problem. Best - Simon ------------------------------------------------- 2009/04/03 hledger 0.4 released Changes: * new "web" command serves reports in a web browser (install with -f happs to build this) * make the vty-based curses ui a cabal build option, which will be ignored on MS windows * drop the --options-anywhere flag, that is now the default * patterns now use not: and desc: prefixes instead of ^ and ^^ * patterns are now case-insensitive, like ledger * !include directives are now relative to the including file (Tim Docker) * "Y2009" default year directives are now supported, allowing m/d dates in ledger * individual transactions now have a cleared status * unbalanced entries now cause a proper warning * balance report now passes all ledger compatibility tests * balance report now shows subtotals by default, like ledger 3 * balance report shows the final zero total when -E is used * balance report hides the final total when --no-total is used * --depth affects print and register reports (aggregating with a reporting interval, filtering otherwise) * register report sorts transactions by date * register report shows zero-amount transactions when -E is used * provide more convenient timelog querying when invoked as "hours" * multi-day timelog sessions are split at midnight * unterminated timelog sessions are now counted. Accurate time reports at last! * the test command gives better --verbose output * --version gives more detailed version numbers including patchlevel for dev builds * new make targets include: ghci, haddocktest, doctest, unittest, view-api-docs * a doctest-style framework for functional/shell tests has been added * performance has decreased slightly: || hledger-0.3 | hledger-0.4 | ledger-0.3 ==============================++========== -f sample.ledger balance || 0.02 | 0.01 | 0.07 -f sample1000.ledger balance || 1.02 | 1.39 | 0.53 -f sample10000.ledger balance || 12.72 | 14.97 | 4.63 Contributors: * Simon Michael * Tim Docker * HAppS, happstack and testpack developers Stats: * Known errors: 0 * Commits: 132 * Committers: 2 * Tests: 56 * Non-test code lines: 2600 * Days since release: 75

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GTTSE 2009: 2nd call for participation (06-11 July) (registration open)
by João Saraiva 03 Apr '09

03 Apr '09

GTTSE 2009, 06-11 July, 2009, Braga, Portugal 3rd International Summer School on Generative and Transformational Techniques in Software Engineering http://gttse.wikidot.com/ *** Registration is now open *** *** Early Registration Deadline: April 24, 2009 *** SCOPE AND FORMAT The summer school brings together PhD students, lecturers, technology presenters, as well as other researchers and practitioners who are interested in the generation and the transformation of programs, data, models, meta-models, and documentation. This concerns many areas of software engineering: software reverse and re-engineering, model-driven approaches, automated software engineering, generic language technology, to name a few. These areas differ with regard to the specific sorts of meta-models (or grammars, schemas, formats etc.) that underlie the involved artifacts, and with regard to the specific techniques that are employed for the generation and the transformation of the artifacts. The tutorials are given by renowned representatives of complementary approaches and problem domains. Each tutorial combines foundations, methods, examples, and tool support. The program of the summer school also features invited technology presentations, which present setups for generative and transformational techniques. These presentations complement each other in terms of the chosen application domains, case studies, and the underlying concepts. The program of the school also features a participants workshop. All summer school material will be collected in proceedings that are handed out to the participants. Formal proceedings will be compiled after the summer school, where all contributions are subjected to additional reviewing. The formal proceedings of the previous two instances of the summer school (2005 and 2007) were published as volumes 4143 and 5235 in the Lecture Notes in Computer Science series of Springer-Verlag. TUTORIALS * Software Product Line Refactoring Paulo Borba, Universidade Federal de Pernambuco, Recife, Brazil * The TXL Source Transformation Cookbook James R. Cordy, Queen's University, Kingston, Canada * Chasing Diagrams in the Mapping Forests of Model Transformations Zinovy Diskin, University of Waterloo and Univ. of Toronto, Canada * Generating Language Tools with JastAdd Görel Hedin, Lund Institute of Technology, Sweden. * Model Driven Language Engineering with Kermeta Jean-Marc Jézéquel, IRISA, Rennes, France * Rascal: Meta-programming Made Easy Paul Klint, CWI and Universiteit van Amsterdam, Netherlands * Sourcerer: Slicing and Dicing Large Amounts of Open Source Code Cristina Videira Lopes, University of California, Irvine, USA * The Theory and Practice of Modeling Language Design for Model-Based Engineering Bran Selic, Malina Software Corp., Canada ORGANIZATION COMMITTEE * João M. Fernandes (Program Co-Chair), Univ. do Minho, Portugal * Ralf Lämmel (Program Co-Chair), Univ. Koblenz-Landau, Germany * João Saraiva, Universidade do Minho, Portugal * Joost Visser, Software Improvement Group, The Netherlands ADDITIONAL INFORMATION For additional information on the program, venue, and other details of the summer school, please consult the web page: http://gttse.wikidot.com/ For remaining questions please contact gttse2009 AT di.uminho.pt.

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ANNOUNCE: GHC version 6.10.2
by Ian Lynagh 03 Apr '09

03 Apr '09

============================================================== The (Interactive) Glasgow Haskell Compiler -- version 6.10.2 ============================================================== The GHC Team is pleased to announce a new patchlevel release of GHC. This release contains a number of bugfixes relative to 6.10.1, including some performance fixes, so we recommend upgrading. Release notes are here: http://haskell.org/ghc/docs/6.10.2/html/users_guide/release-6-10-2.html How to get it ~~~~~~~~~~~~~ The easy way is to go to the web page, which should be self-explanatory: http://www.haskell.org/ghc/ We supply binary builds in the native package format for many platforms, and the source distribution is available from the same place. Packages will appear as they are built - if the package for your system isn't available yet, please try again later. Background ~~~~~~~~~~ Haskell is a standard lazy functional programming language; the current language version is Haskell 98, agreed in December 1998 and revised December 2002. GHC is a state-of-the-art programming suite for Haskell. Included is an optimising compiler generating good code for a variety of platforms, together with an interactive system for convenient, quick development. The distribution includes space and time profiling facilities, a large collection of libraries, and support for various language extensions, including concurrency, exceptions, and foreign language interfaces (C, whatever). GHC is distributed under a BSD-style open source license. A wide variety of Haskell related resources (tutorials, libraries, specifications, documentation, compilers, interpreters, references, contact information, links to research groups) are available from the Haskell home page (see below). On-line GHC-related resources ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Relevant URLs on the World-Wide Web: GHC home page http://www.haskell.org/ghc/ GHC developers' home page http://hackage.haskell.org/trac/ghc/ Haskell home page http://www.haskell.org/ Supported Platforms ~~~~~~~~~~~~~~~~~~~ The list of platforms we support, and the people responsible for them, is here: http://hackage.haskell.org/trac/ghc/wiki/Contributors Ports to other platforms are possible with varying degrees of difficulty. The Building Guide describes how to go about porting to a new platform: http://hackage.haskell.org/trac/ghc/wiki/Building Developers ~~~~~~~~~~ We welcome new contributors. Instructions on accessing our source code repository, and getting started with hacking on GHC, are available from the GHC's developer's site run by Trac: http://hackage.haskell.org/trac/ghc/ Mailing lists ~~~~~~~~~~~~~ We run mailing lists for GHC users and bug reports; to subscribe, use the web interfaces at http://www.haskell.org/mailman/listinfo/glasgow-haskell-users http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs There are several other haskell and ghc-related mailing lists on www.haskell.org; for the full list, see http://www.haskell.org/mailman/listinfo/ Some GHC developers hang out on #haskell on IRC, too: http://www.haskell.org/haskellwiki/IRC_channel Please report bugs using our bug tracking system. Instructions on reporting bugs can be found here: http://www.haskell.org/ghc/reportabug

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CfP: Fourth Working Conference on Programming Languages (ATPS'09)
by Janis Voigtlaender 02 Apr '09

02 Apr '09

Fourth Working Conference on Programming Languages (ATPS'09) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ http://www-ps.informatik.uni-kiel.de/atps09/ Part of the 39th annual conference of the German Gesellschaft für Informatik Luebeck (Germany), 28.9.-2.10. 2009 The conference aims at bringing together researchers and developers interested in the area of programming languages. The conference addresses all paradigms of programming languages: imperative, object-oriented, functional, logic, concurrent, parallel, or graphical programming languages, as well as languages to support the implementation of distributed systems and concepts for the integration of different paradigms. The first three Working Conferences on Programming Languages took place as part of the annual computer science conferences in Germany (Aachen 1997, Paderborn 1999, Ulm 2004). Typical but not exclusive topics are: * Design of programming languages as well as domain-specific languages * Implementation and optimization techniques * Analysis and transformation of programs * Type systems * Semantics and specification techniques * Modelling languages, object orientation * Internet programming * Verification of programs and implementations * Tools and programming environments * Frameworks, architectures, generative approaches * Experiences with specific applications * Relations between languages, architectures, processors Techniques, methods, concepts, and tools to improve the safety and reliability of programs are also of interest. The conference also welcomes contributions from enterprises. Submissions: ~~~~~~~~~~~~ Submitted papers must be written in English or German and should contain unpublished works. Contributions will be judged by relevance, originality, correctness, and readability. The significance should be clearly stated and compared to existing works. Contributions should not exceed 15 pages (LNI style, see http://www.gi-ev.de/service/publikationen/lni/autorenrichtlinien/) They must be submitted in PostScript or PDF format until April 26, 2009. Detailed information about the electronic submission is available at the web page of the conference: http://www-ps.informatik.uni-kiel.de/atps09/ It is also intended to organize a session with short presentations about unfinished projects and experience reports. Such short contributions should be clearly marked and submitted like other contributions as an extended abstract of no more than five pages. The accepted papers will be published in the proceedings of the general conference that consists of printed proceedings that will appear in the GI-Edition Lecture Notes in Informatics (LNI) with one-page abstracts and a CD containing the full papers. Import Dates: ~~~~~~~~~~~~~ Submission of contributions: April 26, 2009 Notification of acceptance/rejection: May 25, 2009 Submission of camera-ready papers: July 1, 2009 Organization: ~~~~~~~~~~~~~ Walter Dosch (University of Luebeck, dosch(a)isp.uni-luebeck.de) Michael Hanus (University of Kiel, mh(a)informatik.uni-kiel.de) Program Committee: ~~~~~~~~~~~~~~~~~~ Walter Dosch (Univ. Luebeck, Co-Chair) Wolfgang Goerigk (b+m Informatik AG) Juerg Gutknecht (ETH Zuerich) Michael Hanus (Univ. Kiel, Co-Chair) Martin Hofmann (Univ. Muenchen) Petra Hofstedt (TU Berlin) Frank Huch (Univ. Kiel) Jens Knoop (TU Wien) Herbert Kuchen (Univ. Muenster) Rita Loogen (Univ. Marburg) Markus Mueller-Olm (Univ. Muenster) Helmuth Partsch (Univ. Ulm) Peter Pepper (TU Berlin) Martin Pluemicke (BA Stuttgart) Arnd Poetzsch-Heffter (Univ. Kaiserslautern) Peter Thiemann (Univ. Freiburg) Janis Voigtlaender (TU Dresden) Wolf Zimmermann (Univ. Halle) Information about the main conference: http://www.informatik2009.de

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