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CFP: 2012 ML workshop
by oleg＠okmij.org 16 Mar '12

16 Mar '12

ACM SIGPLAN Workshop on ML Thursday, September 13th, 2012, Copenhagen, Denmark (co-located with ICFP) http://www.lexifi.com/ml2012 ======================================================================= The ML family of programming languages includes dialects known as Standard ML, OCaml, and F#. These languages have inspired a large amount of computer-science research, both practical and theoretical. This workshop aims to provide a forum where users, developers and researchers of ML languages and related technology can interact and discuss ongoing research, open problems and innovative applications. The format of ML 2012 will continue the return in 2010 and 2011 to a more informal model: a workshop with presentations selected from submitted abstracts. The workshop will not publish proceedings, so any contributions may be submitted for publication elsewhere. We hope that this format will encourage the presentation of exciting (if unpolished) research and deliver a lively workshop atmosphere. SCOPE ----- We seek research presentations on topics related to ML, including but not limited to * applications: case studies, experience reports, pearls, etc. * extensions: higher forms of polymorphism, generic programming, objects, concurrency, distribution and mobility, semi-structured data handling, etc. * type systems: inference, effects, overloading, modules, contracts, specifications and assertions, dynamic typing, error reporting, etc. * implementation: compilers, interpreters, type checkers, partial evaluators, runtime systems, garbage collectors, etc. * environments: libraries, tools, editors, debuggers, cross-language interoperability, functional data structures, etc. * semantics: operational, denotational, program equivalence, parametricity, mechanization, etc. Three kinds of submissions will be accepted: Research Presentations, Experience Reports and Demos. * Research Presentations: Research presentations should describe new ideas, experimental results, significant advances in ML-related projects, or informed positions regarding proposals for next-generation ML-style languages. We especially encourage presentations that describe work in progress, that outline a future research agenda, or that encourage lively discussion. These presentations should be structured in a way which can be, at least in part, of interest to (advanced) users. * Experience Reports: Users are invited to submit Experience Reports about their use of ML languages. These presentations do not need to contain original research but they should tell an interesting story to researchers or other advanced users, such as an innovative or unexpected use of advanced features or a description of the challenges they are facing or attempting to solve. * Demos: Live demonstrations or short tutorials should show new developments, interesting prototypes, or work in progress, in the form of tools, libraries, or applications built on or related to ML. (Please note that you will need to provide all the hardware and software required for your demo; the workshop organizers are only able to provide a projector.) Each presentation should take 20-25 minutes, except demos, which should take 10-15 minutes. The exact time will be decided based on the number of accepted submissions. SUBMISSION INSTRUCTIONS ----------------------- Submissions should be at most two pages, in PDF format, and printable on US Letter or A4 sized paper. Submissions longer than a half a page should include a one-paragraph synopsis suitable for inclusion in the workshop program. Submissions must be uploaded to the following website before the submission deadline (2012-06-04): https://www.easychair.org/conferences/?conf=ml2012 For any question concerning the scope of the workshop or the submission process, please contact the program chair (alain(a)frisch.fr) IMPORTANT DATES --------------- * 2012-06-04: Submission * 2012-07-13: Notification * 2012-09-13: Workshop PROGRAM COMMITTEE ----------------- Alain Frisch (chair) (LexiFi) Anders Schack-Nielsen (SimCorp) Cedric Fournet (Microsoft Research) Francois Pottier (INRIA) Gian Ntzik (Imperial College) Jeremy Yallop Keiko Nakata (Institute of Cybernetics, Tallinn) Matthias Blume (Google) Oleg Kiselyov Stephen Weeks (Jane Street Capital) Tomas Petricek (University of Cambridge) STEERING COMMITTEE ------------------ Andreas Rossberg (Google) Chung-chieh Shan (Cornell University) Eijiro Sumii (chair) (Tohoku University) Jacques Garrigue (Nagoya University) Matthew Fluet (Rochester Institute of Technology) Robert Harper (Carnegie Mellon University) Yaron Minsky (Jane Street)

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Haskell Weekly News: Issue 218
by Daniel Santa Cruz 16 Mar '12

16 Mar '12

Welcome to issue 218 of the HWN, an issue covering crowd-sourced bits of information about Haskell from around the web. This issue cover the weeks of February 26 to March 10, 2012. You can find the HTML version at: http://contemplatecode.blogspot.com/2012/03/haskell-weekly-news-issue-218.h… Quotes of the Week * monochrom: shapr is not "normal". he got a decent job, then went to school. * quicksilver: typeclasses are absolutely not sugar for a record of functions quicksilver: they're unsugar. quicksilver: they're a benighted bitter poison. * edwardk: i'm not willing to give up orders of magnitude worth of performance to get a bad hack edwardk: if you want that, go code in scheme * (on pointless black magic) mgsloan: welcome to excessively pointless plumbing operators :) byorgey: mgsloan: that's... terrifying DanBurton: you should put it on hackage * cheater_: maybe you should try /part since we're talking about perfect-world situations * edwardk: i used to be a huge proponent of unicode syntax everywhere, then i used agda ;) * cmccann: free advice is, of course, any advice which satisfies the properties expected given the definition of "advice", but nothing further ;] * shachaf: "magic" is just another word for "primitive" * dylukes: I'm getting way more acquainted with the GHC build system than I'd like to be. * JoeyA: Inform7 is a programming language. A programming language tells a computer what to do. The computer is in a room. You are facing West. * mauke: sorry, the current time is not a constant lukish: It's a pity * dfletcher: > ((++" Batman!") . take 48 . cycle . show) (0/0) Top Reddit Stories * New unordered-containers release improves performance by as much as 2x, using HAMTs Domain: blog.johantibell.com, Score: 64, Comments: 46 On Reddit: [1] http://goo.gl/D6yTb Original: [2] http://goo.gl/5YUph * A humble suggestion for visual pure functional programming Domain: i.imgur.com, Score: 59, Comments: 59 On Reddit: [3] http://goo.gl/eUMrk Original: [4] http://goo.gl/DSFnj * Spike: experimental web browser in Haskell Domain: self.haskell, Score: 53, Comments: 22 On Reddit: [5] http://goo.gl/ZTR1j Original: [6] http://goo.gl/ZTR1j * GHC 7.4.1 speeds up arbtt by a factor of 22 Domain: joachim-breitner.de, Score: 51, Comments: 18 On Reddit: [7] http://goo.gl/XVBDt Original: [8] http://goo.gl/IL6EL * Eff 3.0 is out, a functional language with first-class computational effects and handlers (an alternative to monads) Domain: math.andrej.com, Score: 49, Comments: 12 On Reddit: [9] http://goo.gl/1Idw0 Original: [10] http://goo.gl/iwHlG * What's the most clever piece of Haskell code you know? Domain: self.haskell, Score: 47, Comments: 64 On Reddit: [11] http://goo.gl/T1u9t Original: [12] http://goo.gl/T1u9t * Diagrams 0.5 released: powerful, flexible embedded domain-specific language for creating vector graphics Domain: byorgey.wordpress.com, Score: 40, Comments: 7 On Reddit: [13] http://goo.gl/e75Yx Original: [14] http://goo.gl/565c1 * Faster Javascript Through Category Theory Domain: johnbender.us, Score: 39, Comments: 5 On Reddit: [15] http://goo.gl/UgvTr Original: [16] http://goo.gl/TLK4k * I'm writing a Haskell book. Almost finished the 3rd chapter. Would like feedback. Domain: bit.ly, Score: 36, Comments: 48 On Reddit: [17] http://goo.gl/AzwhR Original: [18] http://goo.gl/AzwhR * Level 0 -- a Snake clone using SDL, with a nice interactive map editor Domain: quasimal.com, Score: 28, Comments: 5 On Reddit: [19] http://goo.gl/x9gZk Original: [20] http://goo.gl/meSPo * Parallel Haskell Digest 8: MVar, summer school, Simon PJ @ YOW, and more Domain: well-typed.com, Score: 27, Comments: 1 On Reddit: [21] http://goo.gl/MDzrI Original: [22] http://goo.gl/OC6O6 * Avoid cabal hell: find nirvana Domain: yesodweb.com, Score: 27, Comments: 30 On Reddit: [23] http://goo.gl/ryd5e Original: [24] http://goo.gl/Yyzqd * Improvements to HashMap and HashSet creation Domain: blog.johantibell.com, Score: 26, Comments: 1 On Reddit: [25] http://goo.gl/yh2zs Original: [26] http://goo.gl/u9uhg * The Day Python Embarassed Imperative Programming » What, then, Shall We Say? Domain: the-27th-comrade.appspot.com, Score: 25, Comments: 20 On Reddit: [27] http://goo.gl/5KIOx Original: [28] http://goo.gl/Wi47v * Improbable uses of unsafeCoerce Domain: gist.github.com, Score: 25, Comments: 25 On Reddit: [29] http://goo.gl/cN0LE Original: [30] http://goo.gl/cxfSc Top StackOverflow Questions * Haskell: Lists, Arrays, Vectors, Sequences votes: 32, answers: 1 Read on SO: [31] http://goo.gl/YHVpC * Why type classes in Haskell were difficult to implement? votes: 20, answers: 1 Read on SO: [32] http://goo.gl/LoLHe * runST and function composition votes: 18, answers: 3 Read on SO: [33] http://goo.gl/6NSvR * How do you compute the difference between successive elements of a list of unknown size, functionally? votes: 16, answers: 7 Read on SO: [34] http://goo.gl/rnc8l * Do we care about the 'past' in FRP? votes: 16, answers: 1 Read on SO: [35] http://goo.gl/oR2rd * “evaluate” function votes: 16, answers: 1 Read on SO: [36] http://goo.gl/ShLMT * What's preferred among liftM, lilftA, etc votes: 15, answers: 1 Read on SO: [37] http://goo.gl/y8apA * Name of type pattern: R a b = Q (a -> (R a b,b)) votes: 14, answers: 3 Read on SO: [38] http://goo.gl/kRMgn * Haskell offline documentation? votes: 12, answers: 2 Read on SO: [39] http://goo.gl/Hih3z * Program design in Haskell: how to do simulation without mutability votes: 12, answers: 3 Read on SO: [40] http://goo.gl/ODJjT Until next time, Daniel Santa Cruz References 1. http://blog.johantibell.com/2012/03/announcing-unordered-containers-02.html 2. http://www.reddit.com/r/haskell/comments/ql9m5/new_unorderedcontainers_rele… 3. http://i.imgur.com/TOZZZ.png 4. http://www.reddit.com/r/haskell/comments/q7m8i/a_humble_suggestion_for_visu… 5. http://www.reddit.com/r/haskell/comments/qhce6/spike_experimental_web_brows… 6. http://www.reddit.com/r/haskell/comments/qhce6/spike_experimental_web_brows… 7. http://www.joachim-breitner.de/blog/archives/546-GHC-7.4.1-speeds-up-arbtt-… 8. http://www.reddit.com/r/haskell/comments/q86iw/ghc_741_speeds_up_arbtt_by_a… 9. http://math.andrej.com/eff/ 10. http://www.reddit.com/r/haskell/comments/qosr7/eff_30_is_out_a_functional_l… 11. http://www.reddit.com/r/haskell/comments/qn7nk/whats_the_most_clever_piece_… 12. http://www.reddit.com/r/haskell/comments/qn7nk/whats_the_most_clever_piece_… 13. http://byorgey.wordpress.com/2012/03/09/announcing-diagrams-0-5/ 14. http://www.reddit.com/r/haskell/comments/qpkxb/diagrams_05_released_powerfu… 15. http://johnbender.us/2012/02/29/faster-javascript-through-category-theory/ 16. http://www.reddit.com/r/haskell/comments/qbuk8/faster_javascript_through_ca… 17. http://bit.ly/xDsDSj 18. http://www.reddit.com/r/haskell/comments/qquc5/im_writing_a_haskell_book_al… 19. http://quasimal.com/projects/level_0.html 20. http://www.reddit.com/r/haskell/comments/qcrhj/level_0_a_snake_clone_using_… 21. http://www.well-typed.com/blog/64 22. http://www.reddit.com/r/haskell/comments/qefzt/parallel_haskell_digest_8_mv… 23. http://www.yesodweb.com/blog/2012/03/cabal-nirvana 24. http://www.reddit.com/r/haskell/comments/qkqdj/avoid_cabal_hell_find_nirvan… 25. http://blog.johantibell.com/2012/03/improvements-to-hashmap-and-hashset.html 26. http://www.reddit.com/r/haskell/comments/qp7w1/improvements_to_hashmap_and_… 27. http://the-27th-comrade.appspot.com/blog/ahJzfnRoZS0yN3RoLWNvbXJhZGVyDAsSBU… 28. http://www.reddit.com/r/haskell/comments/q7ykt/the_day_python_embarassed_im… 29. https://gist.github.com/1934179 30. http://www.reddit.com/r/haskell/comments/qadwm/improbable_uses_of_unsafecoe… 31. http://stackoverflow.com/questions/9611904/haskell-lists-arrays-vectors-seq… 32. http://stackoverflow.com/questions/9602176/why-type-classes-in-haskell-were… 33. http://stackoverflow.com/questions/9468963/runst-and-function-composition 34. http://stackoverflow.com/questions/9512513/how-do-you-compute-the-differenc… 35. http://stackoverflow.com/questions/9526836/do-we-care-about-the-past-in-frp 36. http://stackoverflow.com/questions/9553943/evaluate-function 37. http://stackoverflow.com/questions/9509350/whats-preferred-among-liftm-lilf… 38. http://stackoverflow.com/questions/9487760/name-of-type-pattern-r-a-b-q-a-r… 39. http://stackoverflow.com/questions/9454793/haskell-offline-documentation 40. http://stackoverflow.com/questions/9548913/program-design-in-haskell-how-to…

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[ANNOUNCE] JuicyPixels 1.1 - image loading library (maintenance release)
by Vincent Berthoux 14 Mar '12

14 Mar '12

Hello list, This is a maintenance release without new functionality, the central change is the switch from Haskell Array to Data.Vector (to ease it's use for OpenGL texture loading). Juicy.Pixels 1.1 change log : - Fixing automatic bitmap decoding, the decodeImage function wasn't trying to decode bitmap - Converting Haskell array types to Data.Vector (thanks to Jason Dagit) - Some tiny documentation enhancement Hackage : http://hackage.haskell.org/package/JuicyPixels GitHub : https://github.com/Twinside/Juicy.Pixels Thanks Vincent Berthoux

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ANNOUNCE: join (UHac <$> DHD)
by Sean Leather 13 Mar '12

13 Mar '12

You can still join us at the DHD >>= UHac, but the time is running out. http://www.haskell.org/haskellwiki/DHD_UHac Deadline: April 1 (no fooling!) We've also have a few updates: * We put the DHD program up, at least as much of it as we have. http://www.haskell.org/haskellwiki/DHD_UHac/DHD_Program * As you can see from the program, there is still room for more speakers. In particular, we'd like to hear from people coming outside Utrecht and the Netherlands. We'd also like to see more lightning talks. Send Sean an email with your idea: leather(a)cs.uu.nl * UHac on Friday has moved to a "new" location. Actually, it's the same location as on Saturday and Sunday, so that should make things easier. See you in Utrecht! The Organizers: Sean Leather Jurriën Stutterheim Jurriaan Hage P.S. Make sure your Monad is also a Functor. P.P.S. Apologies for multiple copies.

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PhD and postdoc positions in regular expressions and types
by Fritz Henglein 13 Mar '12

13 Mar '12

Two PhD and postdoc positions are available at DIKU, the Department of Computer Science at the University of Copenhagen, in the Project *Kleene Meets Church (KMC): Regular Expressions and Types*. The overall objective of KMC is to investigate the type-theoretical foundations for the prevalent use of regular expressions (and related grammars) for extracting information from an input, not just classifying it into accepting/nonaccepting; to explore and demonstrate guaranteed safety and expressiveness of programming with regular expressions as types; and to drastically improve semantic predictability and computational scalability vis a vis commonly used regular expression processing tools such as Perl. Application deadline: *March 31st, 2012*. For information on the positions and application requirements, please see http://diku.dk/english/about/vacancies

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PhD position at Radboud University, The Netherlands - NECTOP project
by Peter Achten 12 Mar '12

12 Mar '12

Dear all, Please find attached information about a PhD position at the Model Based Software Development department of the Computer and Information Sciences Institute at the Radboud University, The Netherlands. With kind regards, on behalf of Rinus Plasmeijer, Peter Achten

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ANNOUNCE: freesect-0.0.5
by Ras Far 11 Mar '12

11 Mar '12

Hi, I'm pleased to announce my first package, freesect, which is a Haskell syntax extension to generalise sections. Please visit the homepage http://www.fremissant.net/freesect for more information. The package is also available on Hackage. Some previous discussion occurred on the haskell-cafe thread http://www.mail-archive.com/haskell-cafe@haskell.org/msg97643.html It's been an exhilarating experience! Kind Regards, Andrew Seniuk (rasfar on #haskell)

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ANNOUNCE: diagrams 0.5
by Brent Yorgey 09 Mar '12

09 Mar '12

I am pleased to announce the release of version 0.5 of diagrams [1], a full-featured framework and embedded domain-specific language for declarative drawing. Check out the gallery [2] for examples of what it can do! [1] http://projects.haskell.org/diagrams [2] http://projects.haskell.org/diagrams/gallery.html Highlights of this release include: - A new diagrams-contrib [3] package of user-contributed modules, which so far contains code for tree drawing, Apollonian gaskets, planar tilings, "wrapped" layout, and turtle graphics. - Experimental support for animation, built on top of the new active [4] library. - Numerous small additions and improvements, including more general rounded rectangle shapes and better text support. - Much better performance in some common situations, such as laying out a very long list of diagrams using 'cat' and related combinators. - Added support for GHC 7.4. See the release notes [5] for complete details, and the diagrams wiki [6] for help migrating code from 0.4 to 0.5 (changes should be minimal). [3] http://hackage.haskell.org/package/diagrams%2Dcontrib [4] http://hackage.haskell.org/package/active [5] http://projects.haskell.org/diagrams/releases.html [6] http://www.haskell.org/haskellwiki/Diagrams/Migrate0.5 Try it out ---------- For the truly impatient: cabal install gtk2hs-buildtools cabal install diagrams Diagrams is supported under GHC 6.12, 7.0, 7.2, and 7.4. However, getting cairo to build can be tricky on some platforms; see the diagrams wiki [8] for more information and workarounds regarding specific platforms. (A new native SVG backend is in the works, targeted for the 0.6 release.) To get started with diagrams, read the quick tutorial [9], which will introduce you to the fundamentals of the framework. For those who are even less impatient but want to really dig in and use the power features, read the user manual [10]. [7] http://projects.haskell.org/gtk2hs/development/#development [8] http://www.haskell.org/haskellwiki/Diagrams [9] http://projects.haskell.org/diagrams/tutorial/DiagramsTutorial.html [10] http://projects.haskell.org/diagrams/manual/diagrams-manual.html Get involved ------------ Subscribe to the project mailing list [11], and/or come hang out in the #diagrams IRC channel on freenode.org for help and discussion. Make some diagrams. Fix some bugs [12]. Submit your cool examples for inclusion in the gallery or your cool code for inclusion in the diagrams-contrib package! [11] http://groups.google.com/group/diagrams-discuss [12] http://code.google.com/p/diagrams/issues/list Happy diagramming! Brought to you by the diagrams team: - Peter Hall - Ian Ross - Michael Sloan - Ryan Yates - Brent Yorgey with contributions from: - Sam Griffin - Claude Heiland-Allen - John Lato - Vilhelm Sjoberg - Luite Stegeman - Kanchalai Suveepattananont - Scott Walck

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[ANN] gtk2hs-0.12.3
by wagnerdm＠seas.upenn.edu 09 Mar '12

09 Mar '12

Hello all! I'm pleased to announce the release of gtk2hs, the definitive Haskell bindings to Gtk+. This release includes GHC-7.4 support, as well as the new widgetRestore{Fg,Bg,Text,Base} bindings. Get it from the Hackage nearest you! cabal update cabal install gtk2hs-buildtools cabal install gio gtk All the best. - the gtk2hs team

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Re: [Haskell] Displaying trees in Haskell
by John Lato 08 Mar '12

08 Mar '12

> From: Luana Fagarasan <luana_0105(a)yahoo.com> > > Hello, > > I am quite new to Haskell and I am seeking the best way to > display trees graphically when using Haskell. I have looked on > the web, but am still not clear! IMHO Haskell is a good language for this sort of task; there are several graphics libraries that I would consider fairly mature and reliable. I have a project that uses "diagrams" (http://hackage.haskell.org/package/diagrams) to draw a tree; the code is: > import Diagrams.Prelude > > drawTree (Node dt children) = > fmap (queryFunc $ nodePath dt) (circle 1 > # scaleY 0.5 > # fc darkblue > # lw 0.1 > # lc deepskyblue > # pad 1.1 > # named (show $ nodePath dt) > ) > === > (hcat' with {sep = 0.2} (map drawTree children) # centerX) drawTree could be understood as "draw the current node on top of the diagram produced by applying the node's children to drawTree". This function just draws each node as an oval. "#" is a diagrams-provided operator to apply parameters to a diagram. The "queryFunc" and "named" stuff is to enable queries into the diagram, so that mouse click coordinates can be converted into a label for the node (as retrieved by "nodePath"). Depending on what you want to display for each node, the image could be as simple or complex as you would like. Probably the most full-featured diagrams backend uses Cairo, so your drawings can be rendered in any format Cairo supports (including GTK widgets). Other backends are also available although I don't know as much about them. HTH, John Lato

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