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ANNOUNCE: abacate and chuchu
by Marco Túlio Pimenta Gontijo 13 Aug '12

13 Aug '12

Hi. I'm pleased to announce the first release of Abacate and Chuchu. Chuchu is a port of Ruby's Cucumber to Haskell, and Abacate is a parser for the Gherkin language, used by Cucumber. According to their web site, "Cucumber lets software development teams describe how software should behave in plain text. The text is written in a business-readable domain-specific language and serves as documentation, automated tests and development-aid - all rolled into one format." For more information on Cucumber: http://cukes.info/ Example of usage for a stack calculator: calculator.feature: Feature: Division In order to avoid silly mistakes Cashiers must be able to calculate a fraction Scenario: Regular numbers Given that I have entered 3 into the calculator And that I have entered 2 into the calculator When I press divide Then the result should be 1.5 on the screen calculator.hs: import Control.Applicative import Control.Monad.IO.Class import Control.Monad.Trans.State import Test.Chuchu import Test.HUnit type CalculatorT m = StateT [Double] m enterNumber :: Monad m => Double -> CalculatorT m () enterNumber = modify . (:) getDisplay :: Monad m => CalculatorT m Double getDisplay = do ns <- get return $ head $ ns ++ [0] divide :: Monad m => CalculatorT m () divide = do (n1:n2:ns) <- get put $ (n2 / n1) : ns defs :: Chuchu (CalculatorT IO) defs = do Given ("that I have entered" *> number <* "into the calculator") enterNumber When "I press divide" $ const divide Then ("the result should be" *> number <* "on the screen") $ \n -> do d <- getDisplay liftIO $ d @?= n main :: IO () main = chuchuMain defs (`evalStateT` []) Both packages are available at Hackage at http://hackage.haskell.org/package/abacate http://hackage.haskell.org/package/chuchu I have written them after the specification from Felipe Almeida Lessa. Any comments are welcome. -- marcot http://marcot.eti.br/

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ANNOUNCE: imm
by koral 11 Aug '12

11 Aug '12

Hello Haskell community, It's been a while since I've started developing this little project. Now that it is pretty usable, I thought it might deserve a humble annoucement. imm is a gateway from the RSS/Atom world to the mail one: it downloads RSS/Atom feeds, and for each new item it writes a file in a local maildir. It allows using any mail reader (and even any mail-related piece of software) on RSS/Atom feeds as if they were mails themselves. You can read more about it here: https://github.com/k0ral/imm http://hackage.haskell.org/package/imm Nothing trenscendental about it, I hope it will prove useful. Needless to say that any feedback is welcome, especially about Haskell tips and tricks :) . Kind regards. -- koral First release annoucement: check !

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ANNOUNCE: basic-prelude
by Dan Burton 10 Aug '12

10 Aug '12

Michael Snoyman and I are pleased to announce *basic-prelude*, an enhanced core prelude, meant for building up more complete preludes on top of. http://hackage.haskell.org/package/basic-prelude-0.1.0.0 Basic Prelude provides three major things: * Most of the usual exports from Prelude that you have come to know and love * Additional exports from *base* that are commonly used, e.g. Applicative, Monad, and Arrow stuff * Access to common non-base data types: Text, Vector, ByteString, and various collections Basic Prelude will serve as the foundation for both Michael's Classy Prelude and my Modular Prelude, and we hope that it will be attractive enough to serve as the foundation for *your* Prelude replacement as well. Note that BasicPrelude is not intended for standalone use, although importing Data.List alongside it should provide an environment nearly identical to Prelude. Basic Prelude takes the approach of hooking into existing data types and typeclasses, so it doesn't fix issues such as making Functor a superclass of Monad. Since Basic, Classy, and Modular Preludes are all still currently highly experimental, feedback is much appreciated. -- Dan Burton

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Haskell Weekly News: Issue 239
by Daniel Santa Cruz 09 Aug '12

09 Aug '12

Welcome to issue 239 of the HWN, an issue covering crowd-sourced bits of information about Haskell from around the web. This issue covers the week of July 29 to August 4, 2012. Quotes of the Week * romm: i thought i knew programming. this is like discovering a new continent. * edwardk: i think the comonads are warm fuzzy, and the monads are warm sticky. its easy to get out of a comonad, its soft and you like wearing it. monads on the other hand stick to you and are icky Top Reddit Stories * Update on GHC's new code generator Domain: hackage.haskell.org, Score: 70, Comments: 39 On Reddit: [1] http://goo.gl/NkmqH Original: [2] http://goo.gl/4bUw1 * The first video in my new series of free Haskell live coding videos Domain: youtube.com, Score: 64, Comments: 61 On Reddit: [3] http://goo.gl/f1tmg Original: [4] http://goo.gl/ihwze * hbro, Haskell based browser, ideologically similar to uzbl Domain: github.com, Score: 48, Comments: 18 On Reddit: [5] http://goo.gl/apILX Original: [6] http://goo.gl/STSwc * Thinking Functionally with Haskell | PragProg Domain: pragprog.com, Score: 32, Comments: 6 On Reddit: [7] http://goo.gl/yL4Qj Original: [8] http://goo.gl/mHss0 * Two ways of representing perfect binary trees : Inside 374 Domain: blog.ezyang.com, Score: 30, Comments: 1 On Reddit: [9] http://goo.gl/1GfdH Original: [10] http://goo.gl/JJAl1 * Hoogle: from the command line Domain: self.haskell, Score: 28, Comments: 8 On Reddit: [11] http://goo.gl/Ob9Mw Original: [12] http://goo.gl/Ob9Mw * Free monad transformers Domain: haskellforall.com, Score: 27, Comments: 11 On Reddit: [13] http://goo.gl/XbQAj Original: [14] http://goo.gl/bJfrK * If someone asked you "why Haskell?", what would you say? Domain: self.haskell, Score: 26, Comments: 73 On Reddit: [15] http://goo.gl/LQUUh Original: [16] http://goo.gl/LQUUh * Feedback from someone who learnt Haskell as his first language Domain: blog.raynes.me, Score: 25, Comments: 50 On Reddit: [17] http://goo.gl/QsnfZ Original: [18] http://goo.gl/wFOLN * Why isn't `length` part of `Foldable`? Domain: self.haskell, Score: 23, Comments: 19 On Reddit: [19] http://goo.gl/L0WWX Original: [20] http://goo.gl/L0WWX Top StackOverflow Questions * Monoidal parsing — what is it? votes: 19, answers: 2 Read on SO: [21] http://goo.gl/bVGBo * Applying multiple functions to the same value point-free style in Haskell votes: 7, answers: 4 Read on SO: [22] http://goo.gl/PifBz * How do I get consistent criterion benchmarks, or interpret results across runs? votes: 7, answers: 1 Read on SO: [23] http://goo.gl/qwT5c * Why is this prime test so slow? votes: 7, answers: 4 Read on SO: [24] http://goo.gl/QehSC * Is there a theory that combines category theory/abstract algebra and computational complexity? votes: 7, answers: 1 Read on SO: [25] http://goo.gl/CeAFw * Haskell Polymorphic Tree Sum votes: 7, answers: 1 Read on SO: [26] http://goo.gl/NqYQW * reasonably efficient pure-functional matrix product in Haskell? votes: 7, answers: 3 Read on SO: [27] http://goo.gl/8H6o9 * Is access to internal strucutre of a monad required for monad transformer? votes: 7, answers: 1 Read on SO: [28] http://goo.gl/Yln18 * Haskell sub-typeclass requires UndecidableInstances? votes: 6, answers: 2 Read on SO: [29] http://goo.gl/u9FQh * Haskell Data.List.Class and syntax votes: 6, answers: 1 Read on SO: [30] http://goo.gl/wvKEk Until next time, Daniel Santa Cruz References 1. http://hackage.haskell.org/trac/ghc/blog/newcg-update 2. http://www.reddit.com/r/haskell/comments/xmfes/update_on_ghcs_new_code_gene… 3. http://www.youtube.com/watch?v=ScS8Q32lMxA 4. http://www.reddit.com/r/haskell/comments/xfcmk/the_first_video_in_my_new_se… 5. https://github.com/k0ral/hbro 6. http://www.reddit.com/r/haskell/comments/xe0w3/hbro_haskell_based_browser_i… 7. http://pragprog.com/magazines/2012-08/thinking-functionally-with-haskell 8. http://www.reddit.com/r/haskell/comments/xmip7/thinking_functionally_with_h… 9. http://blog.ezyang.com/2012/08/statically-checked-perfect-binary-trees/ 10. http://www.reddit.com/r/haskell/comments/xov6n/two_ways_of_representing_per… 11. http://www.reddit.com/r/haskell/comments/xijsb/hoogle_from_the_command_line/ 12. http://www.reddit.com/r/haskell/comments/xijsb/hoogle_from_the_command_line/ 13. http://www.haskellforall.com/2012/07/free-monad-transformers.html 14. http://www.reddit.com/r/haskell/comments/xg75g/free_monad_transformers/ 15. http://www.reddit.com/r/haskell/comments/xlb1g/if_someone_asked_you_why_has… 16. http://www.reddit.com/r/haskell/comments/xlb1g/if_someone_asked_you_why_has… 17. http://blog.raynes.me/blog/2011/11/27/the-clojure-community-and-me/ 18. http://www.reddit.com/r/haskell/comments/xk7fz/feedback_from_someone_who_le… 19. http://www.reddit.com/r/haskell/comments/xo05l/why_isnt_length_part_of_fold… 20. http://www.reddit.com/r/haskell/comments/xo05l/why_isnt_length_part_of_fold… 21. http://stackoverflow.com/questions/11808539/monoidal-parsing-what-is-it 22. http://stackoverflow.com/questions/11709350/applying-multiple-functions-to-… 23. http://stackoverflow.com/questions/11712234/how-do-i-get-consistent-criteri… 24. http://stackoverflow.com/questions/11718067/why-is-this-prime-test-so-slow 25. http://stackoverflow.com/questions/11725899/is-there-a-theory-that-combines… 26. http://stackoverflow.com/questions/11742405/haskell-polymorphic-tree-sum 27. http://stackoverflow.com/questions/11768656/reasonably-efficient-pure-funct… 28. http://stackoverflow.com/questions/11792275/is-access-to-internal-strucutre… 29. http://stackoverflow.com/questions/11707171/haskell-sub-typeclass-requires-… 30. http://stackoverflow.com/questions/11770733/haskell-data-list-class-and-syn…

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Departmental Lectureship vacancy in Software Engineering Programme, University of Oxford
by Jeremy.Gibbons＠cs.ox.ac.uk 07 Aug '12

07 Aug '12

[I sent this announcement a few hours ago, but I'm afraid that the URL for the further details was incorrect. Corrected version attached. My apologies for the annoyance. -jg] We have a vacancy in the Software Engineering Programme for a Departmental Lecturer, for a fixed term of four years from 1st December or as soon as possible thereafter. The SEP offers part-time professional education to practitioners in industry; there are two MSc degrees, one in Software Engineering and one in Software and Systems Security. The main responsibility is to teach or assist on courses in core subject areas such as object-oriented programming and design, software testing, model-driven engineering, and data representation and retrieval. The post is intended as a career development position for a junior academic; applicants should have or be just about to complete a doctoral degree in computer science or software engineering, and the contract will not be renewable after the four years. You can read more about the SEP at http://www.softeng.ox.ac.uk/ The full details of the position are here: https://www.recruit.ox.ac.uk/pls/hrisliverecruit/erq_jobspec_version_4.jobs… The application closing date is 21st September. Please feel free to write to me if you have any queries. Jeremy Gibbons Professor of Computing Director of Software Engineering Programme www.cs.ox.ac.uk/jeremy.gibbons jeremy.gibbons(a)cs.ox.ac.uk

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Departmental Lectureship vacancy in Software Engineering Programme, University of Oxford
by Jeremy.Gibbons＠cs.ox.ac.uk 07 Aug '12

07 Aug '12

We have a vacancy in the Software Engineering Programme for a Departmental Lecturer, for a fixed term of four years from 1st December or as soon as possible thereafter. The SEP offers part-time professional education to practitioners in industry; there are two MSc degrees, one in Software Engineering and one in Software and Systems Security. The main responsibility is to teach or assist on courses in core subject areas such as object-oriented programming and design, software testing, model-driven engineering, and data representation and retrieval. The post is intended as a career development position for a junior academic; applicants should have or be just about to complete a doctoral degree in computer science or software engineering, and the contract will not be renewable after the four years. You can read more about the SEP at http://www.softeng.ox.ac.uk/ The full details of the position are here: https://www.recruit.ox.ac.uk/pls/hrisliverecruit/erq_jobspec_version_4.disp… The application closing date is 21st September. Please feel free to write to me if you have any queries. Jeremy Gibbons Professor of Computing Director of Software Engineering Programme www.cs.ox.ac.uk/jeremy.gibbons jeremy.gibbons(a)cs.ox.ac.uk

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Call for Participation: Implementation and Application of Functional Languages 2012
by José Pedro Magalhães 07 Aug '12

07 Aug '12

Apologies for multiple postings. -------------------------------------------------------------------------------- CALL FOR PARTICIPATION 24th Symposium on Implementation and Application of Functional Languages (IFL 2012) University of Oxford, UK, August 30-September 1, 2012 http://www.cs.ox.ac.uk/conferences/IFL2012/ This year IFL will be hosted by the University of Oxford, within the idyllic setting of the dreaming spires and picturesque colleges, which have been the home to academic endeavour and research for over nine centuries. The symposium will be held between 30 August and 1 September, 2012. Early registration closes on 10 August. Late registration closes on 23 August, but conference accommodation can only be booked until 13 August. The registration fee includes lunches and refreshments, BBQ on the first evening, an afternoon excursion, and the conference banquet. To register, please follow the link: http://www.cs.ox.ac.uk/conferences/IFL2012/registration.html Invited Speaker --------------- Fritz Henglein, from the Department of Computer Science at the University of Copenhagen, is the invited speaker of IFL 2012. He will be talking about "generic sorting and partitioning in linear time and fully abstractly—simultaneously". Schedule -------- There will be 38 talks presented at IFL 2012. The schedule of presentations is now online at: http://www.cs.ox.ac.uk/conferences/IFL2012/schedule.html Scope ----- The goal of the IFL symposia is to bring together researchers actively engaged in the implementation and application of functional and function-based programming languages. IFL 2012 will be a venue for researchers to present and discuss new ideas and concepts, work in progress, and publication-ripe results related to the implementation and application of functional languages and function-based programming. Following the IFL tradition, IFL 2012 will use a post-symposium review process to produce formal proceedings which will be published by Springer Verlag in the Lecture Notes in Computer Science series. All participants in IFL 2012 are invited to submit either a draft paper or an extended abstract describing work to be presented at the symposium. Organising committee -------------------- Ralf Hinze (Chair), University of Oxford, UK Nicolas Wu, University of Oxford, UK José Pedro Magalhães, University of Oxford, UK

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ANNOUNCE: tardis
by Dan Burton 07 Aug '12

07 Aug '12

I'm pleased to announce that I've uploaded the *tardis* package to hackage. http://hackage.haskell.org/package/tardis-0.2.0.0 *TardisT* is a monad transformer that combines the (regular, "forwards") State monad with the "backwards State monad", allowing you to communicate on two channels of state: one is "backwards travelling" state, while the other is "forwards travelling" state. Its primitives are comparable to the State monad's "get" and "put", but the names disambiguate which channel they operate on: getPast :: Monad m => TardisT bw fw m fw getFuture :: Monad m => TardisT bw fw m bw sendPast :: Monad m => bw -> TardisT bw fw m () sendFuture :: Monad m => fw -> TardisT bw fw m () These primitives allow you to write some very amusing timey-wimey code, but it only works in the presence of sufficient laziness. If you run into an infinite loop, try adding laziness annotations everywhere, and make sure that what you are trying to do is not a time paradox. I've provided both *transformers* and *mtl* style modules: Control.Monad.Trans.Tardis contains the transformer, while Control.Monad.Tardis.Class contains the MonadTardis class, and Control.Monad.Tardis re-exports both as well as the TardisT instance for MonadTardis. See the readme on github for more details: https://github.com/DanBurton/tardis#readme As a side note, since the code base is relatively small, it can also serve as a simple demonstration of how to use a cabal flag in conjunction with CPP to selectively include swaths of code (see Control/Monad/Tardis.hs and tardis.cabal). I'm not entirely sold on the naming conventions for the package (including the package name), and am open to suggestions. -- Dan Burton

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Call for Participation: HOPE 2012
by Amal Ahmed 06 Aug '12

06 Aug '12

********************************************************************* CALL FOR PARTICIPATION HOPE 2012 The 1st ACM SIGPLAN Workshop on Higher-Order Programming with Effects Sunday, September 9, 2012 Copenhagen, Denmark To be held in conjunction with ICFP 2012 http://hope2012.mpi-sws.org ********************************************************************* IMPORTANT DATES Early registration deadline: August 9, 2012 *** only days away! *** Hotel reservation deadline: August 9, 2012 (for most hotels) VENUE HOPE 2012 and all ICFP'12 affiliated events will take place at DGI-byen's conference center - CPH Conference, Tietgensgade 65, DK 1704 Copenhagen V. More information at: http://icfpconference.org/icfp2012/local.html HOPE 2012 HOPE is a *new workshop* that is intended to bring together researchers interested in the design, semantics, implementation, and verification of higher-order effectful programs. This 1st edition of HOPE is dedicated to John Reynolds, whose work is an inspiration to us all. There were 21 talk submissions, of extraordinarily high quality. As the workshop is only one day long, we were only able to accept 13 of them for presentation at the workshop. So there will be 13 contributed talks, but no invited talks or other sessions. We expect this to be a very high-octane workshop! PROGRAM The program is included at the end of this email; it can also be found here: http://hope2012.mpi-sws.org/ PROGRAM CHAIRS Amal Ahmed (Northeastern University) Derek Dreyer (MPI-SWS, Germany) PROGRAM COMMITTEE Jim Laird (University of Bath) Rasmus Møgelberg (IT University of Copenhagen) Greg Morrisett (Harvard University) Aleks Nanevski (IMDEA Software Institute) David Naumann (Stevens Institute of Technology) Matthew Parkinson (Microsoft Research Cambridge) François Pottier (INRIA Rocquencourt) Amr Sabry (Indiana University) Eijiro Sumii (Tohoku University) Nikhil Swamy (Microsoft Research Redmond) Nobuko Yoshida (Imperial College London) PRELIMINARY PROGRAM SUNDAY, September 9, 2012 Session 1: Verification 9:00 Modular Specification and Verification of Delegation with SMT Solvers Ioannis Kassios, Peter Müller 9:30 On Higher-Order Separation Logic for Higher-Order Concurrent Imperative Programs Kasper Svendsen, Lars Birkedal, Matthew Parkinson 10:00 Verifying an Open Compiler from ML to Assembly James T. Perconti, Amal Ahmed 10:30 BREAK Session 2: Monads and More 11:00 Handlers in Action Ohad Kammar, Sam Lindley, Nicolas Oury 11:30 Contract Monitoring as an Effect Zachary Owens 12:00 HOPE for a Type-Theoretic Understanding of Zero-Knowledge Noam Zeilberger 12:30 LUNCH Session 3: Types and Effects 2:00 Koka: A Language with Row-Polymorphic Effect Inference Daan Leijen 2:30 Effects for Funargs Jeremy Siek, Michael Vitousek, Jonathan Turner 3:00 Generative Names and Dependent Types Andrew Pitts 3:30 BREAK Session 4: Logical Relations and Parametricity 4:00 Logical Relations for Fine-Grained Concurrency Aaron Turon, Jacob Thamsborg, Amal Ahmed, Lars Birkedal, Derek Dreyer 4:30 Logical Relations for a Manifest Calculus, Fixed Taro Sekiyama, Atsushi Igarashi 5:00 Proof-Relevant Logical Relations Nick Benton, Martin Hofmann, Andrew Kennedy, Vivek Nigam 5:30 Two Theories of Information Hiding Uday Reddy

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Call for Participation: XLDI 2012 (@ ICFP 2012)
by Torsten Grust 03 Aug '12

03 Aug '12

CALL FOR PARTICIPATION XLDI 2012 First International Workshop on Cross-Model Language Design and Implementation http://workshops.inf.ed.ac.uk/xldi2012/ Affiliated with ICFP 2012, Copenhagen, Denmark Sponsored by ACM SIGPLAN September 9, 2012 (Sunday before ICFP) You need an ICFP Sunday pass to participate in XLDI 2012. For details on ICFP registration please see http://icfpconference.org/icfp2012/registration.html XLDI 2012 focuses on the foundations, design, implementation, and applications of languages that smoothly integrate different execution or data models. We have assembled an interesting program of 7 presentations, covering software-defined networks, Haskell DSLs for interactive web services, typing of massive JSON datasets, rewrite optimization of dataflow programs, and languages designed to build domain-specific runtimes. INVITED SPEAKERS: - Fritz Henglein (DIKU, University of Copenhagen) - Christopher Re (University of Wisconsin) SCIENTIFIC PROGRAMME: - Naga Praveen Katta, Jennifer Rexford, David Walker: Logic Programming for Software Defined Networks - Andrew Farmer, Andy Gill: Haskell DSLs for Interactive Web Services - Dario Colazzo, Giorgio Ghelli, Carlo Sartiani: Typing Massive JSON Datasets - Fabian Hueske, Aljoscha Krettek, Kostas Tzoumas: Enabling Rewrite Optimizations of Data Flow Programs Through Static Code Analysis - Panchapakesan Shyamshankar, Zachary Palmer, Yanif Ahmad: K3: Language Design for Building Multi-Platform, Domain-Specific Runtimes SPONSORS: XLDI 2012 is sponsored by LogicBlox and Oracle Labs. We are looking forward to see you in Copenhagen, --James Cheney, Torsten Grust (XLDI co-chairs)

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