November 2011 - Haskell

Job Opportunity at Parallel Scientific
by Peter Braam 21 Nov '11

21 Nov '11

Parallel Haskell Programmers Parallel Scientific, LLC is a Boulder, CO based early stage, but funded startup company working in the area of scalable parallelization for scientific and large data computing. We are implementing radically new software tools for the creation and optimization of parallel programs benefiting applications and leveraging modern systems architecture. We build on our mathematical knowledge, cutting edge programming languages and our understanding of systems software and hardware. We are currently working with the Haskell development team and major HPC laboratories world wide on libraries and compiler extensions for parallel programming. Parallel Scientific was founded by Dr Peter Braam in 2010. Peter formerly taught mathematics and computer science at Oxford and Carnegie Mellon. Then he contributed file systems to Linux and invented Lustre (which provides storage to 9 of the top 10 systems in the world). He ran several successful startups, and Parallel Scientific is run by an very experienced management team and board. Successful candidates can in some cases work remotely and will work in a modern virtual environment. We provide training in advanced processes for software design and implementation and domain specific knowledge. Required skills: - Very strong background in computer science or mathematics - Experience with Haskell - Knowledge of systems programming and operating systems functionality - Knowledge of system architectures, such as high performance networking, memory architectures, multi and manycore CPUs and GPGPUs - Experience with performance tuning of parallel or concurrent algorithms - Experience designing and implementing concurrent or parallel programs Experience in one or more of the following areas is desirable: - Experience with Haskell compiler technology - In depth knowledge of core Haskell libraries for parallel programming (NDP, REPA etc) - Experience in the area of middleware algorithms for data flow programming, graphs, cloud based data analytics, or sparse matrices - Domain specific knowledge in scientific programming areas related to irregular and sparse problems, e.g. data analytics using graph analysis, genomics, tightly connected numerical analysis - Experience with performance tuning for parallel applications on multi core systems (e.g. with the Intel toolkit), for GPGPU's using Cuda/OpenCL or with MPI/OpenMP on clusters of SMPs To apply, please send a resume to jobs(a)parsci.com.

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Haskell Weekly News: Issue 208
by Daniel Santa Cruz 17 Nov '11

17 Nov '11

Welcome to issue 208 of the HWN, a newsletter covering developments in the Haskell community. This release covers the week of November 6 to 12, 2011. You can find the HTML version at: http://contemplatecode.blogspot.com/2011/11/haskell-weekly-news-issue-208.h… New and Updated Projects * GHC (Ian Lynagh; 7.2.2) bugfix release for the 7.2 branch. [1] http://goo.gl/eB4X6 * CoreErlang (Alex Kropivny; 0.0.2) New maintainer, plus some bug fixes. [2] http://goo.gl/TMUWs * virthualenv (Bartek ƒwik≈owski) A tool inspired by Python's virtualenv. [3] http://goo.gl/3Jvc0 * transformers-base, transformers-abort, monad-abort-fd (Mikhail Vorozhtsov). [4] http://goo.gl/DRNgt Quotes of the Week * Nimatek: People shouldn't be able to add two and two in Haskell without knowing monoids! * shachaf: Sometimes things are complicated because the domain is complicated. Other times things are complicated because edwardk. * shachaf: It's-a me, MonadIO! * elliott: a typeclass is nothing without semantics * Jafet: I didn't know what your question was so I answered the question that I liked * steakknife: Skip multidimensional types and go straight types that can express general relativity. * ddarius: "use the right platitude for the job" * balor: hmm....do not try to compile a file with a 30mb string in it Top Reddit Stories * Quick poll: upvote if you think GHC should enable -O by default, downvote if you think -O0 should continue to be the default Domain: self.haskell, Score: 68, Comments: 46 On Reddit: [5] http://goo.gl/q43Ur Original: [6] http://goo.gl/q43Ur * What's going on with "id id id ... id 0"? Domain: self.haskell, Score: 46, Comments: 25 On Reddit: [7] http://goo.gl/a57l0 Original: [8] http://goo.gl/a57l0 * HaskellDB: A long tutorial Domain: chrisdone.com, Score: 45, Comments: 6 On Reddit: [9] http://goo.gl/FYBiU Original: [10] http://goo.gl/794G2 * The Agda mailing list has the best questions [somewhat off topic] Domain: lists.chalmers.se, Score: 41, Comments: 1 On Reddit: [11] http://goo.gl/ec5gB Original: [12] http://goo.gl/ODpKV * Virtual Haskell Environment Domain: paczesiowa.blogspot.com, Score: 40, Comments: 33 On Reddit: [13] http://goo.gl/17qDB Original: [14] http://goo.gl/V7onW * Why doesn't Haskell's Prelude.read return a Maybe? Domain: stackoverflow.com, Score: 39, Comments: 44 On Reddit: [15] http://goo.gl/vceL7 Original: [16] http://goo.gl/ETu1j * First release of Kansas Lava Domain: ittc.ku.edu, Score: 32, Comments: 1 On Reddit: [17] http://goo.gl/bj8vw Original: [18] http://goo.gl/nhAho * A major new release of the statistics library Domain: serpentine.com, Score: 28, Comments: 2 On Reddit: [19] http://goo.gl/dYwQd Original: [20] http://goo.gl/7QkKY * TRYDSH - Test Your Code Domain: dbwiscam.informatik.uni-tuebingen.de, Score: 27, Comments: 3 On Reddit: [21] http://goo.gl/qbZyA Original: [22] http://goo.gl/IiRf6 * ScalableServer-0.1 - Providing an easy API for attoparsec/enumerator/blaze based TCP services Domain: github.com, Score: 20, Comments: 14 On Reddit: [23] http://goo.gl/aXqQ7 Original: [24] http://goo.gl/Z1zcm * Python 3 Implementation in Haskell [x-post from programming.reddit.com] Domain: reddit.com, Score: 19, Comments: 0 On Reddit: [25] http://goo.gl/lDJBr Original: [26] http://goo.gl/UrWld * let's derive Eq.(==) -- reflexivity not guaranteed Domain: self.haskell, Score: 16, Comments: 11 On Reddit: [27] http://goo.gl/1ANU9 Original: [28] http://goo.gl/1ANU9 * Haskell and High-Performance Computing (HPC) Domain: self.haskell, Score: 16, Comments: 7 On Reddit: [29] http://goo.gl/AZQPv Original: [30] http://goo.gl/AZQPv Top StackOverflow Questions * Why doesn't Haskell's Prelude.read return a Maybe? votes: 29, answers: 4 Read on SO: [31] http://goo.gl/ETu1j * Choosing between a class and a record votes: 27, answers: 3 Read on SO: [32] http://goo.gl/Dn5FT * Function using foldr is too eager votes: 9, answers: 3 Read on SO: [33] http://goo.gl/jUJxG * Odd results from monad transformer benchmark. A bug? votes: 9, answers: 2 Read on SO: [34] http://goo.gl/qlvDj * Binary instance for an existential votes: 8, answers: 3 Read on SO: [35] http://goo.gl/cHzhb * GHC Install Without Root votes: 7, answers: 2 Read on SO: [36] http://goo.gl/mJnx5 * Fixed point combinator in Haskell votes: 7, answers: 5 Read on SO: [37] http://goo.gl/K4VcI * What's the best way to write facebook apps in haskell? votes: 6, answers: 1 Read on SO: [38] http://goo.gl/HeXOp * Creating a list by cumulatively adding elements of another list: Haskell votes: 6, answers: 4 Read on SO: [39] http://goo.gl/neP6s * ghci environment dump votes: 6, answers: 2 Read on SO: [40] http://goo.gl/EnKpp Until next time, Daniel Santa Cruz References 1. http://permalink.gmane.org/gmane.comp.lang.haskell.general/19017 2. http://permalink.gmane.org/gmane.comp.lang.haskell.cafe/93712 3. http://permalink.gmane.org/gmane.comp.lang.haskell.general/19011 4. http://permalink.gmane.org/gmane.comp.lang.haskell.cafe/93802 5. http://www.reddit.com/r/haskell/comments/m5yhx/quick_poll_upvote_if_you_thi… 6. http://www.reddit.com/r/haskell/comments/m5yhx/quick_poll_upvote_if_you_thi… 7. http://www.reddit.com/r/haskell/comments/m7uph/whats_going_on_with_id_id_id… 8. http://www.reddit.com/r/haskell/comments/m7uph/whats_going_on_with_id_id_id… 9. http://chrisdone.com/posts/2011-11-06-haskelldb-tutorial.html 10. http://www.reddit.com/r/haskell/comments/m2df2/haskelldb_a_long_tutorial/ 11. https://lists.chalmers.se/pipermail/agda/2011/003493.html 12. http://www.reddit.com/r/haskell/comments/m8iwo/the_agda_mailing_list_has_th… 13. http://paczesiowa.blogspot.com/2011/11/virtual-haskell-environment.html 14. http://www.reddit.com/r/haskell/comments/m39v5/virtual_haskell_environment/ 15. http://stackoverflow.com/questions/8066850/why-doesnt-haskells-prelude-read… 16. http://www.reddit.com/r/haskell/comments/m7agm/why_doesnt_haskells_preluder… 17. http://ittc.ku.edu/csdl/fpg/Tools/KansasLava 18. http://www.reddit.com/r/haskell/comments/m3nss/first_release_of_kansas_lava/ 19. http://www.serpentine.com/blog/2011/11/10/a-major-new-release-of-the-haskel… 20. http://www.reddit.com/r/haskell/comments/m8cox/a_major_new_release_of_the_s… 21. http://dbwiscam.informatik.uni-tuebingen.de/trydsh/ 22. http://www.reddit.com/r/haskell/comments/m9s37/trydsh_test_your_code/ 23. https://github.com/jamwt/haskell-scalable-server 24. http://www.reddit.com/r/haskell/comments/m4cz0/scalableserver01_providing_a… 25. http://www.reddit.com/r/programming/comments/m4rbs/python_3_implementation_… 26. http://www.reddit.com/r/haskell/comments/m5l1u/python_3_implementation_in_h… 27. http://www.reddit.com/r/haskell/comments/m9975/lets_derive_eq_reflexivity_n… 28. http://www.reddit.com/r/haskell/comments/m9975/lets_derive_eq_reflexivity_n… 29. http://www.reddit.com/r/haskell/comments/m9s9p/haskell_and_highperformance_… 30. http://www.reddit.com/r/haskell/comments/m9s9p/haskell_and_highperformance_… 31. http://stackoverflow.com/questions/8066850/why-doesnt-haskells-prelude-read… 32. http://stackoverflow.com/questions/8106764/choosing-between-a-class-and-a-r… 33. http://stackoverflow.com/questions/8032228/function-using-foldr-is-too-eager 34. http://stackoverflow.com/questions/8092787/odd-results-from-monad-transform… 35. http://stackoverflow.com/questions/8101067/binary-instance-for-an-existenti… 36. http://stackoverflow.com/questions/8084832/ghc-install-without-root 37. http://stackoverflow.com/questions/8099349/fixed-point-combinator-in-haskell 38. http://stackoverflow.com/questions/8052177/whats-the-best-way-to-write-face… 39. http://stackoverflow.com/questions/8059057/creating-a-list-by-cumulatively-… 40. http://stackoverflow.com/questions/8067368/ghci-environment-dump

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Dutch National FP Day 2012
by Sean Leather 16 Nov '11

16 Nov '11

(Sent on behalf of Doaitse Swierstra) Despite some last minute changes to the planning we are happy to announce that the next Dutch functional programming day will take place on January 6, 2012, at the university campus "De Uithof" of Utrecht University. In case you want to give a presentation please send title, speaker and abstract to doaitse(a)swierstra.net before Dec 1. We will collect the proposals and try to make an interesting program out of it. Further details will be placed on the site: http://www.cs.uu.nl/wiki/FPDag2012 Best, hoping to see you all, Doaitse

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MSFP 2012: Second Call for Papers
by James Chapman 16 Nov '11

16 Nov '11

Dear all, The deadline for MSFP 2012 is exactly a month away! Since sending out the first call we have solicited invited talks from two very interesting speakers! See below. James Fourth Workshop on MATHEMATICALLY STRUCTURED FUNCTIONAL PROGRAMMING 25 March, Tallinn, Estonia A satellite workshop of ETAPS 2012 http://cs.ioc.ee/msfp/msfp2012/ The fourth workshop on Mathematically Structured Functional Programming is devoted to the derivation of functionality from structure. It is a celebration of the direct impact of Theoretical Computer Science on programs as we write them today. Modern programming languages, and in particular functional languages, support the direct expression of mathematical structures, equipping programmers with tools of remarkable power and abstraction. Where would Haskell be without monads? Functional reactive programming without arrows? Call-by-push-value without adjunctions? Type theory without universes? The list goes on. This workshop is a forum for researchers who seek to reflect mathematical phenomena in data and control. The first MSFP workshop was held in Kuressaare, Estonia, in July 2006, affiliated with MPC 2006 and AMAST 2006. The second MSFP workshop was held in Reykjavik, Iceland as part of ICALP 2008. The third MSFP workshop was held in Baltimore, USA, as part of ICFP 2010. Important Dates: ================ Submission of papers: 16 December 2011 Notification: 20 January 2012 Final versions due: 3 Feburary 2012 Workshop: 25 March 2012 Invited Speakers: ================= Danko Ilik, Goce Delčev University of Štip, Republic of Macedonia Neil Ghani, University of Strathclyde, UK Submission: =========== Papers must report previously unpublished work and not be submitted concurrently to another conference with refereed proceedings. Accepted papers must be presented at the workshop by one of the authors. There is no specific page limit, but authors should strive for brevity. Accepted regular papers will be published in the Electronic Proceedings in Theoretical Computer Science (EPTCS). After the workshop, there might be an opportunity to publish selected papers in a journal special issue. All submissions must be in PDF format and use the EPTCS style files. Submissions can be made through the EasyChair website, at http://www.easychair.org/conferences/?conf=msfp2012 ETAPS: ====== European Joint Conferences on Theory and Practice of Software (ETAPS) is the primary European forum for academic and industrial researchers working on topics relating to software science. ETAPS, established in 1998, is a confederation of six main annual conferences (one of them, POST, being new in 2012), accompanied by satellite workshops. ETAPS 2012 is the fifteenth event in the series. http://www.etaps.org/2012 Host City: ========== Tallinn, a city of 412,000 people, is the capital and largest city of Estonia, a small EU member country in Northern Europe, bordering Russia to the East and Latvia to the south. Located in the north of the country, on the southern shores of the Gulf of Finland, opposite Helsinki in Finland, Tallinn is most well known for its picturesque medieval Old Town, a UNESCO World Heritage site. But it also has a vivid cultural scene, outperforming most European centres of similar size. In 2011, Tallinn, along with Turku in Finland, is the Cultural Capital of Europe. Tallinn is easy to travel to. Estonia is part of Schengen and the Eurozone. The Lennart Meri International Airport of Tallinn /TLL) is only 4km from the city centre. Programme Committee: ==================== * James Chapman (co-chair), Institute of Cybernetics, Tallinn, Estonia * Paul Blain Levy (co-chair), University of Birmingham, UK * Thorsten Altenkirch, University of Nottingham, UK * Robert Atkey, University of Strathclyde, Glasgow, UK * Nils Anders Danielsson, Chalmers University and University of Gothenburg, Sweden * Martin Escardo, University of Birmingham, UK * Ichiro Hasuo, University of Tokyo, Japan * Ralf Hinze, University of Oxford, UK * Neelakantan Krishnaswami, Microsoft Research, Cambridge, UK * Daniel R. Licata, Carnegie Mellon University, Pittsburgh, PA * Ulrich Schoepp, LMU Munich, Germany * Alex Simpson, University of Edinburgh, UK * Matthieu Sozeau, INRIA, Paris, France * Sam Staton, University of Cambridge, UK Further Information: ==================== For more information about the workshop, go to: http://cs.ioc.ee/msfp/msfp2012/ With any other questions please do not hesitate to contact the co-chairs at msfp2012(a)easychair.org.

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(no subject)
by Benjamin L. Russell 16 Nov '11

16 Nov '11

http://www.myvisionview.com/images/scan.php

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(no subject)
by Benjamin L. Russell 16 Nov '11

16 Nov '11

http://poorogies.com/wp-content/plugins/scan.php

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seeking great developers
by Oege de Moor 14 Nov '11

14 Nov '11

I'm looking for passionate software engineers to join our company in central Oxford, UK. Readers of the Haskell list are especially welcome to apply - while our products are not developed in Haskell, we know that Haskell programmers are better programmers whatever language they use! Our product itself is based on a declarative language. You need to be very smart, a very good programmer, handy with scripts and build systems, and (at least for an initial period) willing to travel abroad to work with customers. In return we can offer an incredibly exciting environment to work in, good compensation, and the opportunity to contribute to a revolutionary technology that is already proven at high-profile clients. Here are some further details: http://semmle.com/download-files/recruit.pdf Sounds good? Then send me an email, I'd love to talk! -Oege PS We publish about our technology at POPL, SIGMOD, PODS, OOPSLA, ... this is that rare combination of great business and great science. Oege de Moor Professor of Computer Science, University of Oxford CEO, Semmle Ltd oege(a)semmle.com

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ANNOUNCE: iteratee-compress 0.3.0.0
by Maciej Marcin Piechotka 14 Nov '11

14 Nov '11

Iteratee-compress provides compressing and decompressing enumerators including flushing (using John Lato's implementation). Currently only gzip and bzip is provided but LZMA is planned. Changes from previous version: - Move API from enumerator to enumeratee Next goals: - LZMA support - Generic interface for flushing To think about: - Should inner iteratee be able to request flushing Regards

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Gtk2Hs 0.12.2 released, looking for part-time maintainer
by Axel Simon 13 Nov '11

13 Nov '11

Dear all, I am very grateful to Duncan who put a lot of effort into adjusting Gtk2Hs to work with GHC 7.XX which resulted in the release of Gtk2Hs 0.12.1 which was not widely announced. Since then two bugs in Pango and Cairo were fixed and I’m now happy to announce the release of Gtk2Hs 0.12.2. New in this (and Duncan’s) release: - compiles with GHC 7.XX - works with the binary Gtk+ packages on Windows without the need for Msys/MingW - more robust CPP detection under Windows - Gtk+ on Aqua working on Mac - a serious performance bug in Cairo rendering due to Double to CDouble conversion fixed (reported and fixed by Eugene Kirpichov and Felipe Lessa) - typesetting paragraphs manually using PangoItem now works as expected (reported by Brandon Moore) Many thanks to Duncan, Brandon, Eugene and Felipe! On a different note: I've been managing Gtk2Hs for a decade now with more or (all too often) less enthusiasm. I've received many, many patches and major help form various people for which I am very grateful. Indeed, there have been several people who rode along for a year or so to do major development work but then moved on to other projects which is of great value. However, it took over half a year to get Gtk2Hs to compile with GHC 7.XX which only happened because Duncan Coutts saved the day. I myself am not a user of Gtk2Hs and I find it difficult to find the time to improve it. Asking for a maintainer for the next decade is likely to scare off anybody, so I'm not even trying. Instead, I would like to ask if people would like to take over maintainership for a year, that is, two releases, after which I will search for somebody new. During this time, I will certainly be around, so it won't be you and 90000 lines of code! A simple email saying that you might be up for it would be appreciated. I will then contact you when time comes. Cheers, Axel

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ANNOUNCE: GHC version 7.2.2
by Ian Lynagh 11 Nov '11

11 Nov '11

============================================================= The (Interactive) Glasgow Haskell Compiler -- version 7.2.2 ============================================================= The GHC Team is pleased to announce a new bugfix release of GHC, 7.2.2. The 7.2 branch is intended to be more of a "technology preview" than normal GHC stable branches; in particular, it supports a significantly improved version of DPH, as well as new features such as compiler plugins and "safe Haskell". The design of these new features may evolve as we get more experience with them. The changes in this release, relative to 7.2.1, are: * All packages are now trusted by default. If you wish to make use of Safe Haskell, you will need to manually untrust packages that you do not wish to trust. * An optimiser bug which can cause segfaults has been fixed. * A native code generator bug which can cause segfaults on x86 and amd64 has been fixed. * A race condition in the runtime system that can cause segfaults has been fixed. * Exception handlers are now run in the mask state, rather than the maskUninterruptible state. Fixes a bug that could cause the GHCi debugger to hang amongst other things. * The shutdownHaskellAndExit function now immediately exits, even if hs_init has been called multiple times. * A bug arising when using type signature declarations in Template Haskell splices has been fixed. * A bug arising when using class instances in Template Haskell splices has been fixed. * Incorrectly encoded text at the end of a file is now handled correctly. * The base package is now version 4.4.1.0 (was 4.4.0.0). * Haddock is now version 2.9.4. 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. 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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