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LINEARITY 2012 - Call for papers
by Mário Florido 21 Oct '11

21 Oct '11

Call for Papers Second International Workshop on Linearity http://sites.google.com/site/linearity2012/ Tallinn, Estonia 1 April 2012 An associated event of ETAPS 2012, European Joint Conferences on Theory and Practice of Software =================================================================== With the urge for more robust, verifiable and optimised programming languages, the interest for linearity in order to have more control on computational resources is increasing in several areas of Computer Science, both in the theoretical side: with work on proof technology, complexity classes and more recently quantum computation, and in the practical side: work on program analysis, expressive operational semantics, linear languages, and techniques for program transformation, update analysis and efficient implementation. The aim of this workshop is to bring together researchers who are currently developing theory and applications of linear calculi, to foster their interaction and provide a forum for presenting new ideas and work in progress, and enable newcomers to learn about current activities in this area. LINEARITY 2012 will be a one-day satellite event of ETAPS 2012. Topics of interest include foundational calculus, models, applications to programming languages and systems. This includes (but is not limited to): * Linear types: session types, etc * Linear calculi; * Functional calculi: lambda-calculus, rho-calculus, term and graph rewriting; * Object calculi; * Interaction-based systems: interaction nets, games; * Concurrent models: process calculi, action graphs; * Calculi expressing locality, mobility, and active data; * Quantum computational models; * Biological or chemical models of computation; Important Dates --------------- * 16 December 2011: Abstract deadline (registration with easychair) * 22 December 2011: Submission deadline * 20 January 2012: Author notification * 3 February 2012: Deadline for final versions of accepted papers * 1 April 2012: Workshop Submission and Publication -------------------------- Authors are invited to submit a short paper (5-7 pages). Preliminary proceedings will be available at the workshop. Papers should be written in English, and submitted in PostScript or PDF format, using the EPTCS style files. Submission is through the Easychair website: https://www.easychair.org/account/signin.cgi?timeout=1;conf=linearity2012 After the workshop authors are invited to submit a revised version (12 pages) of their presentation. After a second round of refereeing, accepted contributions will appear in an issue of Electronic Proceedings in Theoretical Computer Science (www.eptcs.org) Authors and participants will also be invited to submit an article to a special issue of a Journal. Programme Committee ------------------- * Sandra Alves (co-chair) * Maribel Fernández * Mário Florido * Martin Hofmann * Ian Mackie (co-chair) * Simone Martini * Valeria de Paiva * Simona Ronchi Della Rocca * Alex Simpson Contact ------- Sandra Alves: sandra(a)dcc.fc.up.pt Ian Mackie: iancmackie(a)gmail.com

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Faculty Fellowships
by Simon Peyton-Jones 21 Oct '11

21 Oct '11

Friends Microsoft Research is inviting nominations for its Faculty Fellowship program, starting on September 30, 2011. This program recognizes and supports exceptional early-career faculty engaged in innovative computing research. The objective is to stimulate and support the research of promising individuals who have the potential to make a profound impact on the state-of-the-art in their research disciplines and to become future thought leaders. The award is substantial -- typically enough to fund a faculty salary for a couple of years. Applications by 31 October. Further information is available at http://research.microsoft.com/en-us/collaboration/awards/msrff.aspx, questions regarding eligibility etc. can be directed to flshph(a)microsoft.com<mailto:flshph@microsoft.com>. Simon

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ICFP 2012: Call for workshops and co-located events
by Wouter Swierstra 21 Oct '11

21 Oct '11

CALL FOR WORKSHOP AND CO-LOCATED EVENT PROPOSALS ICFP 2012 17th ACM SIGPLAN International Conference on Functional Programming September 9 - 15, 2012 Copenhagen, Denmark http://icfpconference.org/icfp2012/ The 17th ACM SIGPLAN International Conference on Functional Programming will be held in Copenhagen, Denmark on September 9-15, 2012. ICFP provides a forum for researchers and developers to hear about the latest work on the design, implementations, principles, and uses of functional programming. Proposals are invited for workshops (and other co-located events, such as tutorials) to be affiliated with ICFP 2012 and sponsored by SIGPLAN. These events should be more informal and focused than ICFP itself, include sessions that enable interaction among the attendees, and foster the exchange of new ideas. The preference is for one-day events, but other schedules can also be considered. The workshops are scheduled to occur on September 9 (the day before ICFP) and September 13-15 (the three days after ICFP). ---------------------------------------------------------------------- Submission details Deadline for submission: November 19, 2011 Notification of acceptance: December 17, 2011 Prospective organizers of workshops or other co-located events are invited to submit a completed workshop proposal form in plain text format to the ICFP 2012 workshop co-chairs (Patrik Jansson and Gabriele Keller), via email to icfp12-workshops at cse.unsw.edu.au by November 19, 2011. (For proposals of co-located events other than workshops, please fill in the workshop proposal form and just leave blank any sections that do not apply.) Please note that this is a firm deadline. Organizers will be notified if their event proposal is accepted by December 17, 2011, and if successful, depending on the event, they will be asked to produce a final report after the event has taken place that is suitable for publication in SIGPLAN Notices. The proposal form is available at: http://www.icfpconference.org/icfp2012/icfp12-workshops-form.txt Further information about SIGPLAN sponsorship is available at: http://acm.org/sigplan/sigplan_workshop_proposal.htm ---------------------------------------------------------------------- Selection committee The proposals will be evaluated by a committee comprising the following members of the ICFP 2012 organizing committee, together with the members of the SIGPLAN executive committee. Workshop Co-Chair: Gabriele Keller (University of New South Wales) Workshop Co-Chair: Patrik Jansson (Chalmers University of Technology) General Chair : Peter Thiemann (University of Freiburg) Program Chair: Robby Findler (Northwestern University) ---------------------------------------------------------------------- Further information Any queries should be addressed to the workshop co-chairs (Patrik Jansson and Gabriele Keller), via email to icfp12-workshops at cse.unsw.edu.au

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Haskell Weekly News: Issue 204
by Daniel Santa Cruz 20 Oct '11

20 Oct '11

Welcome to issue 204 of the HWN, a newsletter covering developments in the Haskell community. This release covers the week of October 9 to 15, 2011. You can find the HTML version of this issue at: http://contemplatecode.blogspot.com/2011/10/haskell-weekly-news-issue-204.h… New and Updated Projects * lhs2tex-hl (Alessandro Vermeulen; 1.4.3) Upgraded package builds with GHC 7.2.x. [1] http://goo.gl/2VQmw * global-variables (Jean-Marie Gaillourdet; 1.0) A package providing a global namespace for IORefs, MVars, and TVars. [2] http://goo.gl/B9YPO * vector-bytestring (Bas van Dijk; 0.0.0.0) "The very ambitious goal of this package is that it will eventually replace our beloved bytestring package. By basing this package on vector, we can benefit from all the optimizations (like stream-fusion!) in that library." [3] http://goo.gl/SAUiF * simple-actors (Brandon Simmons; 0.1.0) An eDSL library for actor model concurrency. [4] http://goo.gl/f9hvu * ircbot (Jeremy Shaw; 0.1.1) ... "becase that's what Haskell really needs -- another irc bot library." [5] http://goo.gl/A252O Quotes of the Week * Pseudonym: A type is a collection of values, and a class is a collection of types. * xplat: you just need to write a corresponding set of modules for well-hung coinduction * Porges: State is stored in spacesuits. [via: reddit] [djahandarie] Group projects are stupid [shachaf] Try a semigroup project sometime. You need to lose your identity. Top Reddit Stories * shqq: Embedding shell commands in Haskell code Domain: mainisusuallyafunction.blogspot.com, Score: 51, Comments: 5 On Reddit: [6] http://goo.gl/b7zj5 Original: [7] http://goo.gl/9LVhi * Shooting yourself in the foot with Haskell Domain: haskell.org, Score: 47, Comments: 7 On Reddit: [8] http://goo.gl/C1VJY Original: [9] http://goo.gl/yGceC * Why learn Haskell? [PDF slides] Domain: ugcs.net, Score: 32, Comments: 31 On Reddit: [10] http://goo.gl/Coml0 Original: [11] http://goo.gl/MgVwe * How to beat the CAP theorem - purely functional databases Domain: nathanmarz.com, Score: 28, Comments: 11 On Reddit: [12] http://goo.gl/s1TjI Original: [13] http://goo.gl/HQvlK * Yo /r/haskell, I heard you like monads... Domain: self.haskell, Score: 25, Comments: 26 On Reddit: [14] http://goo.gl/xSbj7 Original: [15] http://goo.gl/xSbj7 * FRP and Haskell being used for physiological experimentation and analysis - Haskell-cafe Domain: haskell.org, Score: 21, Comments: 3 On Reddit: [16] http://goo.gl/XxE3y Original: [17] http://goo.gl/fMBMR * Composing a list of Enumeratees Domain: permalink.gmane.org, Score: 19, Comments: 14 On Reddit: [18] http://goo.gl/fwcY1 Original: [19] http://goo.gl/V2bgc * hp2pretty-0.5 released - Now with go faster stripes! Domain: claudiusmaximus.goto10.org, Score: 19, Comments: 0 On Reddit: [20] http://goo.gl/csnhI Original: [21] http://goo.gl/18myY * FRP - How to deal with concurrent external events? Domain: apfelmus.nfshost.com, Score: 16, Comments: 0 On Reddit: [22] http://goo.gl/HqgyJ Original: [23] http://goo.gl/2QYcU * Talk (by factis research) about developing commercial software in Haskell Domain: factisresearch.blogspot.com, Score: 16, Comments: 5 On Reddit: [24] http://goo.gl/iyKDs Original: [25] http://goo.gl/RSHLE * A French community for Haskell Domain: alpmestan.wordpress.com, Score: 15, Comments: 0 On Reddit: [26] http://goo.gl/KSy83 Original: [27] http://goo.gl/rF4Zs * VirtuaHac: The Completely Online Hackathon Domain: haskell.org, Score: 15, Comments: 8 On Reddit: [28] http://goo.gl/3Ej9Z Original: [29] http://goo.gl/wj05N * kmeans-vector: kmeans clustering algorithm implementation Domain: hackage.haskell.org, Score: 14, Comments: 0 On Reddit: [30] http://goo.gl/DcvcO Original: [31] http://goo.gl/df48V Top StackOverflow Questions * Meaning of Haskell exceptions votes: 19, answers: 2 Read on SO: [32] http://goo.gl/Aa2H9 * Are there pronounceable names for common Haskell operators? votes: 19, answers: 2 Read on SO: [33] http://goo.gl/qr2QN * Space leak only in certain cases in GHC interpreter when doing: concat <some list> !! n votes: 18, answers: 0 Read on SO: [34] http://goo.gl/y7W50 * Type theory: type kinds votes: 18, answers: 3 Read on SO: [35] http://goo.gl/ne79b * Why is the minimalist, example Haskell quicksort not a “true” quicksort? votes: 16, answers: 6 Read on SO: [36] http://goo.gl/Zldpx * Space leaks, and Writers, and Sums (oh my!) votes: 15, answers: 3 Read on SO: [37] http://goo.gl/Lt62v * Can this functionality be implemented with Haskell's type system? votes: 14, answers: 3 Read on SO: [38] http://goo.gl/4aV7G * Total function of type (forall n . Maybe (f n)) -> Maybe (forall n . (f n)) votes: 14, answers: 3 Read on SO: [39] http://goo.gl/qUyYR * Standard web server interface equivalent to WSGI/Rack for Haskell votes: 9, answers: 2 Read on SO: [40] http://goo.gl/9fWNq * Automatic lifting of infix operators to monadic infix operators votes: 8, answers: 3 Read on SO: [41] http://goo.gl/jDQWC Until next time, Daniel Santa Cruz References 1. http://permalink.gmane.org/gmane.comp.lang.haskell.cafe/93087 2. http://permalink.gmane.org/gmane.comp.lang.haskell.general/18977 3. http://permalink.gmane.org/gmane.comp.lang.haskell.general/18975 4. http://permalink.gmane.org/gmane.comp.lang.haskell.cafe/93016 5. http://permalink.gmane.org/gmane.comp.lang.haskell.cafe/92986 6. http://mainisusuallyafunction.blogspot.com/2011/10/shqq-embedding-shell-com… 7. http://www.reddit.com/r/haskell/comments/l86s6/shqq_embedding_shell_command… 8. http://www.haskell.org/haskellwiki/Shooting_your_self_in_the_foot 9. http://www.reddit.com/r/haskell/comments/l6smh/shooting_yourself_in_the_foo… 10. http://ugcs.net/~keegan/talks/why-learn-haskell/talk.pdf 11. http://www.reddit.com/r/haskell/comments/la9ey/why_learn_haskell_pdf_slides/ 12. http://nathanmarz.com/blog/how-to-beat-the-cap-theorem.html 13. http://www.reddit.com/r/haskell/comments/lb66h/how_to_beat_the_cap_theorem_… 14. http://www.reddit.com/r/haskell/comments/ldu36/yo_rhaskell_i_heard_you_like… 15. http://www.reddit.com/r/haskell/comments/ldu36/yo_rhaskell_i_heard_you_like… 16. http://www.haskell.org/pipermail/haskell-cafe/2011-October/095857.html 17. http://www.reddit.com/r/haskell/comments/l6yep/frp_and_haskell_being_used_f… 18. http://permalink.gmane.org/gmane.comp.lang.haskell.cafe/92928 19. http://www.reddit.com/r/haskell/comments/la4at/composing_a_list_of_enumerat… 20. http://claudiusmaximus.goto10.org/cm/2011-10-15_hp2pretty-0.5_released.html 21. http://www.reddit.com/r/haskell/comments/lcw7n/hp2pretty05_released_now_wit… 22. http://apfelmus.nfshost.com/blog/2011/10/11-frp-concurrent-events.html 23. http://www.reddit.com/r/haskell/comments/l9hgz/frp_how_to_deal_with_concurr… 24. http://factisresearch.blogspot.com/2011/10/yesterday-i-gave-talk-at-haskell… 25. http://www.reddit.com/r/haskell/comments/l9zq3/talk_by_factis_research_abou… 26. http://alpmestan.wordpress.com/2011/10/09/a-french-community-for-haskell/ 27. http://www.reddit.com/r/haskell/comments/l6eqx/a_french_community_for_haske… 28. http://haskell.org/haskellwiki/VirtuaHac 29. http://www.reddit.com/r/haskell/comments/l6knx/virtuahac_the_completely_onl… 30. http://hackage.haskell.org/package/kmeans-vector-0.1 31. http://www.reddit.com/r/haskell/comments/l67mi/kmeansvector_kmeans_clusteri… 32. http://stackoverflow.com/questions/7704999/meaning-of-haskell-exceptions 33. http://stackoverflow.com/questions/7746894/are-there-pronounceable-names-fo… 34. http://stackoverflow.com/questions/7707661/space-leak-only-in-certain-cases… 35. http://stackoverflow.com/questions/7752452/type-theory-type-kinds 36. http://stackoverflow.com/questions/7717691/why-is-the-minimalist-example-ha… 37. http://stackoverflow.com/questions/7720929/space-leaks-and-writers-and-sums… 38. http://stackoverflow.com/questions/7705119/can-this-functionality-be-implem… 39. http://stackoverflow.com/questions/7720108/total-function-of-type-forall-n-… 40. http://stackoverflow.com/questions/7700619/standard-web-server-interface-eq… 41. http://stackoverflow.com/questions/7742625/automatic-lifting-of-infix-opera…

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haskell.org committee: Call for nominations
by Ganesh Sittampalam 18 Oct '11

18 Oct '11

Dear Haskellers, The first year of the haskell.org committee is drawing to a close and it is therefore time to seek replacements for those members whose term is expiring. This year two members are retiring, Ian Lynagh and Malcolm Wallace. The rest of the committee would like to thank them for their excellent service, both from the time before the committee was formed when they amongst the people who handled similar responsibilities on a more informal basis, and over the last year. To nominate yourself, please send an e-mail to committee at haskell.org by 29 October 2011. The retiring members are eligible to re-nominate themselves. Please feel free to include any information about yourself that you think will help us to make a decision. Being a member of the committee does not require a significant amount of time, but committee members should aim to be responsive during discussions when the committee is called upon to make a decision. More details about the committee's roles and responsibilities are on http://www.haskell.org/haskellwiki/Haskell.org_committee If you have any questions about the process, please feel free to e-mail us at committee at haskell.org or to contact one of us individually. We will shortly also be producing a report and accounts covering the first year of operation of the committee. Regards, Ganesh On behalf of the haskell.org committee

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GPCE 2011 Call for Participation
by Chang Hwan Peter Kim 15 Oct '11

15 Oct '11

------------------------------------------------------------------------ CALL FOR PARTICIPATION Tenth International Conference on Generative Programming and Component Engineering (GPCE 2011) October 22-23, 2011 Portland, Oregon, USA (collocated with SPLASH 2011) http://www.gpce.org http://twitter.com/GPCECONF Facebook: GPCE 2011 ------------------------------------------------------------------------ Last chance to register for GPCE 2011. The program features keynotes by Matthias Felleisen (Northeastern University) and Gary Shubert (Lockheed Martin Space Systems Company), 18 technical talks covering theoretical and practical aspects of generative and component based programming, and two tech talks by Olivier Danvy (University of Aarhus) and John Launchbury (Galois, Inc.). Registration: http://splashcon.org/2011/attending/registering GPCE SCOPE Generative and component approaches are revolutionizing software development just as automation and componentization revolutionized manufacturing. Key technologies for automating program development are Generative Programming for program synthesis, Component Engineering for modularity, and Domain-Specific Languages (DSLs) for compact problem-oriented programming notations. The International Conference on Generative Programming and Component Engineering is a venue for researchers and practitioners interested in techniques that use program generation and component deployment to increase programmer productivity, improve software quality, and shorten the time-to-market of software products. In addition to exploring cutting-edge techniques of generative and component-based software, our goal is to foster further cross-fertilization between the software engineering and the programming languages research communities. ORGANIZATION Chairs (chairs(a)gpce.org) General Chair: Ewen Denney (SGT/NASA Ames, USA) Program Chair: Ulrik Pagh Schultz (University of Southern Denmark) Publicity Chair: Chang Hwan Peter Kim (University of Texas, USA) Program Committee * Andrzej Wasowski (IT University of Copenhagen, Denmark) * Aniruddha Gokhale (Vanderbilt University, USA) * Bernd Fischer (University of Southampton, UK) * Bruno C. d. S. Oliveira (Seoul National University, Korea) * Christian Kaestner (Philipps Universitat Marburg, Germany) * Chung-Chieh Shan (Cornell University, USA) * Don Batory (University of Texas, USA) * Eli Tilevich (Virginia Tech, USA) * Eric Tanter (University of Chile, Chile) * Gorel Hedin (Lund University, Sweden) * Ina Schaefer (TU Braunschweig, Germany) * Jeremiah Willcock (Indiana University, USA) * Jeremy Siek (University of Colorado at Boulder, USA) * Jurgen Vinju (Centrum Wiskunde en Informatica, The Netherlands) * Lionel Seinturier (University of Lille, France) * Marjan Mernik (University of Maribor, Slovenia) * Mat Marcus (Canyonlands Software Design, USA) * Nicolas Loriant (Imperial College, France) * Ras Bodik (University of California at Berkeley, USA) * Robert Gluck (University of Copenhagen, Denmark) * Steffen Zschaler (King's College London, UK) * Tudor Girba (netstyle.ch, Switzerland) * Walter Binder (University of Lugano, Switzerland) * Yanhong A. Liu (State University of New York at Stony Brook, USA)

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ANNOUNCE: vector-bytestring-0.0.0.0
by Bas van Dijk 14 Oct '11

14 Oct '11

All your ByteString are belong to us... Hello, I'm pleased to announce the beta release of vector-bytestring. This library provides the type ByteString which is defined as a type synonym for a storable Vector of Word8s (from the vector package): type ByteString = Data.Vector.Storable.Vector Word8 It exports the same API as the bytestring package except that the module names are prefixed with: Data.Vector.Storable.ByteString instead of Data.ByteString. The very ambitious goal of this package is that it will eventually replace our beloved bytestring package. By basing this package on vector, we can benefit from all the optimizations (like stream-fusion!) in that library. We will also have just a single library to test, debug and optimize. TEST-SUITE I ported the bytestring test-suite to vector-bytestring. You can run it using: $ cabal configure --enable-tests; cabal build; cabal test All 54800 tests pass! Only one property doesn't hold: prop_show :: ByteString -> Bool prop_show x = show x == show (unpack x) This is because I don't provide a custom Show instance for ByteStrings but use the one from Vector which shows a vector like "fromList [1,2,3]" instead as "\SOH\STX\ETX" like bytestring does. Hopefully this is not a problem in practice. BENCHMARKS I added a criterion based benchmark-suite to vector-bytestring. It consists of over 600 benchmarks that cover almost every function in the library. Also included are benchmarks which benchmark the fusion capabilities of the library. Run it using: $ cabal configure -fbenchmark; cabal build; $ dist/build/bench/bench --help Unfortunately, bytestring still out performs us in lots of benchmarks. I believe the primary cause of this is that most functions are implemented using stream-fusion. This is highly efficient if you use a composition of these functions because they will all fuse into one single efficient loop. However if your program uses only a single function, the stream based implementation is often less efficient than an implementation that works directly on a mutable vector (like most functions in bytestring). So what we want is to use stream-fusion where possible but use mutable vectors when our program doesn't fuse. Fortunately, Roman Leshchinskiy (author of vector) has an idea how to do this: http://trac.haskell.org/vector/ticket/60 Because we don't beat bytestring in all cases yet you should consider this a beta-release and not use it in production code. INSTALLING $ cabal install vector-bytestring API DOCS http://hackage.haskell.org/package/vector-bytestring-0.0.0.0 DEVELOPING $ git clone https://github.com/basvandijk/vector-bytestring Regards, Bas

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CFP: FD-COMA 2012: Workshop on Feedback-Directed Compiler Optimization for Multi-Core Architectures
by Clemens Grelck 13 Oct '11

13 Oct '11

Call for Papers: FD-COMA 2012 Workshop on Feedback-Directed Compiler Optimization for Multi-Core Architectures 7th HiPEAC Conference Paris, France, Jan 23-25, 2012 http://www.project-advance.eu/2011/10/fd-coma-workshop-2012/ http://www.hipeac.org/conference FD-COMA is a one-day workshop during the 7th HiPEAC Conference in Paris, January 23-25, 2012. The workshop is loosely connected to the FP-7 project Advance, but we particularly welcome contributions from outside the project consortium. Scope: Feedback driven optimizations have long proven to be powerful instruments for achieving better hardware utilization, but the on-going multi-core/many-core revolution opens up a whole new realm of possible applications and variations of feedback-directed compiler optimization. The increasing hardware diversity of execution platforms and the likewise increasing hardware heterogeneity of individual execution platforms make compile time resource planning less and less feasible. Dynamic compilation techniques are required, instead, that adapt application programs to the actual hardware they are running on to make best use of it. Furthermore, the abundance of compute cores allows us to run feedback-directed compiler optimizations in parallel with an application itself and, thus, to adapt a running application to the hardware it is running on or to the data it is processing, to name just a few opportunities. This workshop aims at bringing people together that share an interest in the novel opportunities for feedback directed optimisations in the context of the emerging heterogeneous architectures. Main topics: + Feedback directed compiler optimization for multi-core architectures + Compiler representations for feedback information + Performance modeling for feedback, including statistical and constraint-based techniques + Performance measurement using feedback information + Exploiting feedback for heterogeneous multi-core systems + Adaptive, feedback-controlled runtime systems for multi-core architectures + Exploiting feedback information for energy savings FD-COMA welcomes submission of papers describing: + Experimental work + Industrial experience + Theoretical work + Software and hardware platforms + Work in progress all with respect to the above workshop topics Paper submission: Submitted papers must not have been published or simultaneously submitted elsewhere. The full manuscript should be at most 8 pages. Submit a PDF copy of your manuscript via EasyChair (not yet open). Each paper will receive a minimum of two reviews. Papers will be selected based on their originality, relevance, technical clarity and presentation. Authors of accepted papers must guarantee that their papers will be registered and presented at the workshop. Accepted papers will be made available at the workshop in electronic form. Important dates: Submission deadline: 4/11/2011 Notification of acceptance: 18/11/2011 Final version due: 13/1/2012 Workshop organizers: Kevin Hammond, University of St Andrews, United Kingdom Clemens Grelck, University of Amsterdam, Netherlands Sven-Bodo Scholz, Heriott-Watt University, United Kingdom -- ---------------------------------------------------------------------- Dr Clemens Grelck Science Park 904 University Lecturer 1098XH Amsterdam Netherlands University of Amsterdam Institute for Informatics T +31 (0) 20 525 8683 Computer Systems Architecture Group F +31 (0) 20 525 7490 Office C3.105 www.science.uva.nl/~grelck ----------------------------------------------------------------------

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Haskell Weekly News: Issue 203
by Daniel Santa Cruz 13 Oct '11

13 Oct '11

Welcome to issue 203 of the HWN, a newsletter covering developments in the Haskell community. This release covers the week of October 2 to 8, 2011. You can find a HTML version of this issue at: http://contemplatecode.blogspot.com/2011/10/haskell-weekly-news-issue-203.h… Announcements Eric Y. Kow has released the 6th issue of the Parallel Haskell Digest. [1] http://goo.gl/zyIWX Janis Voigtlander issued an invitation to send in contributions for the 21st edition of the Haskell Communities & Activities Report. The more the merrier! [2] http://www.mail-archive.com/haskell-cafe@haskell.org/msg93759.html New and Updated Projects * clientsession (Felipe Almeida Lessa; 0.7.3.1) Fix for security vulnerability. [3] http://goo.gl/Ot8d1 * hit (Vincent Hanquez) An implementation of low level git operations to read and write to a git repository. [4] http://goo.gl/bVxHw * OpenCL (Luis Cabellos; 1.0.1.3) An aparent fork of OpenCLRRaw package, done due to lack of updates from upstream. [5] http://goo.gl/bVxHw * HaTeX (Daniel Diaz Casanueva; 3) A set of combinators which allow you to build LaTeX code, following the LaTeX syntax in a type-safe manner. [6] http://goo.gl/zuW36 * Parsec (Antoine Latter; 3.1.2) A minor point release to the popular monadic combinator library. [7] http://goo.gl/Gx6Y3 * knob (John Millikin) Allows creation of memory-backed handles. [8] http://goo.gl/Jq7kl Quotes of the Week * heatsink: Maybe, (), and Bool go to the Lone Star Bar. The bouncer stops Maybe and says, "we don't serve your kind here." * DanBurton: correction - there will always be a job for programmers to write code to share pictures of cats * quicksilver: what we need is an adapter package any-lens which uses whichever lens package is available then we get potentially the disadvantages of all, without being able to guarantee the advantages of any. * mauke: Go too considered harmful * ddarius: isJust :: Maybe a -> Bool; isJust = unsafeCoerce * ddarius: Well when people say you need a PhD to program Haskell, you can point out that SPJ doesn't have a PhD. Top Reddit Stories * Is Haskell the Cure? Domain: mathias-biilmann.net, Score: 60, Comments: 60 On Reddit: [9] http://goo.gl/d84BE Original: [10] http://goo.gl/wMrH3 * Writing Functions With Many Nameless Parameters Domain: blog.atnnn.com, Score: 41, Comments: 6 On Reddit: [11] http://goo.gl/nLyGE Original: [12] http://goo.gl/uQkke * Want to help with the new hackage server? Jump in now... Domain: haskell.org, Score: 37, Comments: 0 On Reddit: [13] http://goo.gl/kV1gk Original: [14] http://goo.gl/i2Hbk * Slides from my talk on benchmarking and other random topics at IFL Domain: slideshare.net, Score: 32, Comments: 14 On Reddit: [15] http://goo.gl/SKJuH Original: [16] http://goo.gl/zRTwy * "OCaml For the Masses" article on Slashdot Domain: developers.slashdot.org, Score: 30, Comments: 49 On Reddit: [17] http://goo.gl/isVQ3 Original: [18] http://goo.gl/wlKaa * WebSockets support for WAI/Warp/Yesod: Thanks to Jasper's awesome work Domain: github.com, Score: 27, Comments: 6 On Reddit: [19] http://goo.gl/bpjUC Original: [20] http://goo.gl/bpjUC * A good explanation of the fixed point combinator in Haskell Domain: playingwithpointers.com, Score: 25, Comments: 9 On Reddit: [21] http://goo.gl/C8JmY Original: [22] http://goo.gl/zZnDO * ANNOUNCE: knob, a library for memory-backed handles Domain: haskell.org, Score: 24, Comments: 9 On Reddit: [23] http://goo.gl/JicDL Original: [24] http://goo.gl/xO2tY * HaTeX 3 is out! Domain: deltadiaz.blogspot.com, Score: 23, Comments: 17 On Reddit: [25] http://goo.gl/PVB9h Original: [26] http://goo.gl/aK8Tl * What should I use for web programming? Domain: self.haskell, Score: 22, Comments: 30 On Reddit: [27] http://goo.gl/74r1H Original: [28] http://goo.gl/74r1H * Practice for helping Java & C++ programmers learn Haskell: read programs with them, out loud Domain: cliffordbeshers.blogspot.com, Score: 21, Comments: 4 On Reddit: [29] http://goo.gl/6Cf2o Original: [30] http://goo.gl/P1pD1 * Creative partner request from a Haskell course's message board Domain: imgur.com, Score: 19, Comments: 5 On Reddit: [31] http://goo.gl/ZVWjs Original: [32] http://goo.gl/zW5Yf Top StackOverflow Questions * Clean and type-safe state machine implementation in a statically typed language? votes: 17, answers: 11 Read on SO: [33] http://goo.gl/GRI9p * What happens if an Enumerator tries to consume input? votes: 16, answers: 1 Read on SO: [34] http://goo.gl/bnTJD * Are there type signatures which Haskell can't verify? votes: 11, answers: 2 Read on SO: [35] http://goo.gl/0rfQe * Comparision of enumerator vs. iteratee package votes: 11, answers: 1 Read on SO: [36] http://goo.gl/iR9E1 * Will a value that has a type with class constraints actually be a function at run time? votes: 10, answers: 4 Read on SO: [37] http://goo.gl/o4zDC * Overloading (+) votes: 9, answers: 2 Read on SO: [38] http://goo.gl/Muxre * Strange type error in Haskell let-expression — what's the issue? votes: 9, answers: 3 Read on SO: [39] http://goo.gl/gKLSX * Haskell type declarations in 'where' — what's going on? votes: 8, answers: 2 Read on SO: [40] http://goo.gl/YIydy * Why is `http` in http-enumerator an Iteratee? votes: 8, answers: 1 Read on SO: [41] http://goo.gl/y3qQA * How to check for haskell package versions in ./configure? votes: 8, answers: 5 Read on SO: [42] http://goo.gl/o4EIu * Polynomial factorization in Haskell votes: 8, answers: 2 Read on SO: [43] http://goo.gl/nca2Z Until next time, Daniel Santa Cruz References 1. http://permalink.gmane.org/gmane.comp.lang.haskell.cafe/92911 2. http://www.mail-archive.com/haskell-cafe@haskell.org/msg93759.html 3. http://permalink.gmane.org/gmane.comp.lang.haskell.yesod/503 4. http://permalink.gmane.org/gmane.comp.lang.haskell.cafe/92871 5. http://permalink.gmane.org/gmane.comp.lang.haskell.cafe/92836 6. http://permalink.gmane.org/gmane.comp.lang.haskell.cafe/92908 7. http://permalink.gmane.org/gmane.comp.lang.haskell.general/18972 8. http://permalink.gmane.org/gmane.comp.lang.haskell.general/18974 9. http://mathias-biilmann.net/posts/2011/10/is-haskell-the-cure 10. http://www.reddit.com/r/haskell/comments/kza1y/is_haskell_the_cure/ 11. http://blog.atnnn.com/p/writing-haskell-functions-with-many-nameless-parame… 12. http://www.reddit.com/r/haskell/comments/kz8gx/writing_functions_with_many_… 13. http://www.haskell.org/pipermail/cabal-devel/2011-October/007803.html 14. http://www.reddit.com/r/haskell/comments/l3zye/want_to_help_with_the_new_ha… 15. http://www.slideshare.net/bos31337/pronk-like-you-mean-it 16. http://www.reddit.com/r/haskell/comments/l04nj/slides_from_my_talk_on_bench… 17. http://developers.slashdot.org/story/11/10/04/1557206/ocaml-for-the-masses 18. http://www.reddit.com/r/haskell/comments/l1jyt/ocaml_for_the_masses_article… 19. https://github.com/yesodweb/wai/blob/master/wai-websockets/Network/Wai/Hand… 20. http://www.reddit.com/r/haskell/comments/l2421/websockets_support_for_waiwa… 21. http://playingwithpointers.com/archives/590 22. http://www.reddit.com/r/haskell/comments/l4gmb/a_good_explanation_of_the_fi… 23. http://www.haskell.org/pipermail/haskell-cafe/2011-October/095896.html 24. http://www.reddit.com/r/haskell/comments/l5mwt/announce_knob_a_library_for_… 25. http://deltadiaz.blogspot.com/2011/10/hatex-3-first-release.html 26. http://www.reddit.com/r/haskell/comments/l38md/hatex_3_is_out/ 27. http://www.reddit.com/r/haskell/comments/l0fne/what_should_i_use_for_web_pr… 28. http://www.reddit.com/r/haskell/comments/l0fne/what_should_i_use_for_web_pr… 29. http://cliffordbeshers.blogspot.com/2011/10/conalelliott-re-what-resources.… 30. http://www.reddit.com/r/haskell/comments/l0k0w/practice_for_helping_java_c_… 31. http://imgur.com/mTxC4 32. http://www.reddit.com/r/haskell/comments/l3ah1/creative_partner_request_fro… 33. http://stackoverflow.com/questions/7699912/clean-and-type-safe-state-machin… 34. http://stackoverflow.com/questions/7683408/what-happens-if-an-enumerator-tr… 35. http://stackoverflow.com/questions/7644658/are-there-type-signatures-which-… 36. http://stackoverflow.com/questions/7674594/comparision-of-enumerator-vs-ite… 37. http://stackoverflow.com/questions/7659845/will-a-value-that-has-a-type-wit… 38. http://stackoverflow.com/questions/7646624/overloading 39. http://stackoverflow.com/questions/7662937/strange-type-error-in-haskell-le… 40. http://stackoverflow.com/questions/7635720/haskell-type-declarations-in-whe… 41. http://stackoverflow.com/questions/7638326/why-is-http-in-http-enumerator-a… 42. http://stackoverflow.com/questions/7645823/how-to-check-for-haskell-package… 43. http://stackoverflow.com/questions/7687792/polynomial-factorization-in-hask…

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ANN: global-variables-1.0
by Jean-Marie Gaillourdet 12 Oct '11

12 Oct '11

Hi, I am pleased to announce the first public release of global-variables. A package providing a global namespace for IORefs, MVars, and TVars. Hackage URL: http://hackage.haskell.org/package/global-variables-1.0 Source: http://bitbucket.org/jmg/global-variables/ Description: ---------------- 'Data.Global' provides a global namespace of 'IORef's, 'MVar's and 'TVar's. This namespace may be accessed in pure code. Yet reading and writing to those 'IORef's, 'MVar's and 'TVar's happens still in their respective monads. 'Data.Global' is designed to meet the following use cases: * Simplify the declaration of top-level mutable variables, by avoiding any pragmas as well as 'unsafePerformIO'. * Avoid having to pass references explicitly throughout the program in order to let distant parts communicate. * Enable a communication by convention scheme, where e.g. different libraries may communicate without code dependencies. * Simplify the "configuration problem" - at least for code in the IO monad. Note, that this library does not encourage sloppy software design by re-introducing all bad effects of global variables. Nevertheless, sometimes global variables are a suitable solution to a problem. In that case "Data.Global" simplifies and extends their handling significantly. Example: ------------- > module Main where > > import Data.Global > import Data.IORef > > counter :: IORef Int > counter = declareIORef "Main.counter" 0 > > main :: IO () > main = do > counter `writeIORef` 1 > readIORef counter >>= print Note absence of pragmas and of unsafePerformIO! Future Plans: ------------------ * Support discovery/traversal of existing variables * TemplateHaskell support to generate private and unique variable names. Regards, Jean

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