April 2015 - Haskell - Haskell.org

Haskell-related PhD Studentship at Kent
by Meng Wang 22 Mar '16

22 Mar '16

Dear Haskellers, I am seeking a PhD student on a Haskell-related project: http://www.cs.kent.ac.uk/research/studyingforaphd/phd-wang.html This would be a good opportunity for someone who is interested in applying Haskell ideas to real problems. The funding covers maintenance, EU student fees and research related expenses. But non-EU students are welcome to apply too. For Sep 2015 starting, the application deadline is 17 April 2015. If you are interested, please contact me at m.w.wang(a)kent.ac.uk<mailto:m.w.wang@kent.ac.uk>. Best wishes, Meng — Dr Meng Wang School of Computing University of Kent http://www.cs.kent.ac.uk/people/staff/mw516/

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ANNOUNCE: ioctl 0.0.1
by Maciej Piechotka 13 Sep '15

13 Sep '15

A package for type-safe I/O control. Currently only ioctl is supported. Currently simply a extract from my tuntap fork TODO: - Return the integer as well as structure (will break the API) - Port for Windows Network.Socket.IOCtl (as soon as I manage to setup some sane environment on this platform) - Wrapping around DeviceIoControl Example (in hsc): data NotRead = NotRead instance NotRead Int where ioctlReq _ = #const FIONREAD notRead s = ioctlsocket' s NotRead Regards

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CF STUDENT POSTERS for Innovations'15 (No registration fees), Dubai, November 01-03, 2015
by Nabeel Al-Qirim 22 Jun '15

22 Jun '15

CF STUDENT POSTERS for Innovations'15 (No registration fees), Dubai, November 01-03, 2015 IIT’15: The 11th International Conference on Innovations in Information Technology 2015 URL: http://www.it-innovations.ae/iit2015/posters.html The IIT’15 Student Poster and Demos Committee invites all undergraduate and graduate students to submit an extended (2 pages max.) abstract and to display it as a poster during the IIT’15. The poster topic should fall within the conference’s theme and tracks. SUBMISSION Extended abstracts should be sent to Dr. Nabeel Al-Qirim at nalqirim(a)uaeu.ac.ae. All students are encouraged to review their abstracts with their faculty advisers prior to submission. All accepted abstracts will be published by the IIT’15 proceedings. IMPORTANT DATES -Student Poster (Extended Paper) Submission May 30, 2015 -Notification of Student Poster acceptance July 15, 2015 -Camera ready Extended Paper and Poster material September 01, 2015 -Conference November 01-03, 2015 BEST STUDENT POSTER AWARDS There will be a competition for best student poster award at the IIT’15. This award will be given to recognize student excellence in research and presentation. CONTACT Queries should be directed to: Dr. Nabeel Al-Qirim at nalqirim(a)uaeu.ac.ae Thanks, Dr. Nabeel Al-Qirim IIT’15 Student Poster and Demos Chair College of Information Technology United Arab Emirates University P.O Box 15551 - Al Ain United Arab Emirates Tel: +971-3-7135531 Mobile: +971-507308705 Fax: +971-3-7672018 Email: nalqirim(a)uaeu.ac.ae Website: http://nalqirim.wix.com/nabeel-al-qirim Disclaimer:"The content of this email together with any attachments, statements and opinions expressed herein contains information that is confidential in nature and intended for the named addressee(s) only. If you are not the addressee of this email or you have received this message in error please notify the sender and delete the message and any associated files from your system, you have no right to copy, print, distribute or use this email or any of its attachments, or permit or disclose its contents to any other party in any way, except with the prior approval of the sender. In case of breach of what has been explained above, you will be held legally accountable." تنبيه: "إن محتوى هذا البريد الإلكتروني مع أي مرفقات والبيانات والآراء الواردة في هذه الوثيقة يحتوي على معلومات تعتبر سرية بطبيعتها وتستهدف المرسل اسمه (ق) فقط إذا لم تكن المرسل إليه من هذه الرسالة أو كنت قد تلقيت هذا. في رسالة الخطأ، الرجاء إبلاغ المرسل وحذف الرسالة وأية ملفات مرتبطة من النظام الخاص بك، ليس لديك الحق في نسخ أو طباعتها أو توزيعها أو استخدام هذا البريد الالكتروني أو أي من ملحقاته، أو السماح أو الكشف عن محتوياته إلى أي طرف آخر في بأي حال من الأحوال، إلا بموافقة مسبقة من المرسل، وفي حالة خرق ما سبق بيانه أعلاه، سوف تعقد لك مساءلة قانونيا" . www.uaeu.ac.ae<http://www.uaeu.ac.ae>

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Haskell Weekly News: Issue 322
by Semen Trygubenko / Семен Тригубен ко 21 May '15

21 May '15

New Releases 99 Haskell: A web service by Bram Hoskin Solve live Haskell coding problems based on H-99 in the browser to strengthen your understanding of the language. http://www.99haskell.org/ https://github.com/bramgg/99haskell/ Magic Cookies A commercial Android game is released that is written in Haskell using SDL2 for multimedia and the Arrowized Functional Reactive Programming DSL Yampa. The authors had to "escape their functional comfort zones and come up with smarter abstractions that mutable reality and performance demand". The game consists of 2K lines of code, of which 1K is game specific and 400 are Yampa code. The most complex parts were certain Yampa constructs (arrow-based, with lots of tupling/untupling). http://keera.co.uk/blog/2015/03/19/magic-cookies-released-google-play/ https://play.google.com/store/apps/details?id=uk.co.keera.games.magiccookies https://github.com/keera-studios/keera-hails https://github.com/ivanperez-keera/Yampa Discussion Finding a GHC bug by Neil Mitchell A write up of the hunt for bug #10176 http://neilmitchell.blogspot.it/2015/03/finding-ghc-bug.html https://ghc.haskell.org/trac/ghc/ticket/10176 What are your most persuasive examples of using Quickcheck? Quickcheck helped many people in a number of areas — compiler optimisations, date/time validation, regular expressions, encoding/decoding, topological sort, fuzzing HTTP APIs and even exhibiting classical voting paradox! Apart from the obvious benefit of helping to find big juicy bugs as well as valid but potentially harmless tiny bugs in edge cases that no-one cares about, Quickcheck can help attain enlightenment in the sense that spelling out Quickcheck properties in itself can be rewarding because this can reveal assumptions that have been made without realizing it. Roman Cheplyaka reminds us about SmallCheck and that it should be used instead of Quickcheck when one has a good idea about what depth is needed and when exhaustive search at that depth is affordable. https://www.reddit.com/r/haskell/comments/308ps6/what_are_your_most_persuas… http://stackoverflow.com/questions/20092191/how-much-should-one-control-the… What is the difference between free monads and free monoids? A comment by Edward Kmett. https://www.reddit.com/r/haskell/comments/2znhjk/what_is_the_difference_bet… Type-Checked Pseudo-Code Tom Ashworth argues that Haskell is an excellent tool for fleshing out ideas and prototyping solutions, and that it makes one generalize and shake out many conceptual bugs before concepts become code. https://phuu.net/2015/03/24/type-checked-pseudo-code.html Where does GHC spend most of it's time during compilation? Optimisation and codegen, it seems. Also, GHC compilation times went up substantially from version 7.6 to 7.8. https://www.reddit.com/r/haskell/comments/309430/where_does_ghc_spend_most_… Quotes of the Week "Haskell doesn't feel like code. It feels like a language for thinking in: it's expressive, terse and simple, especially as type-checked pseudo-code." (Tom Ashworth) https://phuu.net/2015/03/24/type-checked-pseudo-code.html "Well that's not in the spec. If you want to change the requirements you have to renegotiate the contract =P" (sccrstud92) https://www.reddit.com/r/haskell/comments/2zxekg/while_learning_haskell_i_m… "Unit tests are double entry bookkeeping" (EvanDaniel) https://www.reddit.com/r/haskell/comments/308ps6/what_are_your_most_persuas… augustss> "Well, type checking is worst case exponential…" barsoap> "Yep. That's also the reason why I don't really get the insistence of dependently-typed languages to have to be total at the type level: I don't care whether type-checking takes ten or infinitely many years, both figures are too large." https://www.reddit.com/r/haskell/comments/309430/where_does_ghc_spend_most_… "Our prophet Djistra said that a testing shows the presence, not the absence of bugs … <snip> … Today Djistra would have been stoned under a myriad of inutile unit tests that people perform for a sense of false security, in a sort of superstitious sacrificial ritual, a waste of time to convince himself and others that his software is right." (agocorona) https://www.reddit.com/r/haskell/comments/308ps6/what_are_your_most_persuas… "You might also consider these sorts of infelicities as teachable moments" (ericpashman) https://www.reddit.com/r/haskell/comments/2zxekg/while_learning_haskell_i_m… "Nice gradual progression there. Big O notion, smoothly divided into 3 easy parts, then bam, Coyoneda. =) I approve. [Yes, I realize it is a bag of topics, not a course outline, but it still grabbed me.]" (edwardkmett) https://www.reddit.com/r/haskell/comments/2zqyes/we_released_a_video_librar…

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Workshop on Type Inference and Automated Proving
by Frantisek Farka 18 May '15

18 May '15

********************************************************************* WORKSHOP ON TYPE INFERENCE AND AUTOMATED PROVING Tuesday the 12th of May, 12PM to 6PM School Of Computing, University of Dundee http://staff.computing.dundee.ac.uk/frantisekfarka/tiap/ ********************************************************************* Refreshments will be available from 12:00, with talks beginning at 12:45. For the detailed programme please see the above website. Talks: Tom Schrijvers (Katholieke Universiteit Leuven) GADTs Meet Their Match: Pattern-matching Warnings that Account for GADTs, Guards, and Laziness Bob Atkey (University of Strathclyde) An Algebraic Approach to Typechecking and Elaboration Edwin Brady (University of St Andrews) Implementing a Dependently Typed Programming Language Peng Fu (University if Dundee) Nontermination Analysis for Evidence Construction in Type Class Inference Adam Gundry (Well-Typed LLP) A Typechecker Plugin for Units of Measure: Domain-specific Constraint Solving in GHC Haskell Katya Komendantskaya (University of Dundee) Structural Resolution and Universal Productivity Checker J. Garrett Morris (University of Edinburgh) Substructural Types with Class After the talks we plan to continue the discussion at the nearby Duke's Corner bar and then go for dinner, place is yet to be announced but in the walking distance from both Seagate bus station and Dundee railway station. Please let us know if you are coming by either replying to this email, or by contacting me at ffarka(a)dundee.ac.uk If possible please indicate whether you wish to join us for dinner. With regards, František Farka

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all for Contributions - Haskell Communities and Activities Report, May 2015 edition (28th edition)
by Mihai Maruseac 13 May '15

13 May '15

Dear all, We would like to collect contributions for the 28th edition of the ============================================================ Haskell Communities & Activities Report http://www.haskell.org/haskellwiki/Haskell_Communities_and_Activities_Report Submission deadline: 17 May 2015 (please send your contributions to hcar at haskell.org, in plain text or LaTeX format) ============================================================ This is the short story (one extra point to the story added from previous editions): * If you are working on any project that is in some way related to Haskell, please write a short entry and submit it. Even if the project is very small or unfinished or you think it is not important enough --- please reconsider and submit an entry anyway! * If you are interested in an existing project related to Haskell that has not previously been mentioned in the HCAR, please tell us, so that we can contact the project leaders and ask them to submit an entry. * **NEW**: If you are working on a project that is looking for contributors, please write a short entry and submit it, mentioning that your are looking for contributors. The final report might have an index with such projects, provided we get enough such submissions. * Feel free to pass on this call for contributions to others that might be interested. More detailed information: The Haskell Communities & Activities Report is a bi-annual overview of the state of Haskell as well as Haskell-related projects over the last, and possibly the upcoming six months. If you have only recently been exposed to Haskell, it might be a good idea to browse the previous edition --- you will find interesting projects described as well as several starting points and links that may provide answers to many questions. Contributions will be collected until the submission deadline. They will then be compiled into a coherent report that is published online as soon as it is ready. As always, this is a great opportunity to update your webpages, make new releases, announce or even start new projects, or to talk about developments you want every Haskeller to know about! Looking forward to your contributions, Mihai Maruseac and Alejandro Serrano Mena FAQ: Q: What format should I write in? A: The required format is a LaTeX source file, adhering to the template that is available at: http://haskell.org/communities/05-2015/template.tex There is also a LaTeX style file at http://haskell.org/communities/05-2015/hcar.sty that you can use to preview your entry. If you do not know LaTeX, then use plain text. If you modify an old entry that you have written for an earlier edition of the report, you should soon receive your old entry as a template (provided we have your valid email address). Please modify that template, rather than using your own version of the old entry as a template. Q: Can I include Haskell code? A: Yes. Please use lhs2tex syntax (http://www.andres-loeh.de/lhs2tex/) The report is compiled in mode polycode.fmt. Q: Can I include images? A: Yes, you are even encouraged to do so. Please use .jpg or .png format, then, PNG being preferred for simplicity. Q: Should I send files in .zip archives or similar? A: No, plain file attachements are the way. Q: How much should I write? A: Authors are asked to limit entries to about one column of text. A general introduction is helpful. Apart from that, you should focus on recent or upcoming developments. Pointers to online content can be given for more comprehensive or "historic" overviews of a project. Images do not count towards the length limit, so you may want to use this opportunity to pep up entries. There is no minimum length of an entry! The report aims for being as complete as possible, so please consider writing an entry, even if it is only a few lines long. Q: Which topics are relevant? A: All topics which are related to Haskell in some way are relevant. We usually had reports from users of Haskell (private, academic, or commercial), from authors or contributors to projects related to Haskell, from people working on the Haskell language, libraries, on language extensions or variants. We also like reports about distributions of Haskell software, Haskell infrastructure, books and tutorials on Haskell. Reports on past and upcoming events related to Haskell are also relevant. Finally, there might be new topics we do not even think about. As a rule of thumb: if in doubt, then it probably is relevant and has a place in the HCAR. You can also simply ask us. Q: Is unfinished work relevant? Are ideas for projects relevant? A: Yes! You can use the HCAR to talk about projects you are currently working on. You can use it to look for other developers that might help you. You can use HCAR to ask for more contributors to your project, it is a good way to gain visibility and traction. Q: If I do not update my entry, but want to keep it in the report, what should I do? A: Tell us that there are no changes. The old entry will typically be reused in this case, but it might be dropped if it is older than a year, to give more room and more attention to projects that change a lot. Do not resend complete entries if you have not changed them. Q: Will I get confirmation if I send an entry? How do I know whether my email has even reached its destination, and not ended up in a spam folder? A: Prior to publication of the final report, we will send a draft to all contributors, for possible corrections. So if you do not hear from us within two weeks after the deadline, it is safer to send another mail and check whether your first one was received. -- Mihai Maruseac (MM) "If you don't know, the thing to do is not to get scared, but to learn." -- Atlas Shrugged.

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CFP: UNIF 2015
by Mateu Villaret 30 Apr '15

30 Apr '15

========================================================== Call for Papers UNIF 2015 The 29th International Workshop on Unification June 28, 2015. Warsaw, Poland http://rdp15.mimuw.edu.pl/index.php?site=unif ********* part of the Federated Conference on Rewriting, Deduction, and Programming (RDP'15) ========================================================== UNIF 2015 is the 29th event in a series of international meetings devoted to unification theory and its applications. Unification is concerned with the problem of identifying terms, finding solutions for equations, or making formulas equivalent. It is a fundamental process used in a number of fields of computer science, including automated reasoning, term rewriting, logic programming, natural language processing, program analysis, types, etc. The International Workshop on Unification (UNIF) is a yearly forum for researchers in unification theory and related fields to meet old and new colleagues, to present recent (even unfinished) work, and to discuss new ideas and trends. It is also a good opportunity for young researchers and scientists working in related areas to get an overview of the current state of the art in unification theory. Topics of Interest ------------------ A non-exhaustive list of topics of interest include: - Unification algorithms, calculi and implementations - Equational unification and unification modulo theories - Unification in modal, temporal and description logics - Admissibility of inference rules - Narrowing - Matching algorithms - Constraint solving - Combination problems - Disunification - Higher-Order unification - Type checking and reconstruction - Typed unification - Complexity issues - Query answering - Implementation techniques - Applications of unification - Antiunification/Generalization Submission ---------- Following the tradition of UNIF, we call for submissions of abstracts (5 pages) in EasyChair style, to be submitted electronically as PDF files through the EasyChair submission site: https://easychair.org/conferences/?conf=unif2015 Abstracts will be evaluated by the Programme Committee (if necessary with support from external reviewers) regarding their significance for the workshop. Accepted abstracts will be presented at the workshop and included in the informal proceedings of the workshop, available in printed form at the workshop and in electronic form from the UNIF homepage: http://www.pps.jussieu.fr/~treinen/unif/ Based on the number and quality of submissions we will decide whether to organize a special journal issue. Important Dates --------------- * Paper Submission: May 3, 2015 * Notification of Acceptance: May 31, 2015 * Final version: June 7, 2015 * Conference: June 28, 2015 Programme Committee ------------------- * Franz Baader, TU Dresden, Germany * Santiago Escobar, Universitat Politecnica de Valencia, Spain (co-chair) * Adria Gascon, SRI international, USA * Silvio Ghilardi, Universita di Milano, Italy * Artur Jez, MPI, Germany * Temur Kutsia, RISC, Johannes Kepler University Linz, Austria * Jordi Levy, IIIA-CSIC, Spain * Christopher Lynch, Clarkson University, USA * George Metcalfe, University of Bern, Switzerland * Paliath Narendran, University at Albany-SUNY, USA * Jan Otop, IST, Austria * Christophe Ringeissen, LORIA-INRIA Lorraine, France * Manfred Schmidt-Schauss, Goethe-University Frankfurt, Germany * Mateu Villaret, Universitat de Girona, Spain (co-chair) For more information, please contact any of the two chairs Santiago Escobar or Mateu Villaret.

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[haskell.org Google Summer of Code] 18 Projects Accepted
by Edward Kmett 28 Apr '15

28 Apr '15

I'd like to thank everyone for helping us to get the largest Google Summer of Code we've ever had for haskell.org off the ground! We have 18 accepted projects this year, spanning the entire ecosystem. You can find the official list on: https://www.google-melange.com/gsoc/org2/google/gsoc2015/haskell The most notable change this year is that in addition to the usual stable full of cabal tweaks (3 projects this year), and other infrastructure and library changes and the odd darcs project here and there (1 project), we also took it upon ourselves to act as an umbrella organization for purescript (2 projects). * I'd like to thank Johan Tibell for helping us get our ideas organized, and the /r/haskell moderators for leaving the brainstorming page "stickied" for the duration. It rather dramatically improved both the quantity and the quality of proposals we received. After I put out a call for additional mentoring help, we had 44 mentors step up to offer to help this time around, showing that we still have capacity to grow in years to come. Thank you all for putting in the time to help rank proposals and for your continued efforts over this summer. I'd also like to thank Shachaf Ben-Kiki and Gershom Bazerman for helping out with the administration side of things. Now we are entering what Google calls the "Community Bonding" period. Students officially start coding May 25th. Please feel free to reach out to me if you have any questions or concerns. -Edward Kmett haskell.org Google Summer of Code Administrator * Purescript and Darcs proposals went into the same pool as everyone else this year without earmarking.

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MPC 2015 - Call For Participation
by Maciej Pirog 27 Apr '15

27 Apr '15

CALL FOR PARTICIPATION 12th International Conference on Mathematics of Program Construction (MPC 2015) Königswinter, Germany, 29 June - 1 July 2015 http://www.cs.ox.ac.uk/conferences/MPC2015/ Early registration deadline: *** 29 May 2015 *** Hotel rooms reserved until: *** 29 May 2015 *** BACKGROUND The MPC conferences aim to promote the development of mathematical principles and techniques that are demonstrably practical and effective in the process of constructing computer programs, broadly interpreted. VENUE The conference will take place in Königswinter, Maritim Hotel, where accommodation has been reserved. Königswinter is situated on the right bank of the river Rhine, opposite Germany's former capital Bonn, at the foot of the Siebengebirge. REGISTRATION To register for the conference send an email to mpc2015(a)online.de stating your name and affiliation. We will then provide further details, including hotel booking. You can also use the email address for any queries you might have. The early registration fee for the conference is 375 Euros if you pay via bank transfer and 385 Euros if you pay using PayPal. The early registration deadline is 29 May 2015; after this point, the registration fee rises to 425 Euros (bank transfer) and 435 Euros (PayPal). We have a block booking of rooms at the conference hotel at a special reduced rate, but only until 29th May 2015; after this point, the rooms will be released and the special rate unavailable. INVITED SPEAKERS * Carroll Morgan, University of New South Wales (Link http://www.cse.unsw.edu.au/~carrollm/) "A nondeterministic lattice of information" * Torsten Grust, Universität Tübingen (Link http://db.inf.uni-tuebingen.de/team/TorstenGrust.html) "A Compilation of Compliments for a Compelling Companion: the Comprehension" ACCEPTED PAPERS * "Exploring an Interface Model for CKA" Bernhard Möller and Tony Hoare * "On Rely-Guarantee Reasoning" Stephan Van Staden * "A Relation-Algebraic Approach to Multirelations and Predicate Transformers" Rudolf Berghammer and Walter Guttmann * "Preference Decomposition and the Expressiveness of Preference Query Languages" Patrick Roocks * "Hierarchy in Generic Programming Libraries" José Pedro Magalhães and Andres Löh * "Polynomial Functors Constrained by Regular Expressions" Dan Piponi and Brent Yorgey * "A Program Construction and Verification Tool for Separation Logic" Brijesh Dongol, Victor B. F. Gomes, and Georg Struth * "Calculating Certified Compilers for Non-Deterministic Languages" Patrick Bahr * "Notions of Bidirectional Computation and Entangled State Monads" Faris Abou-Saleh, James Cheney, Jeremy Gibbons, James McKinna, and Perdita Stevens * "A clear picture of lens laws" Sebastian Fischer, Zhenjiang Hu, and Hugo Pacheco * "Regular Varieties of Automata and Coequations" Julian Salamanca, Jan Rutten, Marcello Bonsangue, Enric Cosme-Llópez, and Adolfo Ballester-Bolinches * "Column-wise Extendible Vector Expressions and the Relational Computation of Sets of Sets" Rudolf Berghammer * "Turing-Completeness Totally Free" Conor McBride * "Auto in Agda: Programming proof search using reflection" Pepijn Kokke and Wouter Swierstra * "Fusion for Free: Efficient Algebraic Effect Handlers" Nicolas Wu and Tom Schrijvers PROGRAMME COMMITTEE Ralf Hinze University of Oxford, UK (chair) Eerke Boiten University of Kent, UK Jules Desharnais Université Laval, Canada Lindsay Groves Victoria University of Wellington, New Zealand Zhenjiang Hu National Institute of Informatics, Japan Graham Hutton University of Nottingham, UK Johan Jeuring Utrecht University and Open University, The Netherlands Jay McCarthy Vassar College, US Bernhard Möller Universität Augsburg, Germany Shin-Cheng Mu Academia Sinica, Taiwan Dave Naumann Stevens Institute of Technology, US Pablo Nogueira Universidad Politécnica de Madrid, Spain Ulf Norell University of Gothenburg, Sweden Bruno C. d. S. Oliveira The University of Hong Kong, Hong Kong José Nuno Oliveira Universidade do Minho, Portugal Alberto Pardo Universidad de la República, Uruguay Christine Paulin-Mohring INRIA-Université Paris-Sud, France Tom Schrijvers KU Leuven, Belgium Emil Sekerinski McMaster University, Canada Tim Sheard Portland State University, US Anya Tafliovich University of Toronto Scarborough, Canada Tarmo Uustalu Institute of Cybernetics, Estonia Janis Voigtländer Universität Bonn, Germany LOCAL ORGANIZERS Ralf Hinze University of Oxford, UK (co-chair) Janis Voigtländer Universität Bonn, Germany (co-chair) José Pedro Magalhães Standard Chartered Bank, UK Maciej Piróg University of Oxford, UK Nicolas Wu University of Bristol, UK For queries about local matters, please write to jv(a)informatik.uni-bonn.de.

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ANN: New Haskell.org Committee Members
by Gershom B 27 Apr '15

27 Apr '15

Following the self-nomination period and discussion, the Haskell.org committee has selected new members: * Edward Kmett (reappointment) * Ryan Trinkle * John Wiegley As per the rules of the committee, this discussion was held among the current members of the committee, and the outgoing members of the committee who were not seeking reappointment. Thank you to all candidates who submitted a self-nomination. All of the nominations we received were very strong, and we would encourage all those who nominated themselves to consider self-nominating again in the future. We would also like to thank our two outgoing members, Jason Dagit and Brent Yorgey, for their service. Cheers, Gershom

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