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Kyiv Haskell Learning Group Meetups
by Kostiantyn Rybnikov 09 Oct '17

09 Oct '17

Hi! We're starting a Haskell Learning Group in Kyiv, Ukraine. First Meetup will be at 17 October (Tuesday) and will continue on weekly basis at the Institute of Mathematics. See full info about the first meetup at https://www.meetup.com/Kyiv-Haskell-Learning-Group/events/243945548/ Info about the course itself (in Ukrainian): https://github.com/KyivHaskell/haskell-study-startup See you there!

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ANN: hmep -- genetic multi expression programming package
by masterdeZign 09 Oct '17

09 Oct '17

Dear Haskell community, I am delighted to contribute a new package for the first time. Today, I am happy to announce `hmep` http://hackage.haskell.org/package/hmep/ bringing Multi Expression Programming to Haskell. Multi Expression Programming is a genetic programming variant encoding multiple solutions in the same chromosome. A chromosome is a computer program. Each gene is featuring code reuse. The latest version is of course on GitHub https://github.com/masterdezign/hmep Thank you for your kind attention, Happy Monday, Bogdan Penkovsky

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Journal of Functional Programming - Call for PhD Abstracts
by Graham Hutton 09 Oct '17

09 Oct '17

Dear all, If you or one of your students recently completed a PhD in the area of functional programming, please submit the dissertation abstract for publication in JFP: simple process, no refereeing, open access, deadline 31st October 2017. Please share! Best wishes, Graham ============================================================ CALL FOR PHD ABSTRACTS Journal of Functional Programming Deadline: 31st October 2017 http://tinyurl.com/jfp-phd-abstracts ============================================================ PREAMBLE: Many students complete PhDs in functional programming each year. As a service to the community, the Journal of Functional Programming publishes the abstracts from PhD dissertations completed during the previous year. The abstracts are made freely available on the JFP website, i.e. not behind any paywall. They do not require any transfer of copyright, merely a license from the author. A dissertation is eligible for inclusion if parts of it have or could have appeared in JFP, that is, if it is in the general area of functional programming. The abstracts are not reviewed. Please submit dissertation abstracts according to the instructions below. We welcome submissions from both the PhD student and PhD advisor/supervisor although we encourage them to coordinate. ============================================================ SUBMISSION: Please submit the following information to Graham Hutton <graham.hutton(a)nottingham.ac.uk> by 31st October 2017. o Dissertation title: (including any subtitle) o Student: (full name) o Awarding institution: (full name and country) o Date of PhD award: (month and year; depending on the institution, this may be the date of the viva, corrections being approved, graduation ceremony, or otherwise) o Advisor/supervisor: (full names) o Dissertation URL: (please provide a permanently accessible link to the dissertation if you have one, such as to an institutional repository or other public archive; links to personal web pages should be considered a last resort) o Dissertation abstract: (plain text, maximum 1000 words; you may use \emph{...} for emphasis, but we prefer no other markup or formatting in the abstract, but do get in touch if this causes significant problems) Please do not submit a copy of the dissertation itself, as this is not required. JFP reserves the right to decline to publish abstracts that are not deemed appropriate. ============================================================ PHD ABSTRACT EDITOR: Graham Hutton School of Computer Science University of Nottingham Nottingham NG8 1BB United Kingdom ============================================================ This message and any attachment are intended solely for the addressee and may contain confidential information. If you have received this message in error, please send it back to me, and immediately delete it. Please do not use, copy or disclose the information contained in this message or in any attachment. Any views or opinions expressed by the author of this email do not necessarily reflect the views of the University of Nottingham. This message has been checked for viruses but the contents of an attachment may still contain software viruses which could damage your computer system, you are advised to perform your own checks. Email communications with the University of Nottingham may be monitored as permitted by UK legislation.

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Deprecating STM invariant mechanism
by Ben Gamari 09 Oct '17

09 Oct '17

tl;dr. Do you use Control.Monad.STM.always? If so say so on this [1] proposal otherwise the interface may be removed. Hello everyone, GHC's STM subsystem has long had the ability to run user-specified invariant checks when committing transactions, embodied by the Control.Monad.STM.always and alwaysSucceeds functions. However, if Hackage is any indication this feature has seen very little use of the past ten years. In fact, it has very likely been quite broken (#14310) for this entire duration. Consequently, I suggest that we begin deprecating the mechanism. See the deprecation Proposal [1] for full details. Please leave a comment if you object. Cheers, - Ben [1] https://github.com/ghc-proposals/ghc-proposals/pull/77

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CoqPL 2018: Call for Presentations
by Sergey, Ilya 06 Oct '17

06 Oct '17

==================================================================== CoqPL 2018 Coq for Programming Languages -- A Coq users and developers meeting 13 January 2018, co-located with POPL (as usual) Los Angeles, California, United States CALL FOR PRESENTATIONS https://popl18.sigplan.org/track/CoqPL-2018 ==================================================================== Workshop Overview ----------------- The series of CoqPL workshops provide an opportunity for programming languages researchers to meet and interact with one another and members from the core Coq development team. At the meeting, we will discuss upcoming new features, see talks and demonstrations of exciting current projects, solicit feedback for potential future changes, and generally work to strengthen the vibrant community around our favourite proof assistant. Topics in scope include but are no limited to: * General purpose libraries and tactic language extensions; * Domain-specific libraries for programming language formalization and verification; * IDEs, profilers, tracers, debuggers, and testing tools; * Reports on ongoing proof efforts conducted via (or in the context of) the Coq proof assistant; * Experience reports from Coq usage in educational or industrial contexts. To foster open discussion of cutting edge research which can later be published in full conference proceedings, we will not publish papers from the workshop. Workshop Format --------------- The workshop format will be driven by members of the Coq community. We will solicit abstracts for talks and proposals for demonstrations and flesh out format details based on responses. We expect the final program to include experiment reports, panel discussions, and invited talks. Talks will be selected according to relevance to the workshop, based on the submission of an extended abstract. Submission Details ------------------ * Abstract Submission : Monday, October, 16th, 2017 * Author Notification : Monday, November 6th, 2017 * Workshop : Saturday, January 13th, 2018 Submissions should be extended abstracts of 1-2 pages in portable document format (PDF). Submission is via EasyChair: https://easychair.org/conferences/?conf=coqpl2018 Program Committee ----------------- * Yves Bertot, INRIA (Workshop Co-chair) * Ilya Sergey, University College London (Workshop Co-chair) * Andrew Appel, Princeton University * Benjamin Delaware, Purdue University * Xinyu Feng, University of Science and Technology of China * Hugo Herbelin, INRIA * Chantal Keller, Université Paris-Sud * Ekaterina Komendantskaya, Heriot-Watt University * Beta Ziliani, Universidad Nacional de Córdoba Contact ----------------- For any queries, please contact : coqpl2018 at easychair.org<http://easychair.org>

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claiming maintainer position of a HackageDB package
by Guillaume Hoffmann 06 Oct '17

06 Oct '17

Hi, I would like to submit a new version of the following package: https://hackage.haskell.org/package/mime-string Unfortunately, I only received private consent from the current maintainer that I would become the maintainer of this package, more than one month ago. Since then I had not received any answer to my request and I cannot upload a new version to HackageDB. Is there a procedure I could summon to become the maintainer of this package on HackageDB? Thanks Guillaume PS: for the anecdote, darcsden needs this new version of mime-string.

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claiming maintainership of bsd-sysctl package
by info＠maximka.de 06 Oct '17

06 Oct '17

I'm still interested to take over the package. Regards, Alexei > ---------- Original Message ---------- > From: Alexei Pastuchov <info(a)maximka.de> > To: admin(a)hackage.haskell.org > Cc: mhenrion(a)gmail.com, info(a)maximka.de > Date: 31 January 2017 at 22:04 > Subject: bsd-sysctl 1.0.7 > > Hi, > the installation of bsd-sysctl v1.0.7 ends in exception: > Not in scope: `catch' > > I created a pull request for the bug at the end of 2015 and short time later the author/maintainer asked me if I'm interested in taking over the maintainership. > > As described in https://wiki.haskell.org/Taking_over_a_package I asked him to add my hackage account 'palik' to the maintainer group in my last message a couple of months ago and I'm going to ask you for the maintainer permissions. > > Here the aforementioned pull request https://bitbucket.org/mux/bsd-sysctl/pull-requests/ > > Best regards, > Alexei

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[Call for Contributions] Haskell Communities and Activities Report, November 2017 edition (33rd edition)
by Mihai Maruseac 06 Oct '17

06 Oct '17

Dear all, We would like to collect contributions for the 33rd edition of the ============================================================ Haskell Communities & Activities Report http://www.haskell.org/haskellwiki/Haskell_Communities_and_Activities_Report Submission deadline: 5 November 2017 (please send your contributions to hcar at haskell.org, in plain text or LaTeX format, both are equally accepted) ============================================================ This is the short story: * 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. * 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. * 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 FAQ: Q: What format should I write in? A: The usual format is a LaTeX source file, adhering to the template that is available at: http://haskell.org/communities/11-2017/template.tex There is also a LaTeX style file at http://haskell.org/communities/11-2017/hcar.sty that you can use to preview your entry. If you do not know LaTeX or don't want to use it or don't have time to translate your entry into it, then please use plain text, it is better to have an entry in plain-text which we will translate than not have it at all. 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 is preferred for simplicity. Q: Should I send files in .zip archives or similar? A: No, plain file attachments 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 can't solve a problem, then there's an easier problem you can solve: find it." -- George Polya

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Determine instance method from class method callsite
by Robin Palotai 06 Oct '17

06 Oct '17

Sorry, I messed up subject and mailing list. Copying to both list now after the mistake (wanted only ghc-devs for specificity). Thanks! 2017-09-19 7:36 GMT+02:00 Robin Palotai <palotai.robin(a)gmail.com>: > Hello GHC devs, > > Before inventing the wheel, want to check if there is a GHC API way to > look up the (fully) resolved instance method from a class method. > > For example, given a code > > data Foo Int deriving Show > > bar = show (Foo 3) > > when inspecting the Typechecked AST for bar's show call, I would like to > get to the Name / Id of 'show' of the 'Show' typeclass. > > I believe I could use splitHsSigmaTy on the HsType of the function call to > get the context, and then evaluate the HsWrapper somehow to find out what > instance dictionary is applied to the class restriction in the context, and > then look up the instance method from the dictionary.. > > Two questions: > > 1) Is there maybe functionality for this? > > 2) If not, is there any guarantee about the constraint order in the > context, at the method call? So I could more easily determine which > constraint's application to look for.. > > Any hints welcome && Thank you! > Robin >

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Cabal hell (8.2.1,/Haskell Package/MacOS X)
by Stuart A. Kurtz 06 Oct '17

06 Oct '17

Dear Cafe, I've had my first extended visit into cabal hell... ghc: 8.2.1 (Haskell Platform) cabal: 2.0.0.2 cabal-install: 2.0.0.0 OS: MacOS X 10.13 (High Sierra) I have problems around trying to install some standard packages: hlint, aeson. A typical error reported by cabal is <command line>: cannot satisfy -package-id hashable-1.2.6.1-14fEJP30YhAG9w115PODz0: hashable-1.2.6.1-14fEJP30YhAG9w115PODz0 is unusable due to shadowed dependencies: text-1.2.2.2-EGUst8sqNAZCw1xLPcmcMH FWIW, the versions of these packages reported by ghc-pkg are hashable-1.2.6.1 text-1.2.2.2 Suggestions welcome... Peace, Stu

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