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Call for maintainer: formatting package
by Christopher Done 03 Nov '19

03 Nov '19

Hi all, The formatting package needs a maintainer. I made this package 6 years ago based on the HoleyMonoid package's idea. I thought it would become a staple package for me. Since then, I have basically never actually used it in a project. It turns out, I don't like the printf-style of doing printing at all, and prefer to just manually append things. As such, it doesn't make sense for me to maintain this package. Feel free to comment here or on the GitHub issue if you are interested: https://github.com/chrisdone/formatting/issues/58 Cheers, Chris

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Expired certificate for prime.haskell.org
by Simon Jakobi 02 Nov '19

02 Nov '19

Hi! I just wanted to give someone a link to the Semigroup-Monoid-proposal, but couldn't open the page in Chromium: https://prime.haskell.org/wiki/Libraries/Proposals/SemigroupMonoid There's already a short email thread regarding the issue from April on the haskell-prime mailing list: https://mail.haskell.org/pipermail/haskell-prime/2019-April/004448.html It would be nice if proposals like the SMP remained accessible! Cheers, Simon

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How to build a horse with Haskell (comic extension)
by J Ho 31 Oct '19

31 Oct '19

There was this comics “how to build a horse” with different languages. I’ve always felt Haskell was missing. Found this on Quora - https://www.quora.com/How-do-you-build-a-horse-with-the-Haskell-programming… How to build a horse with Haskell. Building just a horse is boring, so you generalize it to a spherical horse in vacuum that can represent other animals sufficiently well. It takes 5 years, 43 research papers and only 3 people in the world can ride it (including SPJ). You build a horse. It’s fast, but lazy. You build a beautiful, friendly horse. You call it Monadic Quadro-pedo-functorial Transporter. People are afraid to touch it and it dies of loneliness. You build something that is Maybe a horse. All your horses come in boxes with bottom. You were a java programmer so you build a horse factory. It gives you Either a horse or a terrible runtime abomination. You build an existential horse. You can’t see or access its hoofs, tail, back, anything. It just sort of sits there and stares at you. You build an infinitely large horse. You can still ride it, because it’s lazy (it just sits there, just like the existential, and you crawl on its back slowly). You tease Java programmers who can’t possibly ride infinite horses. You build an even faster horse that is unboxed. You notice it is eager. You build a higher-kinded Horsificator. It turns anything else into horses. data Horsificator a = Horse a | Abomination You want to ride a rhino, but they normally would kill you. You build a horse typeclass. You make rhinos an instance of Horse. Polymorphic domestication!

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Call for Workshop Proposals: ICFP 2020
by Sam Tobin-Hochstadt 30 Oct '19

30 Oct '19

CALL FOR WORKSHOP AND CO-LOCATED EVENT PROPOSALS ICFP 2020 25th ACM SIGPLAN International Conference on Functional Programming August 23 - 28, 2020 Jersey City, NJ, US https://icfp19.sigplan.org/ The 25th ACM SIGPLAN International Conference on Functional Programming will be held in Jersey City, New Jersey on August 23-28, 2020. 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 symposiums) to be affiliated with ICFP 2020 and sponsored by SIGPLAN. These events should be less formal and more 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 August 23rd (the day before ICFP) and 27-28th of August (the two days after ICFP). ---------------------------------------------------------------------- Submission details Deadline for submission: November 15, 2019 Notification of acceptance: December 13, 2019 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 2020 workshop co-chairs (Jennifer Hackett and Leonidas Lampropoulos) via email to icfp-workshops-2020(a)googlegroups.com by November 15, 2019. (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 13, 2019, 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/icfp2020-files/icfp20-workshops-form.txt Further information about SIGPLAN sponsorship is available at: http://www.sigplan.org/Resources/Proposals/Sponsored/ ---------------------------------------------------------------------- Selection committee The proposals will be evaluated by a committee comprising the following members of the ICFP 2020 organizing committee, together with the members of the SIGPLAN executive committee. Workshop Co-Chair: Jennifer Hackett (University of Nottingham) Workshop Co-Chair: Leonidas Lampropoulos (University of Maryland) General Chair: Stephanie Weirich (University of Pennsylvania) Program Chair: Adam Chlipala (MIT) ---------------------------------------------------------------------- Further information Any queries should be addressed to the workshop co-chairs (Jennifer Hackett and Leonidas Lampropoulos), via email to icfp-workshops-2020(a)googlegroups.com.

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A Haskell meetup in San Francisco today
by Dimitri DeFigueiredo 29 Oct '19

29 Oct '19

After a long wait, there's a haskell meetup in San Francisco today. https://www.meetup.com/Bay-Area-Haskell-Users-Group/events/265110367/ Exciting! :-) Dimitri -- 2E45 D376 A744 C671 5100 A261 210B 8461 0FB0 CA1F

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ANN: reflex-basic-host-0.2.0.1, reflex-backend-socket-0.2.0.0
by Jack Kelly 29 Oct '19

29 Oct '19

I have just pushed two packages to hackage: 1. reflex-basic-host-0.2.0.1[1], a reflex host library for backend work, and 2. reflex-backend-socket-0.2.0.0[2] a reflex-flavoured wrapper around TCP sockets. The most important changes to reflex-basic-host are: * Hosts no longer needlessly fork a thread, meaning that it is safe to call native code which expects all library calls to come from a common thread; and * Each host runs in a separate Reflex timeline, which makes it possible to run multiple Reflex hosts in parallel. There is an example[3] on GitHub demonstrating two hosts passing messages to each other. I hope people find it useful. GitHub issues and PRs welcome[4, 5]. Best, -- Jack [1] https://hackage.haskell.org/package/reflex-basic-host-0.2.0.1 [2] https://hackage.haskell.org/package/reflex-backend-socket-0.2.0.0 [3] https://github.com/qfpl/reflex-basic-host/blob/master/example/Multithread.hs [4] https://github.com/qfpl/reflex-basic-host [5] https://github.com/qfpl/reflex-backend-socket

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Functional Conference 2019 with Edward Kmett keynote | Bengaluru, 13-17 November
by John Sinclair 29 Oct '19

29 Oct '19

Hi haskell-cafe! If you're in India, you'll be interested in Functional Conference 2019. It's an opportunity to meet up with other functional programmers and Haskell users. You'll learn from Edward Kmett who is chairman of the Haskell Core Libraries Committee. He'll be delivering a keynote, a workshop and more. https://confng.in/Kmg8m-Tx Michael Snoyman from Israel will be giving an Applied Haskell workshop. https://confng.in/24haPWyw All up their are 15 sessions covering Haskell to broaden your horizons and deepen your knowledge. Functional Conf is the premiere event for Functional programmers in India. Our goal is to support the community with access to high quality speakers, who are innovating in this field. Learn more about the conference here: https://confng.in/wAQ41Z4q To get 10% off when you register, use the code: FnConf19Dis$ https://twitter.com/FnConf <https://llink.to/?u=https:%2F%2Ftwitter.com%2FFnConf&e=df52b49527f43fa29bda…> https://www.linkedin.com/showcase/functional-conf <https://llink.to/?u=https:%2F%2Fwww.linkedin.com%2Fshowcase%2Ffunctional-co…>

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reading from a unix pipe and then from the user
by Aramís Concepción Durán 28 Oct '19

28 Oct '19

Hello, I'm trying to write a program that first reads input from a pipe and then reads keyboard input from the user (like fzf, the fuzzy finder). Under different circumstances I could open a handle to `/dev/tty` and use the `hGet...` functions from `System.IO` to get the user's keyboard input, but I'm constructing the text user interface with the brick library, which doesn't seem to give my any way to sneak in alternative handles through its application entry point functions. So, what I'm looking for is a function which takes an `IO ()` function like the usual `main` and a `Handle` and turns it into an `IO ()` function that reads from the provided handle instead of `stdin`. Does that make sense? I might be looking for something that doesn't exist. Or I'm lacking the language to get results from a search engine. To illustrate the problem further, here is a condensed brick application: import qualified Brick.Main as Main import qualified Brick.Types as Types import qualified Graphics.Vty as Vty import Brick.AttrMap ( attrMap ) import Brick.Widgets.Core ( str ) type Event = Types.EventM () ( Types.Next () ) main = let app = Main.App { Main.appChooseCursor = Main.neverShowCursor , Main.appHandleEvent = \ _ _ -> Main.halt () :: Event , Main.appStartEvent = pure , Main.appAttrMap = \ _ -> attrMap Vty.currentAttr [] , Main.appDraw = \ _ -> [ str Hit any key to exit. ] } in Main.defaultMain app () How do I get this `main` function to read from a custom handle intead of stdin?

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Munich Haskell Meeting, 2019-10-29 @ 19:30
by Leah Neukirchen 27 Oct '19

27 Oct '19

Dear all, Next week, our monthly Munich Haskell Meeting will take place again on Tuesday, October 29 at Augustiner-Gaststätte Rumpler at 19h30. For details see here: http://muenchen.haskell.bayern/dates.html If you plan to join, please add yourself to this dudle so we can reserve enough seats! It is OK to add yourself to the dudle anonymously or pseudonymously. https://dudle.inf.tu-dresden.de/haskell-munich-oct-2019/ Everybody is welcome! cu, -- Leah Neukirchen <leah(a)vuxu.org> https://leahneukirchen.org/

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2nd Call for Contributions: BOB 2020 [Feb 28, Deadline Nov 8]
by Stefan Wehr 24 Oct '19

24 Oct '19

BOB Conference 2020 "What happens when we use what's best for a change?" http://bobkonf.de/2020/cfc.html Berlin, February 28 Call for Contributions Deadline: November 8, 2019 You are actively engaged in advanced software engineering methods, implement ambitious architectures and are open to cutting-edge innovation? Attend this conference, meet people that share your goals, and get to know the best software tools and technologies available today. We strive to offer a day full of new experiences and impressions that you can use to immediately improve your daily life as a software developer. If you share our vision and want to contribute, submit a proposal for a talk or tutorial! NOTE: The conference fee will be waived for presenters. Travel expenses will not be covered (for exceptions see "Speaker Grants"). Speaker Grants -------------- BOB has Speaker Grants available to support speakers from groups under-represented in technology. We specifically seek women speakers and speakers who are not be able to attend the conference for financial reasons. Shepherding ----------- The program committee offers shepherding to all speakers. Shepherding provides speakers assistance with preparing their sessions, as well as a review of the talk slides. Topics ------ We are looking for talks about best-of-breed software technology, e.g.: - functional programming - persistent data structures and database - event-based modelling and architectures - types - formal methods for correctness and robustness - abstractions for concurrency and parallelism - metaprogramming - probabilistic programming - math and programming - controlled side effects - beyond REST and SOAP - effective abstractions for data analytics - ... everything really that isn’t mainstream, but you think should be. Presenters should provide the audience with information that is practically useful for software developers. We're especially interested in experience reports. Other topics are also relevant, e.g.: - introductory talks on technical background - overviews of a given field - demos and how-tos Requirements ------------- We accept proposals for presentations of 45 minutes (40 minutes talk + 5 minutes questions), as well as 90 minute tutorials for beginners. The language of presentation should be either English or German. Your proposal should include (in your presentation language of choice): - An abstract of max. 1500 characters. - A short bio/cv - Contact information (including at least email address) - A list of 3-5 concrete ideas of how your work can be applied in a developer's daily life - additional material (websites, blogs, slides, videos of past presentations, …) Submit here: https://bobcfc.active-group.de/en/bob2020/cfp Organisation ------------ - Direct questions to contact at bobkonf dot de - Proposal deadline: November 8, 2019 - Notification: November 22, 2019 - Program: December 6, 2019 Program Committee ----------------- (more information here: https://bobkonf.de/2020/programmkomitee.html) - Matthias Fischmann, Wire - Matthias Neubauer, SICK AG - Nicole Rauch, Softwareentwicklung und Entwicklungscoaching - Michael Sperber, Active Group - Stefan Wehr, factis research Scientific Advisory Board - Annette Bieniusa, TU Kaiserslautern - Torsten Grust, Uni Tübingen - Peter Thiemann, Uni Freiburg

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