May 2016 - Haskell-Cafe

Announce: Haskell Platform 8.0.1
by Gershom B 28 May '16

28 May '16

On behalf of the Haskell Platform team, I'm happy to announce the release of Haskell Platform 8.0.1 Now available at https://www.haskell.org/platform/ This platform includes features initially planned in the "Improving the 'Get Haskell Experience'" proposal of June 2015. [1] * Minimal as well as Full distributions. The minimal distribution only includes GHC core libraries as well as additional tools. This is now the recommended distribution. The Full distribution remains an option for those who want a one-step installer with the broader set of platform libraries preinstalled. * Inclusion of the Stack tool for developing Haskell projects [2] Other highlights of this release include the following * The new cabal 1.24 including the great "new-build" tech preview of nix-like build dependency management [3] * On windows, a cabal/msys setup that allows packages such as "network" to build "out of the box". (almost*) * At long last, prebuilt Linux 32 bit platform installers Changes to Contents: * Some packages have been removed from the installed packages set (both minimal and full) including old-locale, old-time, cgi, and the transitive cgi dependencies: transformers-compat, multipart, and exceptions. * fixed has been added to the platform as a transitive dependency of GLUT. A full list of contents is available at https://www.haskell.org/platform/contents.html Thanks to all the contributors to this release, thanks to all the package and tool maintainers and authors, and a big thanks to the GHC team for putting together such an exciting new compiler release! A fuller list of new GHC changes is available at: https://mail.haskell.org/pipermail/ghc-devs/2016-May/012098.html A fuller list of new cabal changes is available at: http://coldwa.st/e/blog/2016-05-04-Cabal-1-24.html Happy Haskell Hacking all, Gershom [1] http://projects.haskell.org/pipermail/haskell-platform/2015-July/003129.html [2] http://haskellstack.org [3] http://blog.ezyang.com/2016/05/announcing-cabal-new-build-nix-style-local-b… * To build "network" and other msys-dependent packages on windows, you will need to augment your cabal config file with the following lines: extra-prog-path: C:\Program Files\Haskell Platform\8.0.1\msys\usr\bin extra-lib-dirs: C:\Program Files\Haskell Platform\8.0.1\mingw\lib extra-include-dirs: C:\Program Files\Haskell Platform\8.0.1\mingw\include

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Munich Haskell Meeting, 2016-05-30 @ 19:30 Max Emanuel Brauerei
by Christian Neukirchen 27 May '16

27 May '16

Dear all, Next week, our monthly Munich Haskell Meeting will take place again on Monday, May 30 at *Max Emanuel Brauerei* at 19h30. For details see here: http://chneukirchen.github.io/haskell-munich.de/dates.html **Please note the changed location!** If you plan to join, please add yourself *quickly* 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-may-2016/ Everybody is welcome! cu, -- Christian Neukirchen <chneukirchen(a)gmail.com> http://chneukirchen.org

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Hackage (partially) down?
by Bardur Arantsson 27 May '16

27 May '16

Hi all, I'm getting Error 503 Connection timed out Connection timed out Guru Mediation: Details: cache-ams4123-AMS 1464323906 827600523 Varnish cache server when trying to browse Hackage this morning. Anyone else having the same problem? (downforeveryoneorjustme.com says that "it's just me", so I'm guessing this is some sort of CDN issue?) Regards,

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Re: [Haskell-cafe] Haskell newb trying to write a basic program.
by Erik Rantapaa 26 May '16

26 May '16

Have a look at the HaskellForMaths package. Using the Math.Algebra.Group.PermutationGroup module the expression `elts (_A n)` will return all the permutations of A_n. On Thursday, May 26, 2016 at 6:39:52 PM UTC-5, Blake Sims wrote: > > Hi, > > I am a newb to Haskell and programming in general, but I was trying to > write a basic program to find the elements for the alternating group for > any n. > > For the symmetric group I wrote something like this > > input Data.List > > symmetric n = permutations ([1..n]) > > What if I just want to find the even permutations? What is the quick and > dirty way of doing this? I was looking at the package Data.Matrix and > messing around with permutation matrices, but there has got to be a quicker > and easier way of doing it. I am skimming the book learn you a Haskell, but > my attention span is pretty short so if someone could direct me in the > right direction I'd be much obliged. >

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GHC 8.0.1 Compile time regression + Trac ticket privileges
by aditya siram 26 May '16

26 May '16

[x-post from Reddit reply] Thanks so much for all the hard work! Unfortunately I have a compile time performance regression to report on my FLTKHS <https://github.com/deech/fltkhs> library. I also don't have a minimal example. There is a demo that took about 15 seconds compile and link in 7.10.3, but with no changes now takes over a minute in 8.0.1. I've reproduced this across machines and operating systems. Since there was interest expressed in using this example as a benchmark if any GHC devs are still willing to help, I'm willing to walk them through getting the library set up etc. It's not a long process. The tip of my Github branch has been updated to build with GHC 8.0.1. I made myself a Trac account but apparently I don't have Ticket privileges so it won't let me create one. My username is 'deech'. Thanks! -deech

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A Java bytecode interpreter written in Haskell
by Erik Dominikus 26 May '16

26 May '16

(Please keep expectations low for now; this is just a weekend project.) I have written, in Haskell, something that aspires to be a Java Virtual Machine (but I don't call it a JVM yet as it doesn't fully comply with the spec). The code is available here: https://github.com/edom/haji This is similar to Frege [3], but while Frege aims to run a variant of Haskell on Java, this project tries the other direction: running a subset of Java on Haskell. Thanks. Best, Erik Some related stuffs: [1] https://github.com/MateVM/MateVM [2] https://hackage.haskell.org/package/hs-java [3] https://github.com/Frege/frege [4] https://wiki.haskell.org/GHC:FAQ#Why_isn.27t_GHC_available_for_.NET_or_on_t… [5] https://github.com/levans/Open-Quark

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Interacting with Java in GHCVM
by Rahul Muttineni 25 May '16

25 May '16

Hi Haskell-Cafe, I've been working on a JVM backend for GHC [1] and I took some time to flesh out a design for the Java FFI [2] which will pretty much decide whether the project will be useful or not. I would love feedback from the community on how to improve the design or requests for important interop features that I have neglected. Thanks, Rahul Muttineni [1] http://github.com/rahulmutt/ghcvm [2] https://gist.github.com/rahulmutt/355505bce57c7c2cffd7d4cf5edddad4

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Example of FunBind without wrapping AbsBind?
by Robin Palotai 25 May '16

25 May '16

I was playing with the AST's typechecked tree, and found some examples of the subject, but can't tell what is the rule for that to occur. It was a local binding. Do you have a hint and/or a minimal example? Thanks! Robin

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ANN: new #haskell-atom channel, Atom setup doc
by Simon Michael 24 May '16

24 May '16

Hi all, Recently I helped a newcomer set up Haskell and Atom (the text editor/IDE - not the embedded systems DSL), and also for the first time succeeded in getting a "modern IDE experience" working with my own projects. I've saved my notes so far - I hope you'll also find them useful: https://github.com/simonmichael/haskell-atom-setup In the process I found some issues, looked for help in many places, and wished the #haskell-atom IRC channel existed. So I've started it: #haskell-atom on Freenode I'm an Emacs man, but I try all the available Haskell IDEs periodically. Atom is the first one where I've succeeded in getting inline error reporting working, and it's the only one I could recommend to a new programmer or a mainstream IDE lover right now. So I think this channel is worth having, and will grow. All welcome! Best, -Simon

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1st CfP: IFL 2016 (28th Symposium on Implementation and Application of Functional Languages)
by publicityifl＠gmail.com 24 May '16

24 May '16

Hello, Please, find below the first call for papers for IFL 2016. Please forward these to anyone you think may be interested. Apologies for any duplicates you may receive. best regards, Jurriaan Hage Publicity Chair of IFL --- IFL 2016 - Call for papers 28th SYMPOSIUM ON IMPLEMENTATION AND APPLICATION OF FUNCTIONAL LANGUAGES - IFL 2016 KU Leuven, Belgium In cooperation with ACM SIGPLAN August 31 - September 2, 2016 https://dtai.cs.kuleuven.be/events/ifl2016/ Scope The goal of the IFL symposia is to bring together researchers actively engaged in the implementation and application of functional and function-based programming languages. IFL 2016 will be a venue for researchers to present and discuss new ideas and concepts, work in progress, and publication-ripe results related to the implementation and application of functional languages and function-based programming. Peer-review Following the IFL tradition, IFL 2016 will use a post-symposium review process to produce the formal proceedings. All participants of IFL 2016 are invited to submit either a draft paper or an extended abstract describing work to be presented at the symposium. At no time may work submitted to IFL be simultaneously submitted to other venues; submissions must adhere to ACM SIGPLAN's republication policy: http://www.sigplan.org/Resources/Policies/Republication The submissions will be screened by the program committee chair to make sure they are within the scope of IFL, and will appear in the draft proceedings distributed at the symposium. Submissions appearing in the draft proceedings are not peer-reviewed publications. Hence, publications that appear only in the draft proceedings are not subject to the ACM SIGPLAN republication policy. After the symposium, authors will be given the opportunity to incorporate the feedback from discussions at the symposium and will be invited to submit a revised full article for the formal review process. From the revised submissions, the program committee will select papers for the formal proceedings considering their correctness, novelty, originality, relevance, significance, and clarity. The formal proceedings will appear in the International Conference Proceedings Series of the ACM Digital Library. Important dates August 1: Submission deadline draft papers August 3: Notification of acceptance for presentation August 5: Early registration deadline August 12: Late registration deadline August 22: Submission deadline for pre-symposium proceedings August 31 - September 2: IFL Symposium December 1: Submission deadline for post-symposium proceedings January 31, 2017: Notification of acceptance for post-symposium proceedings March 15, 2017: Camera-ready version for post-symposium proceedings Submission details Prospective authors are encouraged to submit papers or extended abstracts to be published in the draft proceedings and to present them at the symposium. All contributions must be written in English. Papers must use the new ACM two columns conference format, which can be found at: http://www.acm.org/publications/proceedings-template For the pre-symposium proceedings we adopt a 'weak' page limit of 12 pages. For the post-symposium proceedings the page limit of 12 pages is firm. Authors submit through EasyChair: https://easychair.org/conferences/?conf=ifl2016 Topics IFL welcomes submissions describing practical and theoretical work as well as submissions describing applications and tools in the context of functional programming. If you are not sure whether your work is appropriate for IFL 2016, please contact the PC chair at tom.schrijvers(a)cs.kuleuven.be. Topics of interest include, but are not limited to: - language concepts - type systems, type checking, type inferencing - compilation techniques - staged compilation - run-time function specialization - run-time code generation - partial evaluation - (abstract) interpretation - metaprogramming - generic programming - automatic program generation - array processing - concurrent/parallel programming - concurrent/parallel program execution - embedded systems - web applications - (embedded) domain specific languages - security - novel memory management techniques - run-time profiling performance measurements - debugging and tracing - virtual/abstract machine architectures - validation, verification of functional programs - tools and programming techniques - (industrial) applications Peter Landin Prize The Peter Landin Prize is awarded to the best paper presented at the symposium every year. The honored article is selected by the program committee based on the submissions received for the formal review process. The prize carries a cash award equivalent to 150 Euros. Programme committee Chair: Tom Schrijvers, KU Leuven, Belgium - Sandrine Blazy, University of Rennes 1, France - Laura Castro, University of A Coru√±a, Spain - Jacques, Garrigue, Nagoya University, Japan - Clemens Grelck, University of Amsterdam, The Netherlands - Zoltan Horvath, Eotvos Lorand University, Hungary - Jan Martin Jansen, Netherlands Defence Academy, The Netherlands - Mauro Jaskelioff, CIFASIS/Universidad Nacional de Rosario, Argentina - Patricia Johann, Appalachian State University, USA - Wolfram Kahl, McMaster University, Canada - Pieter Koopman, Radboud University Nijmegen, The Netherlands - Shin-Cheng Mu, Academia Sinica, Taiwan - Henrik Nilsson, University of Nottingham, UK - Nikolaos Papaspyrou, National Technical University of Athens, Greece - Atze van der Ploeg, Chalmers University of Technology, Sweden - Matija Pretnar, University of Ljubljana, Slovenia - Tillmann Rendel, University of T√ºbingen, Germany - Christophe Scholliers, Universiteit Gent, Belgium - Sven-Bodo Scholz, Heriot-Watt University, UK - Melinda Toth, Eotvos Lorand University, Hungary - Meng Wang, University of Kent, UK - Jeremy Yallop, University of Cambridge, UK Venue The 28th IFL will be held in association with the Faculty of Computer Science, KU Leuven, Belgium. Leuven is centrally located in Belgium and can be easily reached from Brussels Airport by train (~15 minutes). The venue in the Arenberg Castle park can be reached by foot, bus or taxi from the city center. See the website for more information on the venue.

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