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[ANNOUNCE] GHC 8.8.1 release candidate 1 is now available
by Ben Gamari 22 Jul '19

22 Jul '19

Hello everyone, The GHC team is pleased to announce the release candidate for GHC 8.8.1. The source distribution, binary distributions, and documentation are available at https://downloads.haskell.org/ghc/8.8.1-rc1 This release is the culmination of over 3000 commits by over one hundred contributors and has several new features and numerous bug fixes relative to GHC 8.6: * Profiling now works correctly on 64-bit Windows (although still may be problematic on 32-bit Windows due to platform limitations; see #15934) * A new code layout algorithm for amd64's native code generator * The introduction of a late lambda-lifting pass which may reduce allocations significantly for some programs. * Further work on Trees That Grow, enabling improved code re-use of the Haskell AST in tooling * More locations where users can write `forall` (GHC Proposal #0007) * A comprehensive audit of GHC's memory ordering barriers has been performed, resulting in a number of fixes that should significantly improve the reliability of programs on architectures with weakly-ordered memory models (e.g. PowerPC, many ARM and AArch64 implementations). * A long-standing linker limitation rendering GHCi unusable with projects with cyclic symbol dependencies has been fixed (#13786) * Further work on the Hadrian build system * Numerous bug-fixes As always, if anything looks amiss do let us know. Happy compiling! Cheers, - Ben [1] https://downloads.haskell.org/ghc/8.8.1-rc1/docs/html/users_guide/8.8.1-not…

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Translating a pre-image witness from agda to haskell
by Ruben Astudillo 22 Jul '19

22 Jul '19

Dear list I've been playing with agda lately, I've been following the tutorials on their homepage to get a grasp of dependent types. The exposition has been good and clear. Some techniques can be passed over to haskell by using GADTs and DataKinds. Some examples require singletons to have the same kind of quantification as in agda. Currently I am trying to write in haskell the following data type and function data Image {A B : Set} (f : A -> B) : B -> Set where im : (x : A) -> Image f (f x) inv : {A B : Set} (f : A -> B) (y : B) -> Image f y -> A inv f .(f x) (im x) = x The `Image` datatype correspond to the proposition that the function `f : A -> B` has a pre-image for certain element on `B`. This is witnessed only if the `im` data constructor exists. The `inv` function is there only to show how agda can know by the presence of the `im x` data constructor that the value of `y` cannot be other than `f x`, mind bending stuff. I've been trying to write this ADT on haskell. I haven't got luck in so far. The problem is that referring to a `type family` constructed from a term level function is not clear to me, even with singletons, as I cannot guarantee such type family is defined. Currently I got this data Image (f :: Type -> Type) Type where Im :: Proxy (Sing t1 -> Sing (f t1)) -> f t1 -> Image (Sing t1 -> Sing (f t1)) (f t1) Which isn't exactly what the agda version is. Does anyone has an idea on how to continue or has done this example before? I am perfectly OK with being told it's not possible yet or what should I read. -- -- Ruben -- PGP: 4EE9 28F7 932E F4AD

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Journeys in Computational Logic: Tributes to Roy Dyckhoff : CFP
by Ekaterina Komendantskaya 22 Jul '19

22 Jul '19

CALL FOR PARTICIPATION Journeys in Computational Logic: Tributes to Roy Dyckhoff at TABLEAUX 2019, the 28th International Conference on Automated Reasoning with Analytic Tableaux and Related Methods, Middlesex University, London https://tableaux2019.org/ Main conference: 3 September to 5 September 2019 Journeys in Computational Logic: 3 September 2019 Roy Dyckhoff (1948 - 2018) worked in logic and proof theory, having begun his career as a topologist and category theorist (for which one of his thesis advisors was Dana Scott). Much of his work concerned various aspects of intuitionistic logic, but he also contributed to work in programming languages, type theory, natural language processing, and model checking. The event will commemorate and celebrate Roy’s work, by speakers who have crossed paths with Roy, and/or whose work or scientific views have been influenced by him. The workshop will follow the Tableaux invited talks by Sara Negri and Stéphane Graham-Lengrand, also dedicated to Roy’s work and contribution to the field. The list of contributors is as follows: Marta Bilkova Alessio Guglielmi Jacob Howe Jael Kriener James McKinna Mehrnoosh Sadrzadeh Peter Schroeder-Heister Christian Urban SOCIAL EVENT The workshop will be followed by the Tableaux welcome reception. ORGANISERS If you have any questions, or wish to contribute a talk, please contact the organisers: Ekaterina Komendantskaya: http://www.macs.hw.ac.uk/~ek19/ Stephane Graham-Lengrand: http://www.csl.sri.com/users/sgl/ Mehrnoosh Sadrzadeh: https://msadrzadeh.com/

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ANNOUNCE: lens-family 2.0.0 anniversary edition!
by roconnor＠theorem.ca 20 Jul '19

20 Jul '19

In celebration of the 10th anniversary of Twan van Laarhoven's seminal blog post ``CPS based functional references''[1], I am releasing version 2.0 of lens-family[2] and lens-family-core[3] packages. This new release continues to explore the design of Van Laarhoven style optics with new support for adapters, grates, grids[4], and prisms. To bring support to these new optics necessarily means moving a little further away from syntactic compatibility with Kmett's lens library. In particular, lens-family's 'under' is unrelated to Kmett's lens library's 'under' combinator. Nonetheless the 'under' combinator plays a crucial role in lens-family as a dual to the 'over' combinator and this naming is hard to resist despite the conflict. This new version comes with some minor incompatibilities with the version 1.2 library that may require user updates. See <https://hackage.haskell.org/package/lens-family-2.0.0/changelog>. [1]<https://www.twanvl.nl/blog/haskell/cps-functional-references> [2]<https://hackage.haskell.org/package/lens-family-2.0.0> [3]<https://hackage.haskell.org/package/lens-family-core-2.0.0> [4]A grid is an optic that is both a grate and a traversal. -- Russell O'Connor <http://r6.ca/>

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Re: [Haskell-cafe] ANNOUNCE: lens-family 2.0.0 anniversary edition!
by roconnor＠theorem.ca 20 Jul '19

20 Jul '19

On Fri, 19 Jul 2019, Artyom Kazak wrote: > > Naturally, users can stick with the 1.2 release of lens-family if it > > suits their needs. > You can not easily have two versions of the same library in your dependency tree. So, only application developers will be able to stick to the 1.2 release without creating obstacles for > the rest of the ecosystem. I see. I hadn't given that much consideration. In that case, I apologize for the inconvience this upgrade may cause. I'll try to be more mindful of this in the future. -- Russell O'Connor <http://r6.ca/> ``My friends, love is better than anger. Hope is better than fear. Optimism is better than dispair. So let us be loving, hopeful and optimistic. And we'll change the world.'' -- Jack Layton

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[CC2020] Call for Papers for the ACM SIGPLAN 2020 International Conference on Compiler Construction
by Gabriel Rodríguez Álvarez 18 Jul '19

18 Jul '19

ACM SIGPLAN 2020 International Conference on Compiler Construction (CC'20) co-located with CGO, PPoPP and HPCA San Diego, CA, USA February 22 - 23, 2020 https://cc-conference.github.io The ACM SIGPLAN 2020 International Conference on Compiler Construction (CC 2020) is interested in work on processing programs in the most general sense: analyzing, transforming or executing input programs that describe how a system operates, including traditional compiler construction as a special case. Original contributions are solicited on the topics of interest which include, but are not limited to: - Compilation and interpretation techniques, including program representation, analysis, and transformation; code generation, optimization, and synthesis; the verification thereof - Run-time techniques, including memory management, virtual machines, and dynamic and just-in-time compilation - Programming tools, including refactoring editors, checkers, verifiers, compilers, debuggers, and profilers - Techniques for specific domains, such as secure, parallel, distributed, embedded or mobile environments - Design and implementation of novel language constructs, programming models, and domain-specific languages CC 2020 is the 29th edition of the conference. From this year onwards, CC is an ACM SIGPLAN conference and will implement guidelines and procedures recommended by SIGPLAN https://www.sigplan.org. ================================================================================================= To subscribe to the CC announce mailing list, see cc_conference_announce(a)googlegroups.com To subscribe to the CC announce Twitter account, see @cc2020conf (https://twitter.com/cc2020conf) ======================================================================================= IMPORTANT DATES Abstract Submission: 23 October 2019 Paper Submission : 30 October 2019 Rebuttal : 4-6 December 2019 Artifact Submission: 13 December 2019 Author Notification: 24 December 2019 Final papers due : 15 January 2020 Conference : 22–23 February 2020 Authors are encouraged to submit their artifacts for the Artifact Evaluation (AE). The Artifact Evaluation process is run by a separate committee whose task is to assess how the artifacts support the work described in the papers. To ease the organization of the AE committee, we kindly ask authors to submit their artifact at the latest 10 days after the rebuttal. Papers that go through the Artifact Evaluation process successfully will receive a seal of approval printed on the papers themselves. Additional information will be made available on the CC AE web page. ORGANIZERS General Chair Louis-Noel Pouchet Colorado State University <pouchet AT colostate.edu> Program Chair Alexandra Jimborean Uppsala University <alexandra.jimborean AT it.uu.se> Artifact Evaluation Chairs Michel Steuwer University of Glasgow <Michel.Steuwer AT glasgow.ac.uk> Martin Kong University of Oklahoma Publicity Chair Gabriel Rodriguez University of A Coruna Web Chair Mihail Popov Uppsala University Steering Committee Bjorn Franke University of Edinburgh <bfranke AT inf.ed.ac.uk> Sebastian Hack Saarland University Manuel Hermenegildo IMDEA SW Institute and Technical U. of Madrid Peng Wu Huawei America Research Lab Ayal Zaks Intel and Technion, Israel Jingling Xue University of New South Wales, Australia Christophe Dubach University of Edinburgh Nelson J. Amaral University of Alberta Milind Kulkarni Purdue University Program Committee Apan Qasem AMD/Texas State University Bernhard Scholz University of Sydney Bettina Heim Microsoft Bilha Mendelson Optitura Brian Demsky UC Irvine Changhee Jung Virginia Tech Christian Schulte KTH EJ Park Los Alamos National Laboratory Delphine Demange Inria Dongyoon Lee Virginia Tech Fernando Magno Quintao Pereira UFMG Brazil Haowei Wu Google Manuel Hermenegildo IMDEA and T.U. Madrid Matin Hashemi Sharif University of Technology Michel Steuwer University of Glasgow Mila Dalla Preda University of Verona Nelson J. Amaral University of Alberta Philippe Clauss University of Strasbourg Pavlos Petoumenos University of Edinburgh Rumyana Neykova Brunel London Santosh Nagarakatte Rutgers University Sebastian Hack University of Saarland Tomofumi Yuki Inria Xu Liu College of William and Mary

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MPC 2019 - Call for Participation
by Graham Hutton 18 Jul '19

18 Jul '19

Dear all, Registration is now open for the Mathematics of Program Construction (MPC) conference in Portugal. MPC 2019 will feature 15 research papers and 4 keynotes, and is co-located with Formal Methods 2019 and many other events. See you in Porto! https://tinyurl.com/MPC-Porto Best wishes, Graham Hutton ====================================================================== *** CALL FOR PARTICIPATION -- MPC 2019 *** 13th International Conference on Mathematics of Program Construction 7-9 October 2019, Porto, Portugal Co-located with Formal Methods 2019 https://tinyurl.com/MPC-Porto ====================================================================== PROGRAM: https://tinyurl.com/yxvvc5vb ACCEPTED PAPERS: https://tinyurl.com/yyuhy8ze REGISTRATION AND TRAVEL: https://tinyurl.com/y4uetlsr KEYNOTE SPEAKERS: Assia Mahboubi (MPC) INRIA, France Annabelle McIver (MPC) Macquarie University, Australia Tony Hoare (UTP) Oxford University, UK Shriram Krishnamurthi (FM) Brown University, USA BACKGROUND: The International Conference on Mathematics of Program Construction (MPC) aims to promote the development of mathematical principles and techniques that are demonstrably practical and effective in the process of constructing computer programs. MPC 2019 will be held in Porto, Portugal from 7-9 October 2019, and is co-located with the International Symposium on Formal Methods, FM 2019. Previous conferences were held in Königswinter, Germany (2015); Madrid, Spain (2012); Québec City, Canada (2010); Marseille, France (2008); Kuressaare, Estonia (2006); Stirling, UK (2004); Dagstuhl, Germany (2002); Ponte de Lima, Portugal (2000); Marstrand, Sweden (1998); Kloster Irsee, Germany (1995); Oxford, UK (1992); Twente, The Netherlands (1989). PROGRAM COMMITTEE: Patrick Bahr IT University of Copenhagen, Denmark Richard Bird University of Oxford, UK Corina Cîrstea University of Southampton, UK Brijesh Dongol University of Surrey, UK João F. Ferreira University of Lisbon, Portugal Jennifer Hackett University of Nottingham, UK William Harrison University of Missouri, USA Ralf Hinze University of Kaiserslautern, Germany Zhenjiang Hu National Institute of Informatics, Japan Graham Hutton (chair) University of Nottingham, UK Cezar Ionescu University of Oxford, UK Mauro Jaskelioff National University of Rosario, Argentina Ranjit Jhala University of California, USA Gabriele Keller Utrecht University, The Netherlands Ekaterina Komendantskaya Heriot-Watt University, UK Chris Martens North Carolina State University, USA Bernhard Möller University of Augsburg, Germany Shin-Cheng Mu Academia Sinica, Taiwan Mary Sheeran Chalmers University of Technology, Sweden Alexandra Silva University College London, UK Georg Struth University of Sheffield, UK For any queries about the program please contact the program chair, Graham Hutton <graham.hutton(a)nottingham.ac.uk>. CONFERENCE VENUE: The conference will be held at the Alfândega Porto Congress Centre, a 150 year old former custom's house located in the historic centre of Porto on the bank of the river Douro. The venue was renovated by a Pritzer prize winning architect and has received many awards. LOCAL ORGANISER: José Nuno Oliveira University of Minho, Portugal For any queries about local issues please contact the local organiser, José Nuno Oliveira <jno(a)di.uminho.pt>. ====================================================================== 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 contact the sender and delete the email and attachment. Any views or opinions expressed by the author of this email do not necessarily reflect the views of the University of Nottingham. Email communications with the University of Nottingham may be monitored where permitted by law.

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Second Call for Participation: ICFP 2019
by Sam Tobin-Hochstadt 17 Jul '19

17 Jul '19

** The Early Registration deadline is tomorrow! ** ===================================================================== Call for Participation ICFP 2019 24th ACM SIGPLAN International Conference on Functional Programming and affiliated events August 18 - August 23, 2019 Berlin, Germany http://icfp19.sigplan.org/ Early Registration until July 18! ===================================================================== ICFP provides a forum for researchers and developers to hear about the latest work on the design, implementations, principles, and uses of functional programming. The conference covers the entire spectrum of work, from practice to theory, including its peripheries. This year, ICFP is co-located with BOBKonf! * Overview and affiliated events: http://icfp19.sigplan.org/home * Program: http://icfp19.sigplan.org/program/program-icfp-2019 * Accepted papers: http://icfp19.sigplan.org/track/icfp-2019-papers * Registration is available via: https://regmaster4.com/2019conf/ICFP19/register.php Early registration ends 18 July, 2019. * Programming contest: https://icfpcontest2019.github.io/ * Student Research Competition: https://icfp19.sigplan.org/track/icfp-2019-Student-Research-Competition * Follow us on Twitter for the latest news: http://twitter.com/icfp_conference In addition to BOBKonf (8/21), there are several events co-located with ICFP: * Erlang Workshop (8/18) * Functional Art, Music, Modeling and Design (8/23) * Functional High-Performance and Numerical Computing (8/18) * Haskell Implementors' Workshop (8/23) * Haskell Symposium (8/22-8/23) * miniKanren Workshop (8/22) * ML Family Workshop (8/22) * OCaml Workshop (8/23) * Programming Languages Mentoring Workshop (8/18) * Scheme Workshop (8/18) * Type-Driven Development (8/18) ### ICFP Organizers General Chair: Derek Dreyer (MPI-SWS, Germany) Artifact Evaluation Co-Chairs: Simon Marlow (Facebook, UK) Industrial Relations Chair: Alan Jeffrey (Mozilla Research, USA) Programming Contest Organiser: Ilya Sergey (Yale-NUS College, Singapore) Publicity and Web Chair: Sam Tobin-Hochstadt (Indiana University, USA) Student Research Competition Chair: William J. Bowman (University of British Columbia, Canada) Workshops Co-Chair: Christophe Scholliers (Universiteit Gent, Belgium) Jennifer Hackett (University of Nottingham, UK) Conference Manager: Annabel Satin (P.C.K.) ### PACMPL Volume 3, Issue ICFP 2019 Principal Editor: François Pottier (Inria, France) Review Committee: Lennart Beringer (Princeton University, United States) Joachim Breitner (DFINITY Foundation, Germany) Laura M. Castro (University of A Coruña, Spain) Ezgi Çiçek (Facebook London, United Kingdom) Pierre-Evariste Dagand (LIP6/CNRS, France) Christos Dimoulas (Northwestern University, United States) Jacques-Henri Jourdan (CNRS, LRI, Université Paris-Sud, France) Andrew Kennedy (Facebook London, United Kingdom) Daan Leijen (Microsoft Research, United States) Kazutaka Matsuda (Tohoku University, Japan) Bruno C. d. S. Oliveira (University of Hong Kong, China) Klaus Ostermann (University of Tübingen, Germany) Jennifer Paykin (Galois, United States) Frank Pfenning (Carnegie Mellon University, USA) Mike Rainey (Indiana University, USA) Chung-chieh Shan (Indiana University, USA) Sam Staton (University of Oxford, UK) Pierre-Yves Strub (Ecole Polytechnique, France) German Vidal (Universitat Politecnica de Valencia, Spain) External Review Committee: Michael D. Adams (University of Utah, USA) Robert Atkey (University of Strathclyde, IK) Sheng Chen (University of Louisiana at Lafayette, USA) James Cheney (University of Edinburgh, UK) Adam Chlipala (Massachusetts Institute of Technology, USA) Evelyne Contejean (LRI, Université Paris-Sud, France) Germán Andrés Delbianco (IRIF, Université Paris Diderot, France) Dominique Devriese (Vrije Universiteit Brussel, Belgium) Richard A. Eisenberg (Bryn Mawr College, USA) Conal Elliott (Target, USA) Sebastian Erdweg (Delft University of Technology, Netherlands) Michael Greenberg (Pomona College, USA) Adrien Guatto (IRIF, Université Paris Diderot, France) Jennifer Hackett (University of Nottingham, UK) Troels Henriksen (University of Copenhagen, Denmark) Chung-Kil Hur (Seoul National University, Republic of Korea) Roberto Ierusalimschy (PUC-Rio, Brazil) Ranjit Jhala (University of California, San Diego, USA) Ralf Jung (MPI-SWS, Germany) Ohad Kammar (University of Oxford, UK) Oleg Kiselyov (Tohoku University, Japan) Hsiang-Shang ‘Josh’ Ko (National Institute of Informatics, Japan) Ondřej Lhoták (University of Waterloo, Canada) Dan Licata (Wesleyan University, USA) Geoffrey Mainland (Drexel University, USA) Simon Marlow (Facebook, UK) Akimasa Morihata (University of Tokyo, Japan) Shin-Cheng Mu (Academia Sinica, Taiwan) Guillaume Munch-Maccagnoni (Inria, France) Kim Nguyễn (University of Paris-Sud, France) Ulf Norell (Gothenburg University, Sweden) Atsushi Ohori (Tohoku University, Japan) Rex Page (University of Oklahoma, USA) Zoe Paraskevopoulou (Princeton University, USA) Nadia Polikarpova (University of California, San Diego, USA) Jonathan Protzenko (Microsoft Research, USA) Tiark Rompf (Purdue University, USA) Andreas Rossberg (Dfinity, Germany) KC Sivaramakrishnan (University of Cambridge, UI) Nicholas Smallbone (Chalmers University of Technology, Sweden) Matthieu Sozeau (Inria, France) Sandro Stucki (Chalmers | University of Gothenburg, Sweden) Don Syme (Microsoft, UK) Zachary Tatlock (University of Washington, USA) Sam Tobin-Hochstadt (Indiana University, USA) Takeshi Tsukada (University of Tokyo, Japan) Tarmo Uustalu (Reykjavik University, Iceland) Benoit Valiron (LRI, CentraleSupelec, Univ. Paris Saclay, France) Daniel Winograd-Cort (University of Pennsylvania, USA) Nicolas Wu (University of Bristol, UK)

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Benefits and use cases for strong mobility in presence of closure serialization
by Станислав Черничкин 17 Jul '19

17 Jul '19

Benefits and use cases for strong mobility in presence of closure serialization I read a paper about strong mobility in Haskell http://www.dcs.gla.ac.uk/~trinder/papers/strongm.pdf and I wondering what benefits it gives in presence of closure serialization? I guess for some languages strong mobility could be only way to transfer execution state of program, e.g. [Mobile Pascal;)] program Test; var a: Integer; begin readln(a); // acquiring on current host moveTo("anotherHost"); // transfering state and terminating writeln(a); // printing on another host end. but in Haskell same program can be written just using rfork :: Host -> IO () -> IO (): main = do a <- readLn rfork AnotherHost $ do print a The difference comparing to moveTo :: Host -> IO () version is purely syntactic: main = do a <- readLn moveTo AnotherHost print a -- Sincerely, Stanislav Chernichkin.

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Re: [Haskell-cafe] Haskell-Cafe Digest, Vol 191, Issue 12
by Information The FLOSS 17 Jul '19

17 Jul '19

Bu ileti The FLOSS Information'a gönderdiğiniz ileti sonucunda otomatik olarak oluşturuldu. Bu iletiye yanıt vermenize gerek yoktur. Bu iletiyi gönderdiğiniz için teşekkür ederiz. 4 gün içerisinde yanıtlamaya çalışacağız. Eğer 4 gün içinde yanıt gelmezse tekrar ileti gönderebilirsiniz. Sık Sorulabilecek Sorular: https://theflossinformation.gitlab.io/sik-sorulabilecek-sorular.html Hakkımızda: https://theflossinformation.gitlab.io/hakkimizda.html Bize Ulaşın: https://theflossinformation.gitlab.io/bize-ulasin.html Saygılarımızla, The FLOSS Information https://theflossinformation.gitlab.io/

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