January 2018 - Haskell

Call for Conference Grant Applications (Inclusiveness Target Countries)
by Ambrus Kaposi 05 Nov '19

05 Nov '19

Call for Conference Grant Applications The European research network on types for programming and verification (EUTypes COST Action, https://eutypes.cs.ru.nl) supports attendance of young researchers presenting work on type theory at international conferences via travel grants. The rules are described here: https://eutypes.cs.ru.nl/ConfGrants The main points are: * Only researchers from ITCs participating in the action are eligible. As of September 2017, the ITCs involved in EUTypes are: Bosnia and Herzegovina, Czechia, Estonia, Hungary, Lithuania, Macedonia, Poland, Portugal, Romania, Serbia, Slovenia. * Only PhD students and Early Career Investigators (researchers whose PhD degree is at most 8 years old) are eligible. * The grantee must give a talk or present a poster on the topic of type theory. Applications have to be submitted through the e-COST system: https://e-services.cost.eu/conferencegrant Please inform researchers in your country who might be interested. Many thanks, Ambrus Kaposi EUTypes conference grant coordinator

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LiftA2 over fmap
by Damien BIHEL 30 Jan '18

30 Jan '18

In the documentation here <http://hackage.haskell.org/package/base-4.10.1.0/docs/Control-Applicative.h…> it's written that for some functors liftA2 has better performance than fmap. Does anyone have any examples ? Regards, -- Damien Bihel R&D (Research & Development) Engineer at ELRA (European Language Resources Association) E-Mail: biheldamien(a)gmail.com

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SPLASH 2018: 1st Combined Call for Contributions
by SPLASH Publicity 29 Jan '18

29 Jan '18

ACM SIGPLAN SPLASH 2018 November 4-9, 2018 Boston, MA, USA http://2018.splashcon.org The ACM SIGPLAN Conference on Systems, Programming, Languages and Applications: Software for Humanity (SPLASH) embraces all aspects of software construction, to make it the premier conference at the intersection of programming, languages, and software engineering. We invite high quality submissions describing original and unpublished work. Combined Call for Contributions: * SPLASH Workshops * PACMPL Issue OOPSLA * Onward! Papers * Onward! Essays * Dynamic Languages Symposium (DLS) * Generative Programming: Concepts & Experiences (GPCE) * Software Language Engineering (SLE) * SPLASH-E * Posters * Doctoral Symposium * Student Research Competition * Student Volunteers ## SPLASH Workshops Following its long-standing tradition, SPLASH 2018 will host a variety of high quality workshops, allowing their participants to meet and discuss research questions with peers, to mature new and exciting ideas, and to build up communities and start new collaborations. SPLASH workshops complement the main tracks of the conference and provide meetings in a smaller and more specialized setting. Workshops cultivate new ideas and concepts for the future, optionally recorded in formal proceedings. Submissions are currently being accepted on “a rolling basis” with 6 out of 15 available slots already filled by the middle of January. The rolling call will close on Sat March 3, 2018. http://2018.splashcon.org/track/splash-2018-Workshops ## PACMPL Issue OOPSLA Papers may target any stage of software development, including requirements, modeling, prototyping, design, implementation, generation, analysis, verification, testing, evaluation, maintenance, and reuse of software systems. Contributions may include the development of new tools (such as language front-ends, program analyses, and runtime systems), new techniques (such as methodologies, design processes, and code organization approaches), new principles (such as formalisms, proofs, models, and paradigms), and new evaluations (such as experiments, corpora analyses, user studies, and surveys). Submissions due: Mon April 16, 2018 http://2018.splashcon.org/track/splash-2018-OOPSLA ## Onward! Papers Onward! is a premier multidisciplinary conference focused on everything to do with programming and software: including processes, methods, languages, communities, and applications. Onward! is more radical, more visionary, and more open than other conferences to ideas that are well-argued but not yet proven. We welcome different ways of thinking about, approaching, and reporting on programming language and software engineering research. Submissions due: Mon April 23, 2018 https://2018.onward-conference.org/track/onward-2018-papers ## Onward! Essays Onward! Essays is looking for clear and compelling pieces of writing about topics important to the software community. An essay can be long or short. An essay can be an exploration of the topic and its impact, or a story about the circumstances of its creation; it can present a personal view of what is, explore a terrain, or lead the reader in an act of discovery; it can be a philosophical digression or a deep analysis. It can describe a personal journey, perhaps the one the author took to reach an understanding of the topic. The subject area—software, programming, and programming languages—should be interpreted broadly and can include the relationship of software to human endeavors, or its philosophical, sociological, psychological, historical, or anthropological underpinnings. Submissions due: Mon April 23, 2018 https://2018.onward-conference.org/track/onward-2018-Onward-Essays ## Dynamic Languages Symposium (DLS) >From Lisp, Snobol, and Smalltalk to Python, Racket, and Javascript, Dynamic Languages have been playing a fundamental role both in programming research and practice. DLS is the premier forum for researchers and practitioners to share research and experience on all aspects of Dynamic Languages. DLS invites high quality papers reporting original research and experience related to the design, implementation, and applications of dynamic languages. Submissions due: Sun July 1, 2018 http://www.dynamic-languages-symposium.org/dls-18/index.html ## Generative Programming: Concepts & Experiences (GPCE) The International Conference on Generative Programming: Concepts & Experience (GPCE) is a venue for researchers and practitioners interested in techniques and tools for code generation, language implementation, and metaprogramming. GPCE seeks conceptual, theoretical, empirical, and technical contributions to its topics of interest, which include but are not limited to (i) program transformation, staging, macro systems, preprocessors, program synthesis, and code-recommendation systems, (ii) domain-specific languages, language embedding, language design, and language workbenches, (iii) feature-oriented programming, domain engineering, and feature interactions, (iv) applications and properties of code generation, language implementation, and product-line development. Abstracts due: Fri June 29, 2018 Submissions due: Fri July 6, 2018 http://2018.splashcon.org/track/gpce-2018 ## Software Language Engineering (SLE) Software Language Engineering (SLE) is the discipline of engineering languages and their tools required for the creation of software. It abstracts from the differences between programming languages, modelling languages, and other software languages, and emphasizes the engineering facet of the creation of such languages, that is, the establishment of the scientific methods and practices that enable the best results. SLE 2018 solicits high quality contributions in areas ranging from theoretical and conceptual contributions, to tools, techniques, and frameworks in the domain of software language engineering. Abstracts due: Fri June 29, 2018 Submissions due: Fri July 6, 2018 http://2018.splashcon.org/track/sle-2018/papers ## Posters The SPLASH Poster track provides an excellent forum for authors to present their recent or ongoing projects in an interactive setting, and receive feedback from the community. We invite submissions covering any aspect of programming, systems, languages and applications. The goal of the poster session is to encourage and facilitate small groups of individuals interested in a technical area to gather and interact at any desired level of detail. To further facilitate, we will also host 15-minute demo sessions for interested presenters. The poster session and demo presentations are held early in the conference to promote continued discussion among interested parties. Submissions due: Sat September 22, 2018 http://2018.splashcon.org/track/splash-2018-Posters ## Doctoral Symposium The SPLASH Doctoral Symposium provides students with useful guidance for completing their dissertation research and beginning their research careers. The symposium will provide an interactive forum for doctoral students who have progressed far enough in their research to have a structured proposal, but will not be defending their dissertation in the next 12 months. Submissions due: Fri July 20, 2018 http://2018.splashcon.org/track/splash-2018-Doctoral-Symposium ## Student Research Competition The ACM Student Research Competition (SRC), sponsored by Microsoft Research, offers a unique forum for ACM student members at the undergraduate and graduate levels to present their original research at SPLASH before a panel of judges and conference attendees. The SRC gives visibility to not only up-and-coming young researchers, but also exposes them to the field of computer science research and its community. This competition also gives students an opportunity to discuss their research with experts in their field, get feedback, and to help them sharpen their communication and networking skills. Submissions due: Fri July 27, 2018 https://2018.splashcon.org/track/splash-2018-Student-Research-Competition ## Student Volunteers The SPLASH Student Volunteers program provides an opportunity for students from around the world to associate with some of the leading personalities in industry and research in the following areas: programming languages, object-oriented technology and software development. Student volunteers contribute to the smooth running of the conference by performing tasks such as: assisting with registration, providing information about the conference to attendees, assisting session organizers and monitoring sessions. Detailed information on how to apply will be available on the main conference page in March 2018. Estimated deadline for the SV applications will be towards the end of September 2018. https://2018.splashcon.org/track/splash-2018-Student-Volunteers ## Information Contact: publicity(a)splashcon.org Website: http://2018.splashcon.org Location: Boston Park Plaza Hotel Boston, MA USA ## Organization SPLASH General Chair: * Jan Vitek (Northeastern University) OOPSLA Program Chair: * Manu Sridharan (Uber) Onward! Papers Chair: * Elisa Gonzalez Boix (Vrije Universiteit Brussel) Onward! Essays Chair: * Richard P. Gabriel (Dream Songs, Inc & HPI) DLS Program Chair: * Tim Felgentreff (Oracle Labs, Potsdam) GPCE General Chair: * Matthew Flatt (University of Utah) GPCE Program Chair: * Sebastian Erdweg (TU Delft) SLE General Chair: * David Pearce (Victoria University of Wellington) SLE Program Co-Chairs: * Tanja Mayerhofer (TU Wien) * Friedrich Steimann (Fernuniversität) SPLASH-I Co-Chairs: * Karim Ali (University of Alberta) * Michael Carbin (MIT) Workshops Co-Chairs: * Arjun Guha (University of Massachusetts Amherst) * Alex Potanin (Victoria University of Wellington) OOPLSA Artifact Evaluation Co-Chairs: * Sam Tobin-Hochstadt (Indiana University) * Jan Vitek (Northeastern University) Posters Co-Chairs: * Paley Li (Czech Technical University in Prague) * Konrad Siek (Czech Technical University in Prague) Doctoral Symposium Chair: * Philipp Haller (KTH Royal Institute of Technology) Student Research Competition Co-Chairs: * Shan Shan Huang (LogicBlox) * Jay McCarthy (University of Massachusetts Lowell) Student Volunteers Co-Chairs: * Juliana Franco (Imperial College London) * Petr Maj (ReactorLabs) Publications Chair: * Tijs van der Storm (CWI & University of Groningen) * Fabio Niephaus (Hasso Plattner Institute, University of Potsdam) Publicity Co-Chairs: * Jonathan Bell (George Mason University) * Celeste Hollenbeck (Northeastern University) Housing Chair: * Ben Greenman (Northeastern University) Diversity Chair: * Etiene Dalcol (Red Badger) Accessibility Chair: * Justin Slepak (Northeastern University) Sponsorships Co-Chairs: * Tocker Taft (AdaCore) * Heather Miller (Northeastern University) Video Co-Chairs: * Benjamin Chung (Northeastern University) * Leif Andersen (Northeastern University) Web Co-Chairs: * Aviral Goel (Northeastern University) * Filip Krikava (Czech Technical University)

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PPDP 2018: First Call for Papers
by David Sabel 23 Jan '18

23 Jan '18

====================================================================== PPDP 2018: First Call for Papers ====================================================================== 20th International Symposium on Principles and Practice of Declarative Programming Frankfurt am Main, Germany, 3-5 September 2018 http://ppdp-lopstr-18.cs.uni-frankfurt.de/ppdp18.html Frankfurt, Germany, September 4-6, 2018 (co-located with LOPSTR 2018 and WFLP 2018) ====================================================================== The PPDP 2018 symposium brings together researchers from the declarative programming communities, including those working in the functional, logic, answer-set, and constraint handling programming paradigms. The goal is to stimulate research in the use of logical formalisms and methods for analyzing, performing, specifying, and reasoning about computations, including mechanisms for concurrency, security, static analysis, and verification. Submissions are invited on all topics related to declaractive programming, from principles to practice, from foundations to applications. Topics of interest include, but are not limited to - Language Design: domain-specific languages; interoperability; concurrency, parallelism, and distribution; modules; probabilistic languages; reactive languages; database languages; knowledge representation languages; languages with objects; language extensions for tabulation; metaprogramming. - Implementations: abstract machines; interpreters; compilation; compile-time and run-time optimization; memory management. - Foundations: types; logical frameworks; monads and effects; semantics. - Analysis and Transformation: partial evaluation; abstract interpretation; control flow; data flow; information flow; termination analysis; resource analysis; type inference and type checking; verification; validation; debugging; testing. - Tools and Applications: programming and proof environments; verification tools; case studies in proof assistants or interactive theorem provers; certification; novel applications of declarative programming inside and outside of CS; declarative programming pearls; practical experience reports and industrial application; education. The PC chair will be happy to advise on the appropriateness of a topic. PPDP will be co-located with the 28th Int'l Symp. on Logic-Based Program Synthesis and Transformation (LOPSTR 2018). Submission Categories ===================== Submissions can be made in three categories: regular Research Papers, System Descriptions, and Experience Reports. Submissions of Research Papers must present original research which is unpublished and not submitted elsewhere. They must not exceed 12 pages ACM style 2-column (including figures, but excluding bibliography). Work that already appeared in unpublished or informally published workshop proceedings may be submitted (please contact the PC chair in case of questions). Research papers will be judged on originality, significance, correctness, clarity, and readability. Submission of System Descriptions must describe a working system whose description has not been published or submitted elsewhere. They must not exceed 10 pages and should contain a link to a working system. System Descriptions must be marked as such at the time of submission and will be judged on originality, significance, usefulness, clarity, and readability. Submissions of Experience Reports are meant to help create a body of published, refereed, citable evidence where declarative programming such as functional, logic, answer-set, constraint programming, etc., is used in practice. They must not exceed 5 pages **including references**. Experience Reports must be marked as such at the time of submission and need not report original research results. They will be judged on significance, usefulness, clarity, and readability. Possible topics for an Experience Report include, but are not limited to: insights gained from real-world projects using declarative programming comparison of declarative programming with conventional programming in the context of an industrial project or a university curriculum curricular issues encountered when using declarative programming in education real-world constraints that created special challenges for an implementation of a declarative language or for declarative programming in general novel use of declarative programming in the classroom programming pearl that illustrates a nifty new data structure or programming technique. Supplementary material may be provided in a clearly marked appendix beyond the above-mentioned page limits. Reviewers are not required to study any material beyond the respective page limit. Format of a submission ====================== For each paper category, you must use the most recent version of the "Current ACM Master Template" which is available at <https://www.acm.org/publications/proceedings-template>. The most recent version at the time of writing is 1.48. You must use the LaTeX sigconf proceedings template as the conference organizers are unable to process final submissions in other formats. In case of problems with the templates, contact [ACM's TeX support team atAptara](mailto:acmtexsupport@aptaracorp.com). Authors should note [ACM's statement on author'srights](http://authors.acm.org/) which apply to final papers. Submitted papers should meet the requirements of [ACM's plagiarism policy](http://www.acm.org/publications/policies/plagiarism_policy). Requirements for publication ============================ At least one author of each accepted submission will be expected to attend and present the work at the conference. The pc chair may retract a paper that is not presented. The pc chair may also retract a paper if complaints about the paper's correctness are raised which cannot be resolved by the final paper deadline. Important dates =============== - 23.04.2018 paper submission - 14.06.2018 rebuttal period (48 hours) - 25.06.2018 notification - 16.07.2018 final papers - 03.09.2018 conference starts

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SLURP: a single unified registry for Haskell packages
by Simon Peyton Jones 22 Jan '18

22 Jan '18

Friends Hackage has been extraordinarily successful as a single repository through which to share Haskell packages. It has supported the emergence of variety of tools to locate Haskell packages, build them and install them (cabal-install, Stack, Nix, ...). But in recent years there has been increasing friction over, * Hackage's policies, especially concerning version bounds; * Hackage's guarantees, especially around durability of package content and metadata; * Hackage's features, especially the visual presentation and package documentation. If we do not resolve this friction, it seems likely that the Haskell library ecosystem will soon "fork", with two separate repositories, one optimised for Cabal and one for Stack. This would be extremely counter-productive for Haskell users. Thus motivated, over the last few months we have talked a lot to colleagues, including ones in the Hackage and Stack communities. We have emerged with SLURP, a proposal that could go a long way towards supporting the upsides of a diverse ecosystem, without the sad downsides of forking into mutually-exclusive sub-communities. Here is the SLURP proposal<https://github.com/simonmar/ecosystem-proposals/blob/slurp/proposals/0000-s…>. We invite the Haskell community to debate it. SLURP is meant to enable both Hackage and Stackage (and perhaps more services in the future) to in the future make choices autonomously without hurting other package services. But it will only work if the implementors of both Hackage and Stackage are willing to participate. We respect their autonomy in this matter, but we urge them to give this proposal serious consideration in the best interests of the community and Haskell's success. We have carefully designed SLURP to be as minimal and non-invasive as possible, so that it can be adopted without much trouble. Of course, we are open to debate about the specific details. We do have an offer from someone willing to implement SLURP. We also strongly urge members of the community to express clear views about the importance --- or otherwise --- of adopting something like SLURP. You are, after all, the community that GHC, Hackage, Stackage, Cabal, etc are designed to serve, so your views about what best meets your needs are critically important. Mathieu Boespflug (@mboes<https://github.com/boes>) Manuel Chakravarty (@mchakravarty<https://github.com/mchakravarty>) Simon Marlow (@simonmar<https://github.com/simonmar>) Simon Peyton Jones (@simonpj<https://github.com/simonpj>) Alan Zimmerman (@alanz<https://github.com/alanz>)

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A small milestone
by Simon Peyton Jones 18 Jan '18

18 Jan '18

Cherished friends Today is my sixtieth birthday. It is just over forty years since Phil and I called in at Yale on my way to FPCA, and floated the idea of Haskell with Paul Hudak<https://www.microsoft.com/en-us/research/publication/a-history-of-haskell-b…>. (It wasn't called Haskell then, of course.) Rather a lot of water has flowed under the bridge since then. GHC's bug tracker is up to 14,683 tickets; I have read every one of them. But the best thing is Haskell's rich community of smart, motivated, passionate, and friendly colleagues. There was a time when I knew every Haskell programmer on the planet, but we are far, far beyond that point. Now it's beyond me even to keep up with the huge wave of elegant and creative ideas, tools, libraries, and blog posts that you generate. (Kudos to Taylor - and doubtless other colleagues -- for the Haskell Weekly News<https://haskellweekly.news/>, which I love.) But despite its size, it's a community that is still characterised by a love of elegance, and a desire to distil the essence of an idea and encapsulate it in an abstraction, all tempered with respect and tolerance. We don't always live up to these ideals, but by and large we do. Thank you all. Onward and upward! Simon PS: as birthday recreation I'm working on https://ghc.haskell.org/trac/ghc/wiki/QuantifiedContexts

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SBLP 2018 Call for Papers - XXII Brazilian Symposium on Programming Languages
by Carlos Camarao 17 Jan '18

17 Jan '18

*SBLP 2018: XXII Brazilian Symposium on Programming Languages* ________________________________________________________________________________ Universidade de São Paulo - ICMC/USP São Carlos, Brazil, September 20-21, 2018 Conference website http://www.sbc.org.br/cbsoft2018 Submission link https://easychair.org/conferences/?conf=sblp2018 SBLP 2018 is the 22nd edition of the Brazilian Symposium on Programming Languages. It is promoted by the Brazilian Computer Society (SBC) and constitutes a forum for researchers, students and professionals to present and discuss ideas and innovations in the design, definition, analysis, implementation and practical use of programming languages. SBLP's first edition was in 1996. Since 2010, it is part of CBSoft, the Brazilian Conference on Software: Theory and Practice (http://cbsoft.org/cbsoft2018/) *Submission Guidelines* ________________________________________________________________________________ Papers must be original and not simultaneously submitted to another journal or conference. Papers must be submitted electronically (in PDF format) via the Easychair System: http://www.easychair.org/conferences/?conf=sblp2018. The following paper categories are welcome (page limits include figures, references, and appendices): Full papers: up to 8 pages long in ACM 2-column format, available at http://www.acm.org/publications/article-templates/proceedings-template.html Short papers: up to 3 pages in the same format, can discuss new ideas which are at an early stage of development or can report partial results of on-going dissertations or theses. *List of Topics* (related but not limited to the following) ________________________________________________________________________________ • Programming paradigms and styles, scripting and domain-specific languages and support for real-time, service-oriented, multi-threaded, parallel, and distributed programming • Program generation and transformation • Formal semantics and theoretical foundations: denotational, operational, algebraic and categorical • Program analysis and verification, type systems, static analysis and abstract interpretation • Programming language design and implementation, programming language environments, compilation and interpretation techniques *Program Committee* ________________________________________________________________________________ Mariza Bigonha Universidade Federal de Minas Gerais Roberto Bigonha Universidade Federal de Minas Gerais Andre R. Du Bois Universidade Federal de Pelotas Christiano Braga Universidade Federal Fluminense Carlos Camarão Universidade Federal de Minas Gerais (chair) Fernando Castor Universidade Federal de Pernambuco Renato Cerqueira IBM Research, Brazil Joao Ferreira Teesside University Lucília Figueiredo Universidade Federal de Ouro Preto Ismael Figueroa Pontifícia Universidad Católica de Valparaiso Alex Garcia Instituto Militar de Engenharia Roberto Ierusalimschy Pontifícia Universidade Católica do Rio de Janeiro Yu David Liu State University of New York at Binghamton Hans-Wolfgang Loidl Heriot-Watt University Marcelo Maia Universidade Federal de Uberlândia André M. Maidl Pontifícia Universidade Católica do Paraná Manuel A. Martins Universidade de Aveiro Sérgio Medeiros Universidade Federal do Rio Grande do Norte Victor Miraldo University of Utrecht Álvaro Moreira Universidade Federal do Rio Grande do Sul Anamaria M. Moreira Universidade Federal do Rio de Janeiro Peter Mosses Swansea University Martin Musicante Universidade Federal do Rio Grande do Norte Alberto Pardo Universidad de la República Fernando Pereira Universidade Federal de Minas Gerais Gustavo Pinto Universidade Federal do Pará Louis-Noel Pouchet Ohio State University Zongyan Qiu Peking University Leonardo Reis Universidade Federal de Ouro Preto Rodrigo Ribeiro Universidade Federal de Ouro Preto Noemi Rodriguez Pontifícia Universidade Católica do Rio de Janeiro Francisco Sant'Anna Universidade Estadual do Rio de Janeiro João Saraiva Universidade do Minho Martin Sulzmann Hochschule Karlsruhe - Technik und Wirtschaft (chair) Leopoldo Teixeira Universidade Federal de Pernambuco Varmo Vene University of Tartu *Invited Speaker* ________________________________________________________________________________ Martin Sulzmann, Hochschule Karlsruhe - Technik und Wirtschaft, Germany *Publication* ________________________________________________________________________________ As in previous editions, after the conference authors of selected regular papers will be invited to submit an extended version of their work to be considered for publication in a journal's special issue. Since 2009, selected papers of each SBLP edition are being published in a special issue of Science of Computer Programming, by Elsevier. *Important dates* ________________________________________________________________________________ Abstract submission: April 29th 2018 Paper submission: May 6th 2018 Author notification: June 22nd 2018 Camera ready deadline: July 8th 2018 *Contact* ________________________________________________________________________________ All questions about submissions should be emailed to Carlos Camarão (camarao(a)dcc.ufmg.br)

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ANNOUNCE: servant-pandoc 0.5.0.0
by Ivan Lazar Miljenovic 16 Jan '18

16 Jan '18

I'm pleased to announce the latest release of the servant-pandoc library: https://hackage.haskell.org/package/servant-pandoc-0.5.0.0 servant-pandoc allows you to take the documentation created with servant-docs and use Pandoc to convert it into whichever format you want (rather than the Markdown generated by servant-docs). The main changes in this release are to provide compatibility with servant-docs-0.11.1; specifically, servant-pandoc now emits all the information that servant-docs does with the same configuration options. As such, there are behavioural changes which necessitated the major version bump. -- Ivan Lazar Miljenovic Ivan.Miljenovic(a)gmail.com http://IvanMiljenovic.wordpress.com

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Haskell port to google fuchsia
by joe skinner 06 Jan '18

06 Jan '18

Hi I have been having a play with this new os and was wondering if there was any work being done on a port of Haskell to this platform. Thanks Joe

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PSA: `cabal update` command needs manual unsticking
by Gershom B 04 Jan '18

04 Jan '18

Dear Haskellers, A recent update to hackage, which fixed up the 01-index.tar.gz file, revealed a bug in existing versions of cabal-install, when index files are cleaned up. This bug means that the `cabal update` command, which updates the hackage index file, will fail silently and leave the old file in place. It is easy to get things working again, but it requires manual intervention. Here is the most straightforward way to get things working again: On gnu/linux or mac: rm ~/.cabal/packages/hackage.haskell.org/01-index.* On windows: remove the same files, but from %appdata%\cabal\packages\hackage.haskell.org rerun `cabal update` to fetch a new 01-index. Apologies all for the inconvenience and any confusion this may have caused. There is a PR to fix this behavior in the works, but since the problem is on the client side, the fix will only improve the situations for new versions of `cabal`. Happy New Years to all, and cheers to a very functional 2018, Gershom p.s.: since the problem comes in unpacking the 01-index.tar.gz into the 01-index.tar, you can also just untar that file in place manually, or force cabal into doing the same by running `touch ~/.cabal/packages/hackage.haskell.org/01-index.tar`

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