December 2019 - Haskell-Cafe

stack: pandoc fails to build as dependency
by Olaf Klinke 06 Aug '20

06 Aug '20

Dear cafe, I am baffled to learn that stack does not provide builds as reproducible as advertised. I have a project that depends on pandoc. It builds fine on my Debian 9 machine. Then I check out the project on a Debian 8 machine. Downloading and building pandoc-2.7.3 with the latest stack-2.1.3 on the Debian 8 machine runs fine. Now I create a new project, using the same stack.yaml as in the pandoc-2.7.3 package, except now pandoc-2.7.3 is an extra-dep. The project's only module contains nothing but: module Test where import Text.Pandoc Building this project with the same stack results in a linker error: pandoc > Preprocessing executable 'pandoc' for pandoc-2.7.3.. pandoc > Building executable 'pandoc' for pandoc-2.7.3.. pandoc > [1 of 2] Compiling Main pandoc > [2 of 2] Compiling Paths_pandoc pandoc > Linking .stack-work/dist/x86_64-linux/Cabal-2.4.0.1/build/pandoc/pandoc ... pandoc > collect2: error: ld returned 1 exit status pandoc > `gcc' failed in phase `Linker'. (Exit code: 1) This seems to be independent of the LTS version (the stack.yaml in pandoc-2.7.3 says lts-13.17 although lts-13.17 contains pandoc-2.5 and pandoc-2.7.3 is available only in 14.9). Can somebody hint what I am doing wrong? Should I file a bug report? Thanks Olaf

3 3

Supporting Haskell.org
by Tikhon Jelvis 06 Jan '20

06 Jan '20

A significant part of the Haskell community infrastructure—including the haskell.org website, Hackage, Hoogle and the build infrastructure for GHC—runs on donations from the Haskell community administered by Haskell.org. Haskell.org also organizes Haskell's participation in the Google Summer of Code program. We had 18 projects this year, 15 of which were completed successfully, a solid completion ratio. If you would like to support Haskell.org, you can donate via several methods including PayPal and check: https://wiki.haskell.org/Donate_to_Haskell.org Haskell.org can also accept donations through employers via Benevity using the unique ID 475236502. Haskell.org is a 501(c)(3) non-profit, so donations may be tax-deductible in your jurisdiction. We look forward to continuing this work with your support in 2020 as well as exploring new projects to improve the Haskell community infrastructure. Best wishes, Tikhon Jelvis on behalf of the haskell.org committee.

2 1

SBLP 2020 - first call for papers
by Simon Thompson 31 Dec '19

31 Dec '19

Call for Papers - XXIV Brazilian Symposium on Programming Languages (SBLP 2020) Natal, Brazil, September 21-25, 2020 Submission link: https://easychair.org/conferences/?conf=sblp2020 SBLP 2020 is the 24th 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. Submission Guidelines ________________________________________________________________________________ Papers can be written in Portuguese or English. Submissions in English are encouraged because the proceedings will be indexed in the ACM Digital Library. The acceptance of a paper implies that at least one of its authors will register for the symposium to present it. Papers must be original and not simultaneously submitted to another journal or conference. SBLP 2020 will use a lightweight double-blind review process. The manuscripts should be submitted for review anonymously (i.e., without listing the author’s names on the paper) and references to own work should be made in third person. Papers must be submitted electronically (in PDF format) via the Easychair System: http://www.easychair.org/conferences/?conf=sblp2020 The following paper categories are welcome (page limits include figures, references and appendices): Full papers: up to 8 pages long in ACM 2-column conference format, available at http://www.acm.org/publications/proceedings-template Short papers: up to 3 pages in the same format. Short papers 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 Publication ________________________________________________________________________________ SBLP proceedings will be published in ACM's digital library. As in previous editions, 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: 31 May, 2020 Paper submission: 7 June, 2020 (strict) Author notification: 24 July, 2020 Camera ready deadline: 9 August 2020 Program Committee ________________________________________________________________________________ Alex Garcia Instituto Militar de Engenharia Alvaro Moreira Universidade Federal do Rio Grande do Sul Anamaria Moreira Universidade Federal do Rio de Janeiro André Murbach Maidl Pontifícia Universidade Católica do Paraná Bernhard Scholz The University of Sydney Beta Ziliani Universidad Nacional de Córdoba Christiano Braga Universidade Federal Fluminense Cristiano Vasconcellos Universidade do Estado de Santa Catarina Fernando Castor Universidade Federal de Pernambuco Fernando Pereira Universidade Federal de Minas Gerais Francisco Sant'Anna Unversidade Estadual do Rio de Janeiro Hans-Wolfgang Loidl Heriot-Watt University Henrique Rebêlo Universidade Federal de Pernambuco João Paulo Fernandes University of Coimbra Krishna Nandivada IIT Madras Laure Gonnord University of Lyon Leonardo Reis Universidade Federal de Juiz de Fora Lucilia Figueiredo Universidade Federal de Ouro Preto Marisa Bigonha Universidade Federal de Minas Gerais Martin Musicante Universidade Federal do Rio Grande do Norte Pavlos Petoumenos University of Manchester Renato Cerqueira IBM Research Roberto Ierusalimschy PUC-Rio Rodrigo Ribeiro Universidade Federal de Ouro Preto Sandro Rigo Universidade de Campinas Sérgio Medeiros Universidade Federal do Rio Grande do Norte (Chair) Simon Thompson University of Kent Tomofumi Yuki INRIA Contact ________________________________________________________________________________ All questions about submissions should be emailed to Sérgio Medeiros (sergiomedeiros(a)ect.ufrn.br) Simon Thompson | Professor of Logic and Computation School of Computing | University of Kent | Canterbury, CT2 7NF, UK s.j.thompson(a)kent.ac.uk | M +44 7986 085754 | W www.cs.kent.ac.uk/~sjt

1 0

A Generic Ordering over Types
by Justin Paston-Cooper 29 Dec '19

29 Dec '19

Hello, I've defined a module which defines a Data.Type.Ordering over types which are instances of Generic: https://github.com/jpcooper/generic-type-ordering/blob/master/src/Data/Type…. I was considering submitting it to Hackage if anyone finds this useful. I am using it in conjunction with Data.Type.Set (type-level-sets), which requires an ordering over the used types. The ordering works by first comparing the package, then the module, then the type name. I take it that the ordering as defined is correct over all types which are an instance of Generic. I wanted to check first whether this is done anywhere else, or in a different, better way. Can anyone advise? Cheers, Justin

3 5

Re: [Haskell-cafe] Which is easier to ship on windows, a gi-gtk or fltk-hs project?
by Ruben Astudillo 25 Dec '19

25 Dec '19

On 25-12-19 02:13, Patrick Chilton wrote: > Hi, maybe you could host it somewhere and give it a web interface? > Google Compute Engine has a pretty generous free tier and you can > install Nix on it, which would take care of the packaging issues. I would prefer to not. Conceptually that is a harder sell as there is not a good technical reason to depend on webstuff apart of inconvenience. Also TeX compilation should be done on a web service if it's on the web (I think). This is a side project, which for me it's a opportunity to learn something new. That is right now shipping programs to windows that use bindings and depend on other programs. -- -- Rubén -- pgp: 4EE9 28F7 932E F4AD

1 0

Which is easier to ship on windows, a gi-gtk or fltk-hs project?
by Ruben Astudillo 25 Dec '19

25 Dec '19

Dear list Currently for work I am doing a technical document generator using HaTex. The user primarily uses windows so I would like to ship to it. He is not a technical user, so a GUI is a must. FLTK is lighter than gtk but it seems the community has less experience shipping haskell GUIs with it on windows than with gi-gtk. So which toolkit binding would you use for a windows project? Also how would you ship such a project, which depends on a toolkit and TeX-engine on windows? I am used to a nix world-view. -- -- Rubén -- pgp: 4EE9 28F7 932E F4AD

1 0

[ANN] ascii-holidays
by amindfv＠gmail.com 24 Dec '19

24 Dec '19

For those of you celebrating Christmas this week, I've just uploaded an early version of the ascii-holidays package to Hackage. At the moment it's a reimplementation of two ASCII art Christmas tree animations, one originally written in Bash and the other in Perl. Over time I plan to add animations for other holidays as well. You can install it with cabal install, then run it like: ascii-holidays xmas-1 I hope this adds a bit of Haskelly Christmas cheer to a few homes, and happy holidays to all! Tom

3 3

Records, type-changing update, type inference
by Roman 21 Dec '19

21 Dec '19

I wrote a post about the records problem, in particular about type-changing update and how to get it without sacrificing type inference: https://github.com/effectfully/sketches/tree/master/has-lens-done-right The ideas are rather raw, but look promising to me. Any comments would be appreciated.

1 0

PhD and Postdoc positions at IMDEA
by Niki Vazou 21 Dec '19

21 Dec '19

Dear all, IMDEA Software Institute has open PhD and Postdoc positions. The selected candidate will work on liquid relational types and the application deadline is February 1st: https://software.imdea.org/open_positions.html Feel free to contact me for more information. Best, Niki

1 0

Third call for draft papers for TFPIE 2020 (Trends in Functional Programming in Education)
by Jurriaan Hage 20 Dec '19

20 Dec '19

Hello, Please, find below the third call for draft papers for TFPIE 2020. Please forward these to anyone you think may be interested. Apologies for any duplicates you may receive. best regards, Jurriaan Hage Chair of TFPIE 2020 ======================================================================== TFPIE 2020 Call for papers http://www.staff.science.uu.nl/~hage0101/tfpie2020/index.html February 12th 2020, Krakow, Poland (co-located with TFP 2020 and Lambda Days) *NEW* Invited Speaker We are happy to announce the invited speaker for TFPIE 2020, Thorsten Altenkirch, who also speaks at Lambda Days. At TFPIE 2020 he shall be talking about his new book, Conceptual Programming With Python. *NEW* Registration This year TFPIE takes place outside of the Lambda Days/TFP organisation, although it takes place near their location. This means you do need to register separately for TFPIE; it also means you can register for TFPIE without registering for TFP/LambdaDays, and vice versa. Registration is mandatory for at least one author of every paper that is presented at the workshop. Only papers that have been presented at TFPIE may be submitted to the post-reviewing process. Registration is 25 euro per person. TFPIE 2020 welcomes submissions describing techniques used in the classroom, tools used in and/or developed for the classroom and any creative use of functional programming (FP) to aid education in or outside Computer Science. Topics of interest include, but are not limited to: FP and beginning CS students FP and Computational Thinking FP and Artificial Intelligence FP in Robotics FP and Music Advanced FP for undergraduates FP in graduate education Engaging students in research using FP FP in Programming Languages FP in the high school curriculum FP as a stepping stone to other CS topics FP and Philosophy The pedagogy of teaching FP FP and e-learning: MOOCs, automated assessment etc. Best Lectures - more details below In addition to papers, we are requesting best lecture presentations. What's your best lecture topic in an FP related course? Do you have a fun way to present FP concepts to novices or perhaps an especially interesting presentation of a difficult topic? In either case, please consider sharing it. Best lecture topics will be selected for presentation based on a short abstract describing the lecture and its interest to TFPIE attendees. The length of the presentation should be comparable to that of a paper. On top of the lecture itself, the presentation can also provide commentary on the lecture. Submissions Potential presenters are invited to submit an extended abstract (4-6 pages) or a draft paper (up to 20 pages) in EPTCS style. The authors of accepted presentations will have their preprints and their slides made available on the workshop's website. Papers and abstracts can be submitted via easychair at the following link: https://easychair.org/conferences/?conf=tfpie2020 . After the workshop, presenters will be invited to submit (a revised version of) their article for review. The PC will select the best articles that will be published in the Electronic Proceedings in Theoretical Computer Science (EPTCS). Articles rejected for presentation and extended abstracts will not be formally reviewed by the PC. Dates Submission deadline: January 14th 2020, Anywhere on Earth. Notification: January 17th 2020 TFPIE Registration Deadline: January 20th 2020 Workshop: February 12th 2020 Submission for formal review: April 19th 2020, Anywhere on Earth. Notification of full article: June 6th 2020 Camera ready: July 1st 2020 Program Committee Olaf Chitil - University of Kent Youyou Cong - Tokyo Institute of Technology Marko van Eekelen - Open University of the Netherlands and Radboud University Nijmegen Jurriaan Hage (Chair) - Utrecht University Marco T. Morazan - Seton Hall University, USA Sharon Tuttle - Humboldt State University, USA Janis Voigtlaender - University of Duisburg-Essen Viktoria Zsok - Eotvos Lorand University Note: information on TFP is available at http://www.cse.chalmers.se/~rjmh/tfp/

1 0