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[ghc-steering-committee] The GHC Committee welcomes its new members
by Joachim Breitner 24 Jan '20

24 Jan '20

Dear Haskell community, the GHC Steering committee welcomes three new members, Alejandro Serrano Mena, Cale Gibbard and Tom Harding. We are happy to see that there is continued interest in our work, and are looking forward to having fresh insights and energy on the committee. They take the seat of Sandy Maguire, who we thank for this productive work during his tenure. As you might notice, we picked more candidates than we filled slots. This is not because Sandy’s productivity need three people to fill. The idea is that there is no reason to turn away a motivated contributor just to stick to the arbitrary 10 members. Instead, we will aim at “roughly 10”, and probably not call for new members until we have dropped below that number again. On behalf of the committee, Joachim Breitner PS: Alejandro, Cale and Tom, please send me your github handles and subscribe to the mailing list at https://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-steering-committee -- Joachim “nomeata” Breitner mail(a)joachim-breitner.de https://www.joachim-breitner.de/

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Taking over double-conversion on Hackage
by Rinat Stryungis 21 Jan '20

21 Jan '20

Hi everyone, The double-conversion package seems unmaintained. I'd like to take over as maintainer. I have actually forked the repository, added new functionality, tests, and updated the original Google library: https://github.com/haskell-mouse/double-conversion I was advised to consider taking over the maintenance of double-conversion. I tried to contact Bryan O'Sullivan (the maintainer) a few times during the 2 years (!) using all available communication methods (e-mail, LinkedIn). He answered only once and asked me to send an e-mail. I did it but without any effect. I would still prefer not to have this responsibility, but I would also like people to be able to use the new functionality without creating redundant forks.

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a sort of chunk
by PICCA Frederic-Emmanuel 21 Jan '20

21 Jan '20

Hello, I need to write some code in order to do some computations with stack of images coming from hdf5 files. Each computation done per images is quite intensive, so I want to do this on multiple cores of my computer (24 in my case) A stack of images is composed of a list of files. each file contain n images. So I decided to proceed like this: create a data type which represent a chunk of this stack. data Chunk = Chunk { filename :: FilePath , from :: Int , to :: Int } And indeed the full stack is [Chunk] Now since I have n core, I need to split the full stack in equivalent chunk of images. Just for example. at the begining I have this image stack 30476 images [Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00077.nxs" 0 698,Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00078.nxs" 0 1104,Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00079.nxs" 0 1510,Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00080.nxs" 0 1914,Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00081.nxs" 0 2318,Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00082.nxs" 0 2720,Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00083.nxs" 0 2169,Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00084.nxs" 0 2445,Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00085.nxs" 0 2720,Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00086.nxs" 0 490,Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00087.nxs" 0 812,Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00088.nxs" 0 1133,Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00089.nxs" 0 1454,Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00090.nxs" 0 1773,Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00091.nxs" 0 2090,Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00092.nxs" 0 2406,Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00093.nxs" 0 2720] so i need to write a function which do something like chunksOf chunksOf :: Int -> [Chunk] -> [[Chunk]] In this case I need to create chunk of 1325 images, so the finla result should be [ [Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00077.nxs" 0 698,Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00078.nxs" 0 627] , [Chunk "/nfs/ruche-sixs/sixs-soleil/com-sixs/2019/Run3/FeSCO_Cu111/sample2_ascan_omega_00078.nxs" 627 1104, ...] ... ] I would like your help in order to give me advices or help me find information whcih can help me implement this chunksOf method. thanks for your help. Frederic

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10 PhD studentships in Nottingham for Home/EU applicants
by Graham Hutton 20 Jan '20

20 Jan '20

Dear all, The School of Computer Science at the University of Nottingham is seeking applications for 10 fully-funded PhD studentships for Home/EU students: https://tinyurl.com/ten-phds-2020 Applicants in the area of the Functional Programming Laboratory (https://tinyurl.com/fp-notts) are strongly encouraged! If you are interested in applying, please contact a potential supervisor as soon as possible (the application deadline is 6th March): Thorsten Altenkirch - constructive logic, proof assistants, homotopy type theory, category theory, lambda calculus. Venanzio Capretta - type theory, mathematical logic, corecursive structures, proof assistants, category theory, epistemic logic. Graham Hutton - not taking on any new students this year, but you may find these notes useful: https://tinyurl.com/scbkxkr Henrik Nilsson - functional reactive programming, domain- specific languages, generalised notions of computation. These positions are only open to Home/EU applicants. An advert for international students was posted earlier and is now closed. Best wishes, Graham +-----------------------------------------------------------+ 10 Fully-Funded International PhD Studentships School of Computer Science University of Nottingham, UK https://tinyurl.com/ten-phds-2020 Applications are invited for 10 fully-funded PhD studentships for Home/EU students in the School of Computer Science at the University of Nottingham, starting on 1st October 2020. The topics for the studentships are open, but should relate to the interests of one of the School’s research groups: Agents Lab; Computational Optimisation and Learning Lab; Computer Vision Lab; Functional Programming; Intelligent Modelling and Analysis; Mixed Reality Lab; Data Driven Algorithms, Systems and Design and Uncertainty in Data and Decision Making The studentships are for three and a half years and include a stipend of £15,009 per year and tuition fees. Applicants are normally expected to have a first-class Masters or Bachelors degree in Computer Science or a related discipline, and must obtain the support of a potential supervisor in the School prior to submitting their application. Initial contact with supervisors should be made at least two weeks prior to the closing date for applications. Eligible successful applicants are expected to apply for a EU VC Scholarship. Informal enquiries may be addressed to Kathleen.Fennemore(a)nottingham.ac.uk. To apply, please submit the following items by email to: Marc.Williams(a)nottingham.ac.uk: (1) a copy of your CV, including your actual or expected degree class(es), and results of all University examinations; (2) an example of your technical writing, such as a project report or dissertation; (3) contact details for two academic referees. (4) a research proposal – max 2 x sides A4 You may also include a covering letter but this is optional. Closing date for applications: Friday 6 March 2020. +-----------------------------------------------------------+ 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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Haskell.org Committee Nomination Results
by Emily Pillmore 20 Jan '20

20 Jan '20

Hello Everyone, I'm pleased to announce that the results for the Haskell.org ( http://haskell.org/ ) committee nominations are in, and voting has completed. The following tally is the final result: Jaspe Van der Jeugt: 6 Alexandre Garcia de Oliveira: 5 April Gonçalves: 2 Rebecca Skinner: 5 With no votes for anyone else. This means that Jasper's renomination was successful, and we get to welcome 2 new faces to the Haskell.org ( http://haskell.org/ ) ; congratulations Rebecca and Alexandre! Thanks, Emily

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persistent and safe-money packages
by Debasish Ghosh 17 Jan '20

17 Jan '20

Hi - I am using "persistent" for database access in Haskell. However in my domain model I have used the Dense data type from safe-money ( https://hackage.haskell.org/package/safe-money) as the money datatype. It looks like this data type is not supported by default in persistent. Is there a way around ? Thanks in advance. -- Debasish Ghosh http://manning.com/ghosh2 http://manning.com/ghosh Twttr: @debasishg Blog: http://debasishg.blogspot.com Code: http://github.com/debasishg

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[ANN] 2nd Call for Participation: BOB 2020 (February 28, Berlin, early-bird until Jan 20)
by Stefan Wehr 15 Jan '20

15 Jan '20

================================================================================ BOB 2020 Conference “What happens if we simply use what’s best?” February 28, 2020, Berlin http://bobkonf.de/2020/ Program: http://bobkonf.de/2020/en/program.html Registration: http://bobkonf.de/2020/en/registration.html ================================================================================ BOB is the conference for developers, architects and decision-makers to explore technologies beyond the mainstream in software development, and to find the best tools available to software developers today. Our goal is for all participants of BOB to return home with new insights that enable them to improve their own software development experiences. The program features 14 talks and 8 tutorials on current topics: http://bobkonf.de/2020/en/program.html The subject range of talks includes functional programming, formal methods, architecture documentation, functional-reactive programming, and language design. The tutorials feature introductions to Idris, Haskell, F#, TLA+, ReasonML, and probabilistic programming. Heather Miller will give the keynote talk. Registration is open online: http://bobkonf.de/2020/en/registration.html NOTE: The early-bird rates expire on January 20, 2020! BOB cooperates with the Racketfest conference on the day before BOB: https://racketfest.com/ BOB cooperates with the :clojureD conference on the day after BOB: https://clojured.de/

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[Job] Hiring Numerical Programmers at Anduril Industries
by Travis Whitaker 15 Jan '20

15 Jan '20

Greetings Fellow Haskellers, Anduril Industries is hiring Haskellers for numerical programming work. Quick Details: - Seeking Haskellers familiar with numerical programming techniques. - Familiarity with LLVM, FORTRAN, Linux, and compiler engineering is advantageous. - Positions for internships and new graduates are available. - Regrettably, no remote opportunities are available at this time. We are located in southern California, USA. Anduril is looking for engineers to rapidly develop high-reliability solutions to numerical problems by leveraging lightweight formal methods. We are working on problems from a wide range of disciplines, including robotics, flight control, guidance & navigation, and radar signal processing. If you're interested in numerical programming, physics, and lightweight formal verification techniques, then you'd likely enjoy working on our team! With respect to internships, our program is extremely flexible and we can adapt to whatever structure your university might require. If this sounds interesting, please drop me a line at travis(a)anduril.com. Thanks for your time, Travis Whitaker

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database programming with Haskell
by Debasish Ghosh 15 Jan '20

15 Jan '20

Hello - I am looking for some good practices on how to design database access APIs in applications using Haskell. I have been going through various libraries like persistent, Esqueleto etc. All of them have nice APIs. However I am looking for practices around designing APIs that also offer testability without plugging in a concrete database engine. Like the one we can design using tagless final approaches where we can switch out the Database monad with some mocked one (maybe that uses some hashmap instead of a real database) for unit tests. Is there any recommended practice on this or may be some sample application that's designed around these practices ? Or is this at all a recommended practice in Haskell ? regards. -- Debasish Ghosh http://manning.com/ghosh2 http://manning.com/ghosh Twttr: @debasishg Blog: http://debasishg.blogspot.com Code: http://github.com/debasishg

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[TFP'20] call for participation: Trends in Functional Programming 2020, 13-14 February, Krakow, Poland
by Peter Achten 14 Jan '20

14 Jan '20

------------------------------------------------------------------------- Call for participation 21st Symposium on Trends in Functional Programming tfp2020.org ------------------------------------------------------------------------- The list of accepted papers is available at http://www.cse.chalmers.se/~rjmh/tfp/ The symposium on Trends in Functional Programming (TFP) is an international forum for researchers with interests in all aspects of functional programming, taking a broad view of current and future trends in the area. It aspires to be a lively environment for presenting the latest research results, and other contributions. * TFP is moving to new winter dates, to provide an FP forum in between the annual ICFP events. * TFP offers a supportive reviewing process designed to help less experienced authors succeed, with two rounds of review, both before and after the symposium itself. Authors have an opportunity to address reviewers' concerns before final decisions on publication in the proceedings. * TFP offers two "best paper" awards, the John McCarthy award for best paper, and the David Turner award for best student paper. * This year we are particularly excited to co-locate with Lambda Days in beautiful Krakow. Lambda Days is a vibrant developer conference with hundreds of attendees and a lively programme of talks on functional programming in practice. TFP will be held in the same venue, and participants will be able to session-hop between the two events. Important Dates --------------- Submission deadline for pre-symposium review: 15th November, 2019 -- passed -- Submission deadline for draft papers: 10th January, 2020 -- passed -- Registration (regular): 2nd February, 2020 Registration (late): 13th February, 2020 Symposium dates: 13-14th February, 2020 Visit tfp2020.org for more information.

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