Haskell Weekly


Issue 175 2019-09-05

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Welcome to another issue of Haskell Weekly! Haskell is a safe, purely functional programming language with a fast, concurrent runtime. This is a weekly summary of what’s going on in its community.


  • Announcing the optics library by Adam Gundry

    We are delighted to announce the first Hackage release of optics, a Haskell library for defining and using lenses, traversals, prisms and other optic kinds.

  • GSoC: The Conclusion by Vijay Tadikamalla

    Finally, it’s time to wrap up and finalize the project. Here is my GSoC project HsYAML. Undoubtedly, it was the best summer.

  • GSoC-2019 by Kostas Dermentzis

    In my gsoc-2019 project, I used quickcheck-state-machine to write tests about different dbs, with the aim to test new functionality that I added to these dbs, provide good examples of how to write tests using q-s-m, and also improve q-s-m itself.

  • The ZuriHac registration system by Jasper Van der Jeugt

    I am one of the organizers of ZuriHac, and last year, we hand-rolled our own registration system for the event in Haskell.

  • Dynamic typing by Type Classes

    Haskell has a type called Dynamic which resembles a dynamically-typed variable in some other languages.

  • Haskell Disappointment by Nicolas Rinaudo

    I was recently asked to explain why I felt disappointed by Haskell, as a language. And, well. Crucified for crucified, I might as well criticise Haskell publicly.

  • How GHC 8.8 nearly killed singletons by Ryan Scott

    What the changelog doesn’t contain is a story about how the singletons library nearly perished due to changes introduced in GHC 8.8.

  • Bypassing MAX_PATH Limit with GHC on Windows by Tamar Christina

    GHC 8.10+ Will ship with a custom GCC+Binutils bindist that will remove the MAX_PATH limitation to files.

  • Simulating network failures at syscall level by Tomasz Guz

    The goal was to check high-level fault-tolerance property while sending messages to Kafka and I ended up changing the CPU register to get the exact failure I wanted and exactly when I wanted.

  • Relational Algebra with Fancy Types by Philip Zucker

    Last time, I tried to give a primer of relations and relational algebra using the Haskell type type Rel a b = [(a,b)]. In this post we’re going to look at these ideas from a slightly different angle.


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In brief

Package of the week

This week’s package of the week is optics, a library that makes it possible to define and use Lenses, Traversals, Prisms and other optics, using an abstract interface.

Call for participation