Haskell Weekly


Issue 196 2020-01-30

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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.


  • Haskell Problems For a New Decade by Stephen Diehl

    The problems we work on in the present are those that shape the future, and often the choice of problems is what matters more than anything else.

  • One Haskell IDE to rule them all by Neil Mitchell

    The Haskell IDE Engine and Ghcide teams are joining forces on a single IDE.

  • Policeman in da Bristol city by Kowainik

    There is a need to automate this process and that is why we have created policeman — your versioning guard.

  • Folding lists by Type Classes

    The functions foldr, foldMap, and fold are convenient ways to combine all of the elements of a list.

  • Hpack: A Simpler Package Format by Monday Morning Haskell

    But .cabal files have some weaknesses, as we’ll explore. Luckily, there’s another tool out there called Hpack.

  • Help! My Haskell program consumes more memory the longer it runs by Jacob Stanley

    You look at the offending code and you’re updating a few maps but there doesn’t seem to be anything going on that would use a lot of memory.

  • Case study: migrating from lens to optics by Oleg Grenrus

    Some time ago I commented on Reddit, that there are no real experience reports about migrating “real world Haskell codebases” from lens to optics. So I decided to do an experiment.

  • Property testing in depth: The size parameter by Tom Sydney Kerckhove

    This post explains the size parameter of a property testing generator, and expands on its tradeoffs.

  • vmap in Haskell by Edward Z. Yang

    Semantically, a vmap is exactly equivalent to a map in Haskell; the key difference is that operations run under a vmap are vectorized.

  • Transformations on Applicative Concurrent Computations by Román González

    In this blog post, we will discuss some of the drawbacks of using the Concurrently type when composing sub-routines.


  • Interos is Hiring Full Stack Haskell Software Engineers (ad)

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Trying to hire a Haskell developer? You should advertise with us!

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