Haskell

Andres and Wouter interview Edwin Brady, most famous for his work on the Idris programming language. We talk about how he got interested in programming with dependent types, his thoughts on dependently typed programming in Haskell, and his vision for Idris.

News about the Haskell programming language from 2023-11-30.

Anyone want to guess how many errors this code generates:

{-# LANGUAGE DerivingVia #-}

module T where

newtype OrdList1 a = OrdList1 [a]
  deriving (Functor, Foldable, Traversable) via []

newtype OrdList2 a = OrdList2 [a]
  deriving (Functor, Foldable, Traversable) via Maybe

#haskell

Lennart Augustsson gave a talk in the FP seminars at Chalmers, Gothenburg, about his new MicroHaskell.

Abstract:

MicroHs is an implementation of a subset Haskell that is using combinators;
pretty much as described in David Turner's 1979 paper A New Implementation Technique for Applicative Languages.
The implementation has very few dependencies, and the binaries can run on almost anything that has a C compiler.
The talk will illustrate a few aspects of compiling to combinators.

I have started the process where the GHC Steering Committee decides if we should have a GHC2024 language edition, and what it should contain. @MangoIV rightfully reminded me that when we laid out the process three years ago, we said we’d hold a community poll as well.

So here we go...

Adds a linear fat arrow %1 => this is meant to greatly improve the ergonomics of some of the APIs using linear types (it tends to apply to APIs based on typestate or related to mutation).

Rendered

Hate watching videos? Check out the complementary article, which covers the same content: https://dev.to/zelenya/how-to-introduce-haskell-into-your-company-9ff

News about the Haskell programming language from 2023-11-16.

Joachim Breitner and David Christiansen interview John MacFarlane, a professor of philosophy at UC Berkeley, but also the author of the popular pandoc document conversion tool, which has been around half as long as Haskell itself. He also explains the principle of uniformity as a design goal for lightweight markup languages, the relationship between philosophy and programming, and along the way he helps David with his markdown difficulties.

Hi everyone, The Cabal development community is sending a call for participation in our quality assurance (QA) programme. We are looking to improve the quality of the software we ship on the Windows platform.

The GHC developers are happy to announce the availability of GHC 9.4.8. Binary distributions, source distributions, and documentation are available on the release page.

This release is primarily a bugfix release addressing a few issues
found in the 9.4 series. These include:

• A fix for a recompilation checking bug where GHC may miss changes in transitive dependencies when deciding to relink a program (#23724).
• A fix for a code generator bug on AArch64 platforms resulting in invalid conditional jumps (#23746).
• Support for -split-sections on Windows.
• Enabling -split-sections for various Linux and Windows binary distributions, enabling GHC to produce smaller binaries on these platforms.

How to upgrade

ghcup upgrade

If you haven't installed yet, follow the instructions at: https://www.haskell.org/ghcup/

Changelog

New features

• support TUI on windows thanks to the work from vty and brick maintainers (Chris Hackett, Timofey Zakrevskiy, Jonathan Daugherty, ...), wrt #912

  • this may be experimental though

• support JS and wasm cross compilers wrt #838, thanks to Sylvain Henry and IOG

• Support stacks installation strategy and metadata wrt #892

  • you can now enable stacks installation method via ghcup config set url-source '["GHCupURL", "StackSetupURL"]'... for more information, check the documentation

Improvements and bug fixes

• fix segfault in TUI when hitting enter early wrt #887
• Improve key handling in TUI, fixes #875
• add explicit support for Void Linux and Rocky Linux (this required a metadata version bump to ghcup-0.0.8.yaml)
• optparse cli interface now has a test suite thanks to Lei Zhu, wrt #862

News about the Haskell programming language from 2023-11-09.

It is my great pleasure to announce that we have hired a new Executive Director for the Haskell Foundation: José Manuel Calderón Trilla. José is a long-time Haskeller and Haskeller-educator, with a PhD from the University of York, a stint at Galois, and is currently wrapping up a lectureship at the University of Maryland...

Why is there no strict until?

https://gist.github.com/noughtmare/a41f3e822210245d1880d3f397f282aa

#haskell

In this episode, we are going to look at the common design pattern where we abstract all the fields of a record type over a type constructor which can then be instantiated to the identity to get the original record type back, but also to various other interesting type constructors. We are going to look at a few examples, and are also going to see how common operations on such types naturally lead to the use of higher-rank polymorphic types.

The fastest effect system approaches translate operations into a fast concrete monad like IO or State.

https://gist.github.com/noughtmare/cccda38eb7c67c1ea6df6a3377f1da0d

#haskell

The Dutch Functional Programming Day (also known as FP Dag) is an annual gathering of researchers, students, and practitioners sharing a common interest in functional programming.

The day features talks that cover the latest advances in research, teaching and applications in the area of functional programming and (implementation of) functional languages.

The FP Dag will take place on January 5th 2024, at the Technical University of Delft.

Participation is free of charge, however, registration is mandatory. Lunch and breaks will be provided.

News about the Haskell programming language from 2023-11-02.

Preview: I’m happy to announce the release of vty version 6.0. The highlight of this release is that vty now works on Windows, thanks to hard work by Chris Hackett and Timofey Zakrevskiy! For years, many people in the Haskell community have requested Windows support in vty. Thanks to Chris and Timofey for the time and energy they put into this, and their patience as we worked out an approach! Thanks also to Eric Mertens and Kevin Quick for early feedback on the release...