Welcome to issue 124 of HWN, a newsletter covering developments in the Haskell community.


HLint 1.6. Neil Mitchell announced the release of HLint 1.6, a tool for automatically suggesting improvements to Haskell code.

Haskell Implementers Workshop: accepted talks. Simon Marlow announced that the list of talks at the Haskell Implementers Workshop 2009 has now been posted.

bloxorz clone. Patai Gergely announced a Haskell clone of the game "bloxorz", written by Viktor Devecseri.

Fun with type functions. Simon Peyton-Jones announced that he, Ken Shan, and Oleg have finished Version 2 of their paper "Fun with Type Functions", which gives a programmer's tour of what type functions are and how they are useful. If you have a moment to look at, and wanted to help them improve it, leave comments on the linked wiki page.

package Boolean: Generalized booleans. Conal Elliott announced Boolean, a new package for generalized booleans, which provides type classes with generalizations of Boolean values and operations, if-then-else, Eq and Ord.

TernaryTrees- - An efficient ternary tree implementation of Sets and Maps. Alex Mason announced the release of TernaryTrees, a package that extends Data.Set ad Data.Map with some ternary tree structures, one of the more efficient ways of storing strings in a set.

6.12.1 planning. Simon Marlow announced plans for a release of GHC 6.12.1, sometime around September. If you have the time and inclination to help with any of the listed features, please get involved!

regular-0.1. José Pedro Magalhães announced the release of the regular library. Many generic programs require information about the recursive positions of a data type, such as generic fold, generic rewriting, and the Zipper data structure. Regular provides a fixed point view on data which allows these definitions for regular data types. It also serves as the basis for a generic rewriting library.

Google Summer of Code

Progress updates from participants in the 2008 Google Summer of Code.

Haddock improvements. Isaac Dupree has made it easier to generate Haddock documentation for non-exported functions, posted an overview of the issues involved in getting proper cross-package documentation working, and his current plan.

EclipseFP. Thomas Ten Cate has done a lot of work on EclipseFP, including some cosmetic updates and getting error reporting to work better.

space profiling. Gergely Patai is working on a network protocol for his profiling grapher tool, so that other tools can monitor the profiling information.

haskell-src-exts. Niklas Broberg has released haskell-src-exts version 1.0.0!

fast darcs. Petr Rockai has completed quite a bit of work on darcs, including a beta release of darcs 2.3.


Monoid wants a (++) equivalent. Bryan O'Sullivan suggested adding a more concise operator to the Monoid class for 'mappend', leading to a long, bike-shed-ish (but hopefully still useful) discussion.

Reflections on the ICFP 2009 programming contest. Justin Bailey began a discussion on results and experiences from the ICFP 2009 programming contest.

Blog noise

Haskell news from the blogosphere. Blog posts from people new to the Haskell community are marked with >>>, be sure to welcome them!

Quotes of the Week

About the Haskell Weekly News

New editions are posted to the Haskell mailing list as well as to the Haskell Sequence and Planet Haskell. RSS is also available, and headlines appear on haskell.org.

To help create new editions of this newsletter, please see the information on how to contribute. Send stories to byorgey at cis dot upenn dot edu. The darcs repository is available at darcs get http://code.haskell.org/~byorgey/code/hwn/ .