Welcome to issue 102 of HWN, a newsletter covering developments in the Haskell community.

Announcements

Monoids and fingertrees. Heinrich Apfelmus posted a nice tutorial explaining the monoid magic behind 2-3 fingertrees.

STM-IO-Hooks-0.0.1. Peter Robinson announced the stm-io-hooks library, which provides an STM monad with commit and retry IO hooks. A retry-action is run (once) in a separate thread if the transaction retries, while commit-actions are executed iff the transaction commits. The code is based on the AdvSTM monad by Chris Kuklewicz, but in addition also ensures some atomicity guarantees for commit-actions.

1000 libraries. Don Stewart announced that Hackage has now reached 1000 packages!

HTTP-4000.0.4 released. Sigbjorn Finne announced that a new release of HTTP, version 4000.0.4, is now available. The main change is the addition of registering a Browser event handler for capturing state changes to the request-response processing pipeline.

Blog noise

Haskell news from the blogosphere.

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/ .