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


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

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