Haskell Weekly News: January 24, 2009

Submitted by byorgey on Sat, 01/24/2009 - 10:04am.
Haskell Weekly News: January 24, 2009

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

  • Jonathan Cast: [on advertising for Haskell programmers and informing them that the codebase is actually in Perl at the interview] <Andrew Wagner> That's......evil. <Jonathan> I know. I'm evil too, though. So it's cool.
  • rwbarton: A type class is not a type just like a dog house is not a dog.
  • SPJ: [This is] clearly not a bug in GHC; but it would be more felicitous if it gave you a warning...
  • Gracenotes: > let o_o = 0.0 ;o' =(, ); ;o (*)=(*) ;( lol, xD :p )= o' o' $o.o$ (:[]) $o.o$ (:[]) o_o in (:[]) o_o :p
  • Cale: I plan on forming a symbiotic relationship with sandtrout, which, as they merge with my body, will sustain me as I slowly turn into a sandworm, and make use of my billions of other memories and prescience to rule over everyone and everything for millenia.
  • quicksilver: or in Java, we'd make it more generic by using a PolynomialDivisionOperatorFactory.
  • roconnor: I was going to read about laziness, but I decided to do it later, when I need to understand it.

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