Haskell Weekly News: August 14, 2006

Submitted by dons on Mon, 08/14/2006 - 1:10am.
Welcome to issue 40 of HWN, a weekly newsletter covering developments in the Haskell community. Each week, 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.

A mega super bumper issue, for the 1st birthday of the Haskell Weekly News


  • The Haskell Workshop . Andres Loeh announced the preliminary schedule of the Haskell Workshop 2006, part of the 2006 International Conference on Functional Programming (ICFP)

  • dbus haskell bindings . Evan Martin announced preliminary D-Bus Haskell bindings. D-Bus is a message bus system, a simple way for applications to talk to one another. More

  • The GHC typechecker is Turing-complete . Robert Dockins was able to show how that the GHC typechecker with multi-parameter typeclasses, functional dependencies, and undecidable instances is Turing-complete.

  • Haskell Program Coverage . Colin Runciman announced the first release of hpc, a new tool for Haskell developers. Hpc records and displays Haskell program coverage. It provides coverage information of two kinds: source coverage and boolean-control coverage. More here

  • Smash your boiler-plate without class and Typeable . Oleg Kiselyov described a new generic programming technique, expressive enough to traverse a term and return another term of a different type, determined by the original term's type/structure. More details

  • Paper: Software Extension and Integration with Type Classes . Ralf Laemmel and Klaus Ostermann invite comments towards the final version of their paper Software Extension and Integration with Type Classes

  • HSP.Clientside 0.01 . Joel Bj√∂rnson announced a release of his Summer of Code project HSP.Clientside 0.01. Present features include an embedding of (typed) JavaScript language in Haskell, a small combinator library for generating JavaScript code, and high-level interface to Ajax functionality.

  • Monadic probabilistic functional programing . Stefan Karrmann announced that he had extended Martin Erwig's PFP library to support abstract monads, cabal and darcs

  • hdbc-odbc . John Goerzen released DBC-odbc, the ODBC backend driver for HDBC, version

  • Few Digits 0.5.0 . Russell O'Connor This year, Few Digits competed in the More Digits contest. To celebrate, version 0.5.0 of Few Digits is available. Few Digits 0.5.0 is now ten times faster and three times more complicated. Few Digits has been Cabalized for your convenience. More info

  • System.FilePath 0.9 . Neil Mitchell announced System.FilePath 0.9

  • The History of Haskell . Phil Wadler, John Hughes, Paul Hudak and Simon Peyton Jones have been writing a paper, The History of Haskell, for the History Of Programming Languages conference (HOPL'07), and they invite feedback. Wiki page here.

  • AngloHaskell . Lemmih mentioned that AngloHaskell will be held at Cambridge in August. The agenda includes beer, unicycles, hacking and other fun. More info

  • Haskell XML Toolbox Version 6.0, 6.1 . Uwe Schmidt announced two new versions of the Haskell XML Toolbox. New features include ghc 6.4.2 support, better XPath integration, separate documentation for filter API and an arrow API

  • Down the rabbit hole . Bulat Ziganshin announced the availability of a new tutorial directed toward comprehensive explanation of the IO monad, and it's use in complex programs

  • ldap-haskell, arch2darcs and darcs-buildpackage . John Goerzen posted new versions of these packages

  • Internships on GHC and Haskell at MSR Cambridge . Simon Peyton-Jones announced that MSR Cambridge is taking interns year-round, not just in the summer months. GHC HQ are keen to attract motivated and well-qualified folk to work on improving or developing GHC. More details

  • FGL . Martin Erwig announced a new release of his well known Functional Graph Library (FGL).

  • Takusen . Alistair Bayley and Oleg Kiselyov released a new version of Takusen, a library for accessing DBMSs. The most significant code change is a new internal design, giving better separation of concerns like statement preparation, binding, and result-set processing. Takusen is now held in darcs, and hosted at haskell.org

  • Text.Regex.Lazy 0.44, 0.56, 0.66 and 0.70 . Chris Kuklewicz announced Text.Regex.Lazy 0.44-0.70, with many enhancements. Multiple backends are supported, in addition to the "full lazy" and the DFA backends. Text.Regex.Lazy is a replacement and enhancement for Text.Regex. More details here

  • Streams 0.2.1 beta . Bulat Ziganshin released Streams 0.2.1 beta, featuring various bug fixes and improvements to the streams library


This section covers the Haskell' standardisation process.


  • Package "mounting" . Sven Hallberg proposed drop the assumption that Haskell modules are closed entities, and rather always consider them to be seen in the context of a particular package.

  • Cabal and DLLs . Jason Dagit described how he was able to use Cabal with Visual Haskell to build Dlls in Windows.

  • Replacing GMP . Peter Tanski sparked a long discussion on the merits and difficulties of replacing the GMP numerical library used by GHC and nhc98 with a library using a less restrictive license. More here, here and here

  • The cost of Integer . Serge Mechveliani asked about the runtime cost of Integer, triggering an interesting discussion

  • Thread-local variables . Frederik Eaton started a large discussion on the merits or otherwise of thread-local variables.

  • Type level programming made simple . Oleg Kiselyov composed a useful comparison between Prolog and type level programming in Haskell

  • IRC channel statistics . Don Stewart created some graphs and analysis of activity and growth of the #haskell IRC channel

Quotes of the Week

  • Dan Piponi : "Writing introductions to monads seems to have developed into an industry"
  • John Meacham : "I liken learning Haskell to tipping over a vending machine. You can't just push it, you gotta rock it back and forth a few times building up momentum until bam! suddenly the flash of insight hits and it all makes sense."
  • Andrew Bromage : "What was considered 100 milli-Olegs of type hackery five years ago is standard operating procedure th ese days"
  • Tim Toady : "Learning Haskell itself is easy -- I've done it several times already"
  • Adam : "Lisp is like Ruby with an ugly syntax, impossible stdlib, and macros that don't compensate for above shortcomings"
  • Lennart A : "Hbc still has some unique features, like views. That I've never used.."
  • Edward K : "I've been playing with type level 2s complement arithmetic"
  • Edwin B : "I think I'd panic if I had to write something that wasn't a compiler"
  • Ozone : "Our C++ guru at work is getting a bit sick of me saying: Ah, so that's like in Haskell, but not quite as elegant..."
  • roconnor : "Life lesson from today: 1 closure is nice, 500 000 closures sucks"
  • scsibug : "I could have sworn it was incorrect until it type-checked"
  • stepcut : "I wrote 1 + 1 in php once, and got 11 -- wasn't quite what I was hoping for"

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