Haskell Weekly News: February 20, 2006

Greetings, and thanks for reading issue 25 of HWN, a weekly newsletter covering developments in the Haskell community. Each Monday, new editions are posted to the Haskell mailing list and to The Haskell Sequence. RSS is also available.

Announcements

• The Haskell Workshop. Andres Loeh released the initial call for papers for the ACM SIGPLAN 2006 Haskell Workshop, to be held at Portland, Oregon on the 17 September, 2006.

  The purpose of the Haskell Workshop is to discuss experience with Haskell, and possible future developments for the language. The scope of the workshop includes all aspects of the design, semantics, theory, application, implementation, and teaching of Haskell.

• Probability Distributions. Matthias Fischmann released a module for sampling arbitrary probability distribution, so far including normal (gaussian) and uniform distributions.
• Constructor Classes. Sean Seefried announced an implementation of a tool to help explore constructor classes (type classes which can take constructors as arguments) described in Mark Jones' paper, A system of constructor classes: overloading and implicit higher-order polymorphism. The implementation not only infers the type but also prints out a trace of the derivation tree for the syntax directed rules.

Haskell'

• Status Report. Isaac Jones released a Haskell' status report. There is a list of proposals and a "strawman" categorization of them on the wiki. The timeline is also on the wiki. You'll notice that it's very aggressive; we plan to announce something at the next Haskell Workshop in September. So, check out the wiki and get on the haskell-prime mailing list!

• More on strictness
• FFI Pragmas
• Pattern synonyms
• The MPTC Dilemma
• Labels and the MPTC Dilemma
• The way forward
• Export lists
• First class labels
• Standardising the compiler interface
• An existential quantifier

Discussion

• Commerical Use of Haskell. Seth Kurtzberg mentioned on the #haskell irc channel that he was in the process of deploying a commercial application written in Haskell onto a production line in Taiwan. The particular application stress tests hardware performance and stability.

  Seth writes:

  Once the compiler finally does what I think I'm telling it, the programs almost always work the first time, which is really amazing. With any substantial effort in C or C++, you are going to have hidden problems traceable to type errors.

  Recently, the thing that I was most pleased with was how quickly I was able to refactor the hardware stress testing code into network performance testing code.

• RFC: Class-based collections. Jean-Philippe Bernardy released an rfc for his initial work on a class-based collections framework. The main goal is to have something usable right now, making use of generally available haskell extensions for maximum usability/portability ratio (or rather product).

Darcs Corner

• darcs 1.0.6. Tommy Pettersson announced that the initial release candidate for Darcs 1.0.6 is available. It contains important bug fixes, some noticeable changes, and, of course, new features.

Contributing to HWN

You can help us create new editions of this newsletter. Please see the contributing information, send stories to dons -at- cse.unsw.edu.au. The darcs repository is available at darcs get http://www.cse.unsw.edu.au/~dons/code/hwn