Haskell Weekly News: November 14, 2006
Welcome to issue 49 of HWN, a weekly newsletter covering developments in the Haskell community.
Major typeclass overhaul. Simon Peyton-Jones mentioned that for some time he has been promising an overhaul of GHC's type inference machinery to fix the interactions between type classes and GADTs. This overhaul has now been completed, and user-visible changes are summarised, including: GHC's type inference becomes complete, the restriction that every constraint in a type signature must mention at least one of the quantified type variables is lifted, dictionaries are packaged in data constructors and the proper interaction between GADTs and type classes is now respected.
Great language shootout: reloaded. Don Stewart mentioned that now GHC 6.6 is available on the shootout machines, the time has come to improve the existing language shootout entries. Improvements can be posted to the wiki for review.
Haskell'This section covers the Haskell' standardisation process.
LibrariesThis week's proposals and extensions to the standard libraries.
Choosing a Haskell GUI library. Bulat Ziganshin asked for advice on which Haskell gui library to use. Several suggestions were made.
Conference roundupAsian Symposium on Programming Languages and Systems (APLAS 2006)
Type Processing by Constraint Reasoning. Peter Stuckey. Paper.
Principal Type Inference for GHC-Style Multi-Parameter Type Classes. Martin Sulzmann, Tom Schrijvers and Peter J Stuckey. Paper.
Automatic Testing of Higher Order Functions. Pieter Koopman and Rinus Plasmeijer. Paper.
Research position in spatial cognition (Haskell-related). Till Mossakowski announced the availability of a Doctoral Research Assistant / Postdoctoral Researcher position at the Universität Bremen, concerned with classification and formalization of qualitative spatial calculi, relations among these calculi, spatial ontologies, and route graphs. More information.
Blog noiseHaskell news from the blogosphere.
- Getting real with Haskell
- A Simple RPN Calculator in Haskell
- One more grunt trying to learn Haskell
- Testing Telecoms Software with Quviq QuickCheck
- Quviq QuickCheck: A new automated testing tool
- My first Haskell adventure game!
Quotes of the Week
- dylan: I remember being introduced to lambdas (in perl) from the programming perl, 2nd edition book. I used them heavily ever since... like some kind of cocaine addiction.
- jdunck: What's your safeword?
- sketerpot: With very strict typing, you need an *unsafe*word.
- Binkley: Can you represent 'more moronic than Slashdot' with a 32-bit integer?
- Robert Dockins: A Turing-complete type-checker isn't enough! Our work is not complete until the parser is a universal machine as well!
- dons: Disable the type checker in GHC for 6 months and we'd have 5 Haskell debuggers by the end of it.
- lennart: System Verilog is one of the worst 'designs' I've ever seen. So I bet it will be popular
- lispy: The biggest reason most developers I know don't fix a bug is because they don't know it exists yet
- monochrom: Time flies like an arrow. Fruit flies like a banana. Syntax rules like a macro
- robreim: [on the new #haskell lojban channel] Great, now we've got to start an IRC channel for lojban-speaking, Haskell-coding anarchists
- syntaxfree: Yes, Wadlerman: Prince of Funktions
2006-11-09 17:01:33 GMT. Claus Reinke. Syntax patch for lambda-match.
2006-11-06 21:27:30 GMT. Lennart Kolmodin. New ghc-pkg option 'check'. A patch for ghc-pkg show broken packages (due to missing dependencies) with a new command 'check', and also indicate broken packages when using the command 'list'.
2006-11-10 13:43:26 GMT. Simon Peyton Jones. Use implication constraints to improve type inference.
2006-11-13 09:36:19 GMT. Simon Peyton Jones. Add literal-shift rewrite rules.
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