Welcome to issue 55 of HWN, a weekly newsletter covering developments in the Haskell community.

This week brings a new release of vty and HsColour, and some interesting discussion over the holiday break.

Announcements

hscolour-1.6. Malcolm Wallace announced HsColour, a popular syntax-highlighter for Haskell code. It can generate ANSI terminal colour codes, HTML, and CSS, and can insert hyperlink anchors for function definitions (useful in conjunction with Haddock). HsColour-1.6 is now available. The major addition is a new LaTeX output mode.

Dimensional: Statically checked physical dimensions. Björn Buckwalter announced version 0.1 of Dimensional, a module for statically checked physical dimensions. The module facilitates calculations with physical quantities while statically preventing e.g. addition of quantities with differing physical dimensions.

vty 2.0. Stefan O'Rear announced a new major version of vty. Differences from 1.0 include: vty now uses a record type for attributes, instead of bitfields in an Int; vty now supports setting background colors; you can now explicitly specify 'default' colors; vty now supports Unicode characters on output, automatically setting and resetting UTF-8 mode.

'Lambda Revolution' tshirts. Paul Johnson announced the creation of a new Haskell tshirt, on the theme of 'The Lambda Revolution'. Tshirts are available from CafePress, and the designs are freely available.

Discussion

Beautiful concurrency. Simon Peyton-Jones mentioned that he's been writing a chapter on concurrency and transactional memory for a new book, 'Beautiful code'. A first draft is available and Simon welcomes constructive suggestions for improvement. The book is aimed at a general audience of programmers, not Haskell geeks, so tries to explain everything necessary. If you are not a Haskell expert, your input would be particularly valuable.

Limits to implicit parallelism in functional applications. John DeTreville announced a short paper about how much implicit parallelism there might be in ordinary functional applications.

Inlining higher order functions. Norman Ramsey asked about fine grained control for inlining in higher order functions.

Red-black trees as a nested datatype. Jim Apple described how to implement red-black trees as a nested datatype.

SYB for XML: deserialization and collections. Alexander Jacobson asked about approaches to simplifying boilerplate in HAppS associated with XML serialization and state deserialization.

Flattening a lisp-style tree. pphetra asked about flattening heterogeneous lists (or trees) in Haskell.

Jobs

Functional programming at Jane Street Capital. Yaron Minsky announced that Jane Street Capital is again looking to hire some top-notch functional programmers. Of particular note is that Jane Street Europe Ltd. now has an office in London, and we are particularly interested in hiring someone for that office with strong systems administration skills in addition to experience with functional programming languages. The ideal candidate has: a commitment to the practical, experience with functional programming languages (such as Haskell). Applicants should also have experience with UNIX and a deep understanding of computers and technology and a strong mathematical background.

Blog noise

Haskell news from the blogosphere.

Quotes of the Week

Code Watch

Wed Dec 27 17:03:48 PST 2006. Manuel M T Chakravarty. Parse and desugar equational constraints. With -findexed-types, equational constraints can appear in contexts wherever class predicates are allowed. The two argument types need to be boxed and rank 0.

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