Welcome to issue 98 of HWN, a newsletter covering developments in the Haskell community.

Happy holidays! An exciting HWN for you this week, including a number of cool new libraries, the public release of Cryptol, a Haskell logo contest, and the second most awesome GHC bug ever (see augustss's quote at the end of the Quotes section for the most awesome GHC bug ever).

Announcements

Hieroglyph 0.85. Jeff Heard announced that the Thingie library has been renamed Hieroglyph, and now has support for displaying images on the Cairo canvas.

Cryptol now freely available. Don Stewart announced that Cryptol, the language of cryptography, is now available to the public! Cryptol is a domain specific language for the design, implementation and verification of cryptographic algorithms, developed over the past decade by Galois for the United States National Security Agency. It has been used successfully in a number of projects, and is also in use at Rockwell Collins, Inc. Cryptol is implemented in Haskell.

Control.Monad.IfElse. Jeff Heard announced the Control.Monad.IfElse module, which provides useful anaphoric and monadic versions of if-else and when.

llvm-0.4.0.1. Lennart Augustsson announced version 0.4.0.1 of the release that is quite incompatible with the old 0.0.2 release.) Haskell LLVM bindings. LLVM is a virtual machine and the bindings allow you to generate code for this virtual machine. This code can then be executed by a JIT or written to a file for further processing by the LLVM tools.

bytestring-trie 0.1.0. wren ng thornton announced the release of bytestring-trie 0.1.0, an efficient finite map from (byte)strings to values. The implementation is based on big-endian patricia trees, like Data.IntMap.

RWH book club. Don Stewart announced that Matt Podwysocki has set up a Real World Haskell book club, a mailing list on google groups with already some 200 members discussing typical new user Haskell questions. Feel free to join if you like talking about Haskell, or teaching new users.

Thingie-0.80. Jeff Heard announced the release of Thingie, a library for creating 2D visualizations in a purely functional manner. It supports static visualizations and animation, and like most vis libraries, can probably do games as well as simple viz graphics.

typehash version 1.3. Lennart Augustsson announced the release of the typehash library, which allows you to produce a unique identifier (a cryptographic hash) for a type. This is useful if you save values of some type to a file (text, binary, whatever format you wish) and then when you read it back in again you want to verify that the type you want to read is the one you actually wrote. The library also supports type codes, which encode the complete structure of a type and can be used for finer comparison than just equality.

uvector-algorithms 0.1. Dan Doel announced the release of uvector-algorithms, a library of algorithms (mostly sorting) for the mutable arrays defined in uvector. It has several varieties of sorting, including introsort (quicksort which falls back on heapsort in bad cases), heapsort, a simple top- down merge sort and a radix sort. Also exposed are the operations that allow you to use the arrays as heaps and a combinator for safely using these mutable array algorithms to sort immutable arrays. All algorithms have been painstakingly profiled and optimized.

Data.List.Split. Brent Yorgey announced the release of Data.List.Split, which provides a wide range of strategies and a unified combinator framework for splitting lists with respect to some sort of delimiter.

Hoogle with more libraries. Neil Mitchell announced that Hoogle will now search lots of the libraries present on hackage!

HLint 1.0. Neil Mitchell announced the re-release of HLint, a tool for making suggestions to improve your Haskell code. Previously this tool was called Dr Haskell and depended on a working installation of Yhc; now it depends on GHC 6.10.1.

rangemin-1.0. Louis Wasserman announced the release of rangemin, a library for efficiently preprocessing an array to find minimum elements of subranges of the array in constant time.

Discussion

length of module name affecting performance??. Daniel GorĂ­n reported a GHC bug where in certain cases, changing the name of a module to something longer results in a 2x-3x performance hit! Strange but true.

Time for a new logo?. Don Stewart proposed a competition to produce a new Haskell logo! Submissions should go on the wiki page; the deadline for logo submissions is December 31.

Pattern combinators. Andrew Wagner started a thread turning a paper on pattern-matching in Haskell into actual code for hackage.

Coroutines. Ryan Ingram posted some interesting code showing how to implement coroutines with session types.

Type wildcards. Eyal Lotem proposed a 'type wildcards' extension to the language.

Blog noise

Haskell news from the blogosphere.

Quotes of the Week

About the Haskell Weekly News

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