June 2009 - Haskell - Haskell.org

ANNOUNCE: numtype 1.0 -- Type-level (low cardinality) integers
by Bjorn Buckwalter 06 Jun '09

06 Jun '09

Dear all, Since its inception my dimensional library has been built around a unary type-level representation of integers (NumTypes) defined in the Numeric.NumType module. This module has proven itself useful outside the context of dimensional and after dragging my feet for a long time I've finally gotten around packaging it up in its own library: numtype[1]. The Numeric.NumType module is completely self-contained (only imports Prelude) and is heavily commented in a narrative manner inspired by Oleg Kiselyov's expositions. I believe it provides a good case study for type-level programming with multi-parameter type classes and functional dependencies. Addition, subtraction, division, and multiplication of NumTypes is supported. NumTypes have no value-level representation but can be converted to any Num instance with the 'toNum' function. The numtype library has two significant short-comings: * Minimal haddocks -- as with my dimensional library the literate Haskell source code is the documentation. The flip-side is that the code is very well-commented. * Due to the unary implementation the practical size of the NumTypes is severely limited, making them unsuitable for large-cardinality applications. If you will be working with integers beyond (-20, 20) this package probably isn't for you. (If the second bullet is a show-stopper Edward Kmett's type-int[2] library may be a better choice. Peter Gavin's tfp[3] library also provides type-level integers but uses type families instead of MPTCs and fundeps. I cannot vouch for either of these libraries as I haven't used them.) Numtype version 1.0 can be downloaded from Hackage or the dimensional project page[4]. I've also updated dimensional to version 0.8 with the Numeric.NumType module removed and Julian 'year' and 'century' units added. Enjoy! Thanks, Bjorn Buckwalter [1]: http://code.google.com/p/dimensional/wiki/numtype [2]: http://hackage.haskell.org/cgi-bin/hackage-scripts/package/type-int [3]: http://hackage.haskell.org/cgi-bin/hackage-scripts/package/tfp [4]: http://dimensional.googlecode.com

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Haskell Weekly News: Issue 120 - June 6, 2009
by Brent Yorgey 06 Jun '09

06 Jun '09

--------------------------------------------------------------------------- Haskell Weekly News http://sequence.complete.org/hwn/20090606 Issue 120 - June 06, 2009 --------------------------------------------------------------------------- Welcome to issue 120 of HWN, a newsletter covering developments in the [1]Haskell community. Sorry for the massive HWN, I missed last week so you're getting two for the price of one! Registration for [2]Hac phi is now open, be sure to register soon (register by June 15 to get a special hotel rate). Announcements Reminder: Haskell Implementers' Workshop CFT deadline in 2 weeks. Simon Marlow [3]reminded everyone to consider submitting a talk proposal for the Haskell Implementers' Workshop, to be held in conjunction with ICFP in Edinburgh, Scotland on 5 September. The deadline for submissions is a couple of weeks away (15 June); all that is needed is an abstract. storable-record. Henning Thielemann [4]announced [5]storable-record, a small package for simplified declaration of Storable instances for records. It may be used as an alternative to the [6]c2hs preprocessor. It was made possible by advanced applicative technology, a cutting edge LCM monoid and an incredible constructor power tower. Haskell Communities and Activities Report (16th ed., May 2009). Janis Voigtlaender [7]announced the availability of the [8]16th Haskell Communities and Activities Report. hledger 0.5 released. Simon Michael [9]announced the release of version 0.5 of [10]hledger, a (mostly) text-mode double-entry accounting tool that generates precise activity and balance reports from a plain text journal file. New repository and trac for haskell-src-exts. Niklas Broberg [11]announced some new infrastructure for the haskell-src-exts package, set up in preparation for his GSoC project. with the HSP packages, it's now old enough to be allowed to [12]live on its own. There is also a [13]bug tracker. Please help by reporting any bugs you come across, or by requesting new and cool features. bsd-sysctl 1.0.3. Maxime Henrion [14]announced the release of [15]bsd-sysctl 1.0.3, a package that provides a System.BSD.Sysctl module allowing access to the C sysctl(3) API. It should fully work on FreeBSD, NetBSD and Mac OS X platforms. multirec-binary. Sebastiaan Visser [16]announced the release of [17]multirec-binary, which allows generic derivation of Data.Binary instances using the [18]MultiRec library. notice for package authors. Duncan Coutts [19]announced that Hackage uploads will soon require an upper bound on the version of the base package and reject packages that omit it. This will hopefully result in less breakage the next time a new version of the base package is released. (Pre-) Announce: Data.GDS 0.1.0. Uwe Hollerbach [20](pre-) announced Data.GDS, a small module to write and (eventually) read GDS files, a classic format of the semiconductor industry. The module can currently generate GDS files with a fairly low-level interface; planned future versions (which will be uploaded to Hackage) will have a higher-level interface and be able to parse GDS files as well. new version of uu-parsinglib. S. Doaitse Swierstra [21]announced that a new version of the [22]uu-parsinglib library has been uploaded to hackage. It is now based on Control.Applicative where possible. Be warned that functions like some and many will be redefined in the future. Hac phi: Haskell hackathon in Philadelphia, July 24-26. Brent Yorgey [23]announced Hac phi, a Haskell hackathon/get-together to be held July 24-26 at the University of Pennsylvania in Philadelphia. The hackathon will officially kick off at 2:30 Friday afternoon, and go until 5pm on Sunday (with breaks for sleep, of course). Everyone is welcome---you do not have to be a Haskell guru to attend! Helping hack on someone else's project could be a great way to increase your Haskell-fu. If you plan on coming, please [24]register. There is a block of hotel rooms available at a special rate only until June 15, so register early! More details can be found on the [25]Hac phi wiki. Job for someone: make a VM image for GHC development. Simon Marlow [26]suggested a useful project for someone looking for something to do: create a VM image of a Linux system with a complete GHC development environment set up and ready to go. My attempt at Haskell USB. Mauricio [27]announced some [28]Haskell bindings to libusb, and gave another plug for his [29]bindings-common package, which makes it easier to generate Haskell bindings to low-level libraries. second alpha release of OSX haskell platform installer. Gregory Collins [30]announced a [31]second candidate release for the OSX Haskell Platform installer. Please try it out! Release Schedule for 2009.2.0.2. Don Stewart [32]announced the [33]release schedule for the next minor release of the 2009.2.0 branch of the Haskell Platform. The freeze for package changes will be Wednesday 1 July, and the release is scheduled for Monday 13th July. hscamwire, for IIDC1394 cameras. Frederick Ross [34]announced the release of [35]hscamwire 0.1, which provides a nice Haskellized layer over Camwire, a library to connect to IIDC1394 cameras (most scientific and industrial Firewire cameras) on Linux. Safe and generic printf with C-like format string. oleg [36]announced some code to implement a type-safe polyvariadic version of printf, which is also integrated with Show so that any showable type can be printed. A library for serial ports. Frederick Ross [37]announced the release of [38]serial-0.1, a library for line-oriented interaction with serial ports on POSIX compatible systems. HaL4: Haskell-Meeting in Germany, 12th June 2009. Janis Voigtlaender [39]reminded everyone of [40]Hal4, a German-language Haskell gathering to be held in Halle/Saale on June 12. There are already close to 50 registered participants, so expect a very lively meeting! Late registration still possible. wp-archivebot 0.1 - archive Wikipedia's external links in WebCite. Gwern Branwen [41]announced [42]wp-archivebot, a relatively simple little script which follows all the links in a RSS feed, combs the destination for http:// links, and submits them to [43]WebCite. memscript-0.0.0.2. Ki Yung Ahn [44]announced [45]memscript, a command line utility for memorizing scriptures or any other text. HSH 2.0.0. John Goerzen [46]announced the release of [47]version 2.0.0 of HSH, the Haskell shell scripting library. This version features a complete rewrite of the core using System.Process, a drastic reduction in code size and complexity, cross-platform support, and a simpler and more flexible API. atom-0.0.5. Tom Hawkins [48]announced version 0.5 of the [49]atom library, a DSL for embedded hard realtime applications. This version includes a few bug fixes and doc improvements. heap-1.0.0. Stephan Friedrichs [50]announced a rewrite of the heap package, [51]heap-1.0.0. It is not 100% compatible with version 0.6.0, but provides major improvements, including a better mechanism for instantiating min-, max-, min-prio- and max-prio-heaps, and faster {from,to}{Asc,Desc}List conversions. The Haskell Platform 2009.2.0.1. Don Stewart [52]announced the second release (2009.2.0.1) of the [53]Haskell Platform, a single, standard Haskell distribution for everyone. The specification, along with installers (including Windows and Unix installers for a full Haskell environment) are available. Anglohaskell 2009. Philippa Cowderoy [54]announced [55]Anglohaskell 2009, to be held at MSR Cambridge on the 7th and 8th of August. code reviewers wanted for hashed-storage (darcs). Eric Kow [56]solicited anyone with a few spare hours this summer willing to help the Darcs project as a code reviewer for the standalone hashed-storage module, which will be used by Darcs in the future. No Darcs experience is needed! Google Summer of Code Progress updates from participants in the 2008 [57]Google Summer of Code. Haddock improvements. Isaac Dupree has begun looking at the Haddock code, and has a [58]question about which of two options he should pursue. EclipseFP. Thomas Ten Cate has posted an [59]explanation of how the Scion client/server model works. Space profiling. Gergely Patai has [60]uploaded a preliminary version of the [61]hp2any core library which handles heap profiles both during and after execution. He has also [62]posted some pretty graphs generated by a simple utility built on top of the core library. haskell-src-exts. Niklas Broberg has begun work by making a [63]list of all language extensions and the ways in which they affect lexing and parsing, since haskell-src-exts will need to be parameterized over these extensions. Fast Darcs. Petr Rockai has posted two detailed [64]progress [65]reports already, with many changes to both the standalone [66]hashed-storage library and a [67]fork of darcs which uses it. Discussion Error message reform (was: Strange type error with associated type synonyms). Max Rabkin began an interesting [68]discussion about error messages. Do you have an intuitive sense of which is the 'expected' and which the 'inferred' type? time library dependencies. Ashley Yakeley [69]asked what dependencies are acceptable for the time library, leading to a discussion of what dependencies are acceptable for base packages. Bool as type class to serve EDSLs. Sebastiaan Visser started a [70]discussion on the possibility of a type class for representing Boolean values, much like the current Num class for numeric values. Jobs 10 jobs in declarative programming. Oege de Moor [71]announced the availability of positions with Semmle and LogicBlox for ten declarative programming consultants, who will work with clients to write custom queries in Datalog, and to create user interfaces in a declarative framework. Semmle and LogicBlox are creating a platform for declarative programming in Datalog, a pure logic programming language. Semmle is based in Oxford, headed by Oege de Moor; LogicBlox is based in Atlanta, headed by Molham Aref. See the announcement for more information and how to apply. Blog noise [72]Haskell news from the [73]blogosphere. Blog posts from people new to the Haskell community are marked with >>>, be sure to welcome them! * David Amos: [74]Welcome to Haskell for Maths. David's Haskell library for mathematics exploration is under development again! * Joachim Breitner: [75]Third place in AI programming contest. * Bryan O'Sullivan: [76]Dealing with encoding errors in Data.Text. * Remco Niemeijer: [77]Programming Praxis - Ternary Search Tries. * beelsebob: [78]Collecting Non-Memory Resources. * Luke Palmer: [79]It is never safe to cheat. Ceiling cat is watching you. * Alex McLean: [80]More hackery. More cool livecoding with Haskell. * Thomas ten Cate: [81]Client/server communication. * Gergely Patai: [82]The first graphs. * Alson Kemp: [83]Turbinado V0.6.5. * Don Stewart (dons): [84]The Haskell Platform 2009.2.0.1. The first minor update release of the Haskell Platform is here. * Alson Kemp: [85]Turbinado V0.6.5. * Michael Snoyman: [86]Functors and Monads (containers). * Well-Typed.Com: [87]Come talk at the Haskell Implementers' Workshop!. * GSoC Fast Darcs: [88]soc progress 2. * Shin-Cheng Mu: [89]On a Basic Property for the Longest Prefix Problem. * >>> Ben Hutchison: [90]OO/Imperative programmers: 'Study Functional Programming or Be Ignorant'. * Michael Snoyman: [91]Run a MonadCGI as a CGI application!. * Michael Snoyman: [92]Wordify: RESTful Haskell web apps. * Marco Tulio Gontijo e Silva: [93]xmlGetWidget without castTo*. * >>> slawekk: [94]Probability monad. * Brandon Simmons: [95]Huffman Coding. * Niklas Broberg: [96]Parametrising haskell-src-exts on extensions. A list of language extensions and how they affect parsing. * Manuel M T Chakravarty: [97]Instant Generics now has a website!. * GHC / OpenSPARC Project: [98]The CAS experiment. * Brent Yorgey: [99]Hac phi!. Registration is now open. * Jeff Heard: [100]Buster 2.2 - Application Orchestration redux. Example code showing off Buster. * Bryan O'Sullivan: [101]I put a pidgit in your widget so you can fidget while you calculate pi. GHC and the language shootout. * Niklas Broberg: [102]Haskell Platform, I'm in love. * Bjorn Buckwalter: [103]Benchmarking Amazon EC2 with GHC. * Bjorn Buckwalter: [104]Blogging with Pandoc, literate Haskell, and a bug. * >>> Chris Moos: [105]Haskell AIM Client - a cool proof of concept. * Marco Tulio Gontijo e Silva: [106]Generating code with Haskell-src and TH. Quotes of the Week * pumpkin: we should throw it [CReal] in with Foreign.C.Types to confuse people * MyCatVerbs: The *real* best way to optimize a program is to tell dons that it's been added to the Shootout. * SimonFrankau: The points-free approach, while elegant, can make code unreadable, especially if it is written by quantitative analysts moonlighting as functional programmers. * ValarQ: l33t_h4x0r: could you help me port GHC to the AVR architecture? <-- l33t_h4x0r has left #haskell * gwern: drat. what *do* all you people talk about? only one bacon and one zombie quote * quicksilver: well if you can get proggit to help with your interview, then perhaps you can get proggit to help with the job when you get it. So it's not cheating, it's just an indication of one of your skill sets. * shapr: I haven't tried F#, everytime I get the urge to do something fun with .NET I have SharePoint flashbacks and buy more hardware instead. * gwern: bleh. haskell is messing me up. I wondered what operator =) is, before I realized it was a syntax error, before I realized it was an emoticon About the Haskell Weekly News New editions are posted to [107]the Haskell mailing list as well as to [108]the Haskell Sequence and [109]Planet Haskell. [110]RSS is also available, and headlines appear on [111]haskell.org. To help create new editions of this newsletter, please see the information on [112]how to contribute. Send stories to byorgey at cis dot upenn dot edu. The darcs repository is available at darcs get [113]http://code.haskell.org/~byorgey/code/hwn/ . 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hscamwire, for IIDC1394 cameras
by Frederick Ross 05 Jun '09

05 Jun '09

hscamwire 0.1 is now on Hackage. It provides a nice Haskellized layer over Camwire, a library to connect to IIDC1394 cameras (most scientific and industrial Firewire cameras) on Linux. The binding exposes all of Camwire's functionality, except that the only mode for fetching frames is 16-bit monochrome. Adding more modes is quite easy, but this is all I use. If you have a need for another mode, email me and I'll add it. There is no documentation in the package at the moment. I will release a new version fairly soon once I have Haddock'd it, but there is a lot of detail in clib/camwire/camwire.h on the C side, and it translates nearly directly to the Haskell side. Camwire itself is kind of in flux right now as its author upgrades to a new underlying subsystem. As a result, I provide camwire 0.8.1 in a subdirectory (clib/) along with a Makefile to build and install it. When you compile code linking to hscamwire, you'll have to also link against camwire_1394. -- Frederick Ross Doctorant, SV/GHI/UPKIN, EPFL Graduate Fellow, The Rockefeller University

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Safe and generic printf with C-like format string
by oleg＠okmij.org 05 Jun '09

05 Jun '09

The familiar printf is unsafe: nothing prevents us from passing to printf more or fewer arguments than required by the format specification, or passing the arguments of wrong types. The error is discovered only at run-time. The implementation of printf in Haskell, alas, retains this problem. There is also a desire to better integrate printf with Show, so we can format the value of any showable type: we'd like to have something like the ~a specification of Common Lisp. Integrating printf with show, thus making it generic, is quite easy. The implementation is still Haskell98. It has just been posted: http://www.haskell.org/pipermail/haskell-cafe/2009-June/062410.html Given its simplicity, one may wonder why it was not mentioned in the Haskell98 report or included in standard libraries. The safety problem still remains: we'd like to prevent the mismatch between the arguments of printf and the format specification statically. That too is easy to accomplish. Type-safe printf has been described by Olivier Danvy back in 1998. It is part of SML/NJ. The only remaining bit is to convert the formatting _string_ to the more representative and more useful to the type-checker form. That too is easy, with Template Haskell (as Ryan Ingram remarked). The following code implements that suggestion. Aside from the use of template Haskell, it is Haskell98. Beside the familiar format specifications %s and %d, in implements the specification %a to format any showable value. The code is available at http://okmij.org/ftp/typed-formatting/TotalPrintF.hs http://okmij.org/ftp/typed-formatting/TFTest.hs The second file contains these examples: module TFTest where import TotalPrintF t1 = printf $(spec "Hello, there!") -- "Hello, there!" t2 = printf $(spec "Hello, %s!") "there" -- "Hello, there!" t3 = printf $(spec "The value of %s is %d") "x" 3 -- "The value of x is 3" -- Mismatch between the formatting string and the printf arguments -- is a type error. -- t31 = printf $(spec "The value of %s is %d") "x" True -- Couldn't match expected type `Bool' against inferred type `Int' {- t32 = printf $(spec "The value of %s is %d") "x" 3 10 Couldn't match expected type `t1 -> t' against inferred type `String' Probable cause: `printf' is applied to too many arguments -} t4 = let x = [9,16,25] i = 2 in printf $(spec "The element number %d of %a is %a") i x (x !! i) -- "The element number 2 of [9,16,25] is 25"

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ANN: wp-archivebot 0.1 - archive Wikipedia's external links in WebCite
by Gwern Branwen 04 Jun '09

04 Jun '09

I'd like to announce wp-archivebot. # What wp-archivebot is a relatively simple little script which follows all the links in a RSS feed, combs the destination for http:// links, and submits them to WebCite. WebCite https://secure.wikimedia.org/wikipedia/en/wiki/WebCite is an organization much like the more famous Internet Archive. Unlike the Wayback Machine, however, WebCite will archive pages on-demand.* # Why This is good, since link-rot and 404 errors are a fact of life on Wikipedia. Links go stale, fall dead, get banned, edited, censored, etc. If those links are being used as a reference for some important fact or detail, then there is a very big problem. Even the hit-or-miss Internet Archive has proven to be very useful for editors**, so a more reliable way of archiving links would be even better. # Limitations The WebCite FAQhttp://webcitation.org/faq mentions that a good project would be to > develop a wikipedia bot which scans new wikipedia articles for cited URLs, submits an archiving request to WebCite®, and then adds a link to the archived URL behind the cited URL Adding a link would be both quite difficult and require community approval; further, although I have thought about this for years, there's no obvious good way to add a link. Any method is either visually awkward, possibly otiose (if [[Google]] links to google.com as the homepage in its infobox, there's no purpose to have an archived version of google.com!) and certainly will bloat up the markup - even if there's any way to insert links without bolloxing templates and other such constructs. So I'm satisfied to just archive the link. WebCite is searchable, after all. If enough people run bots like this and achieve enough coverage, then perhaps editors can be educated to always check in WebCite as well. # Download & Install As ever, wp-archivebot is Free and is available from Hackage at: http://hackage.haskell.org/cgi-bin/hackage-scripts/package/wp-archivebot You can install with ease by a simple 'cabal install wp-archivebot', or download the tarball and compile it yourself with the usual 'runhaskell Setup configure && runhaskell Setup build && runhaskell Setup install' dance. # Usage wp-archivebot takes one mandatory argument, an email address; WebCite needs to have somewhere to send notices of archival success/failure. wp-archivebot takes a second, optional, argument. This is a RSS feed to use. It defaults to Special:NewPages on the English Wikipedia, but one could just as well follow, say, RecentChanges. Here's an example: > wp-archivebot gwern0(a)gmail.com 'http://en.wikipedia.org/w/index.php?title=Special:RecentChanges&feed=rss' (This sets my email address as the recipient, and follows RecentChanges. This may not be a good idea as RecentChanges is *much* busier than NewPages.) ## Example Here's an example session's output: [12:35 PM] 829Mb$ wp-archivebot gwern0(a)gmail.com "http://www.webcitation.org/archive?url=http://en.wikisource.org/wiki/Berkel…" "http://www.webcitation.org/archive?url=http://www.baseball-reference.com/pl…" "http://www.webcitation.org/archive?url=http://www.baseball-reference.com/pl…" "http://www.webcitation.org/archive?url=http://www.baseball-reference.com/mi…" "http://www.webcitation.org/archive?url=http://www.baseball-reference.com/mi…" "http://www.webcitation.org/archive?url=http://www.timesargus.com/apps/pbcs.…" "http://www.webcitation.org/archive?url=http://www.timesargus.com/apps/pbcs.…" "http://www.webcitation.org/archive?url=http://www.timesargus.com/apps/pbcs.…" "http://www.webcitation.org/archive?url=http://www.timesargus.com/apps/pbcs.…" "http://www.webcitation.org/archive?url=http://www.erniestires.net/&email=gw…" "http://www.webcitation.org/archive?url=http://www.erniestires.net/&email=gw…" "http://www.webcitation.org/archive?url=http://thepeerage.com/p4893.htm#i489…" "http://www.webcitation.org/archive?url=http://thepeerage.com/p4893.htm#i489…" "http://www.webcitation.org/archive?url=http://www.leighrayment.com/commons/…" "http://www.webcitation.org/archive?url=http://www.leighrayment.com/commons/…" "http://www.webcitation.org/archive?url=http://thepeerage.com/p4893.htm#i489…" "http://www.webcitation.org/archive?url=http://thepeerage.com/p4893.htm#i489…" "http://www.webcitation.org/archive?url=http://www.esec.edu&email=gwern0@gma…" "http://www.webcitation.org/archive?url=http://www.esec.edu&email=gwern0@gma…" ... # Related The development version (HEAD) of the Gitit wiki has plugin support; one of those plugins, WebArchiver.hs, will on every page-save comb through for off-wiki links and submit them to WebCite in the same way as this bot. It's nice to know that if those links ever disapear, you can retrieve them from WebCite and 'see' the revision with the same set of external links as when the revision was created. * Technically, the Internet Archive will archive on demand as well - but you need to pay them. ** In many more ways than one might expect. For example, not infrequently someone will visit an article and claim it is plagiarizing some other webpage. With the IA, it's easy to go back to the first version of that webpage and crosscheck against the article's history - quite often it is the other website that plagiarized us! -- gwern

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A library for serial ports
by Frederick Ross 03 Jun '09

03 Jun '09

I've just uploaded serial-0.1, a library for line-oriented interaction with serial ports on POSIX compatible systems, to Hackage: http://hackage.haskell.org/cgi-bin/hackage-scripts/package/serial At the moment it's just two modules, one of which wraps up the serial connection in a convenience function (System.Serial), and the other (System.Serial.Manager) which further wraps a serial connection in a set of functions to let multiple commands go to a non-blocking device on the far end of the port and, with the proper parsers and a little luck, get the responses sent back to all the right calling functions. The interface is not final yet. I'm using Parsec parsers passed with the command to sort out where return values should go, and that may just become predicates later. Also, if someone who actually knows anything about programming on Windows wants to add that capability, I'd be thrilled. -- Frederick Ross Doctorant, SV/GHI/UPKIN, EPFL Graduate Fellow, The Rockefeller University

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[Haskell] The speed, size and dependability of programming languages
by Bulat Ziganshin 02 Jun '09

02 Jun '09

Hello haskell, Interesting blog post comparing speed and expressiveness of many languages: http://gmarceau.qc.ca/blog/2009/05/speed-size-and-dependability-of.html -- Best regards, Bulat mailto:Bulat.Ziganshin@gmail.com

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ANN: Anglohaskell 2009
by Philippa Cowderoy 02 Jun '09

02 Jun '09

Anglohaskell 2009 is go! I'm taking on the mantle of organiser, and Microsoft Research have offered us space for talks in Cambridge again. The event will be held on the 7th and 8th of August. More info at http://www.haskell.org/haskellwiki/AngloHaskell/2009 , planning and discussion in #anglohaskell on freenode. For those not familiar with Anglohaskell, it's a somewhat-informal get-together featuring a mixture of talks, discussion and socialising with topics from the hobbyist to the pragmatic to the theoretical. All are welcome, regardless of experience, and best of all - it's free! If anyone wants to offer a talk, help with running the event, accomodation for haskellers from out of town or some ideas, please feel free to edit the wiki page appropriately and/or give us a yell in #anglohaskell. -- Philippa Cowderoy <flippa(a)flippac.org>

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ANNOUNCE: The Haskell Platform 2009.2.0.1
by Don Stewart 02 Jun '09

02 Jun '09

We're pleased to announce the second release of the Haskell Platform: a single, standard Haskell distribution for everyone. The specification, along with installers (including Windows and Unix installers for a full Haskell environment) are available. Download the Haskell Platform 2009.2.0.1: http://hackage.haskell.org/platform/ The Haskell Platform is a blessed library and tool suite for Haskell distilled from Hackage, along with installers for a wide variety of systems. It saves developers work picking and choosing the best Haskell libraries and tools to use for a task. Distro maintainers that support the Haskell Platform can be confident they're fully supporting Haskell as the developers intend it. Developers targetting the platform can be confident they have a trusted base of code to work with. What you get: http://hackage.haskell.org/platform/contents.html With regular time-based releases, we expect the platform will grow into a rich, indispensable development environment for all Haskell projects. Please note that this is a beta release. We do not expect all the installers to work perfectly, nor every developer need met, and we would appreciate feedback. You can help out by packaging the platform for your distro, or reporting bugs and feature requests, or installing Haskell onto your friends' machines. The process for adding new tools and libraries will be outlined in coming weeks. The Haskell Platform would not have been possible without the hard work of the Cabal development team, the Hackage developers and maintainers, the individual compiler, tool and library authors who contributed to the suite, and the distro maintainers who build and distribute the Haskell Platform. Thanks! -- The Platform Infrastructure Team

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HaL4: Haskell-Meeting in Germany, 12th June 2009
by Janis Voigtlaender 02 Jun '09

02 Jun '09

Hi all, If you are anyway near Halle/Saale in June, be sure not to miss out on: http://iba-cg.de/hal4.html We have already close to 50 registered participants, so expect a very lively meeting. See you there? (Late registration still possible.) Ciao, Janis. -- Dr. Janis Voigtlaender http://wwwtcs.inf.tu-dresden.de/~voigt/ mailto:voigt@tcs.inf.tu-dresden.de

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