September 2007 - Haskell

Haskell Weekly News: September 23, 2007
by Don Stewart 24 Sep '07

24 Sep '07

--------------------------------------------------------------------------- Haskell Weekly News http://sequence.complete.org/hwn/20070923 Issue 65 - September 23, 2007 --------------------------------------------------------------------------- Welcome to issue 65 of HWN, a newsletter covering developments in the [1]Haskell community. This episode comes to you live from Portland, Oregon, where the HWN automaton now lives, running on a virtual host at Galois, Inc. 1. http://haskell.org/ Announcements Cabal 1.2.0 released. Thomas Schilling [2]announced that [3]Cabal version 1.2.0 is available. The major new feature in this release is support for Cabal configurations. This allows package authors to more easily adopt their package descriptions to different system parameters such as operating system, architecture, or compiler. In addition, some optional features may be enabled or disabled explicitly by the package user. 2. http://article.gmane.org/gmane.comp.lang.haskell.libraries/7491 3. http://www.haskell.org/cabal SparseCheck. Matthew Naylor [4]announced SparseCheck, a library for typed, depth-bounded logic programming in Haskell allowing convenient expression of test-data generators for properties with sparse domains. More information on the [5]home page. 4. http://article.gmane.org/gmane.comp.lang.haskell.general/15593 5. http://www.cs.york.ac.uk/~mfn/sparsecheck/ monadLib 3.3.0. Iavor Diatchki [6]announced a new version of monadLib, adding the identiy transformer, and a family of deriving functions. 6. http://article.gmane.org/gmane.comp.lang.haskell.general/15586 ListLlke. John Goerzen [7]announced ListLike, a generic interface to the various list-like structures in Haskell. 7. http://article.gmane.org/gmane.comp.lang.haskell.general/15582 HaL2: Meeting Haskell in Leipzig 2: videos. Klaus Meier [8]announced that the videos and presentations of the talks given at HaL2 are [9]now online. 8. http://article.gmane.org/gmane.comp.lang.haskell.general/15565 9. http://iba-cg.de/haskell.html The Monad.Reader: Issue 8. Wouter Swierstra [10]announced that the latest issue of The Monad.Reader is [11]now available. Issue 8 consists of the following two articles: Brent Yorgey on 'Generating Multiset Partitions' and Conrad Parker's 'Type-Level Instant Insanity' 10. http://article.gmane.org/gmane.comp.lang.haskell.general/15554 11. http://www.haskell.org/haskellwiki/The_Monad.Reader Haskell mode plugins for Vim. Claus Reinke [12]announced improved [13]haskell mode plugins for vim. 12. http://article.gmane.org/gmane.comp.lang.haskell.general/15553 13. http://article.gmane.org/gmane.comp.lang.haskell.general/15553 hstats-0.1. Marshall Beddoe [14]announced a statistical computing module for Haskell. 14. http://article.gmane.org/gmane.comp.lang.haskell.cafe/28973 HIntegerByInt. Isaac Dupree [15]announced a [16]reimplementation, in Haskell, of the Integer type that Haskell provides in its Prelude. It is designed in mind of being actually usable as the implementation of that type, for compilers. It is also a module that exports a working Integer type. It is in terms of only basic Prelude functions, lists, and Int. It is NOT a purely inductive definition, because Int is much faster than a purely inductive definition would allow, and nevertheless often easier to come by (more portable, license-wise, size-wise, nuisance-wise...) than GMP or other C bignum libraries. 15. http://thread.gmane.org/gmane.comp.lang.haskell.libraries/7285 16. http://isaac.cedarswampstudios.org/2007/HIntegerByInt OzHaskell: Australian Haskell Programmers Group. Manuel Chakravarty [17]started organising OzHaskell, and Australian Haskell user's group. 17. http://article.gmane.org/gmane.comp.lang.haskell.cafe/28883 Israeli Haskell Programmers Group. B K [18]also seeks to form an Israeli Haskell user's group 18. http://article.gmane.org/gmane.comp.lang.haskell.cafe/28877 xmonad 0.3. Don Stewart [19]announced the 0.3 release of [20]xmonad. xmonad is a tiling window manager for X. Windows are arranged automatically to tile the screen without gaps or overlap, maximising screen use. 19. http://article.gmane.org/gmane.comp.lang.haskell.cafe/28425 20. http://xmonad.org/ HPDF 1.0. alpheccar [21]announced version 1.0 of the [22]HPDF library. 21. http://article.gmane.org/gmane.comp.lang.haskell.cafe/28371 22. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/HPDF-1.0 pcap: user-level network packet capture. Bryan O'Sullivan [23]announced the release of pcap 0.3.1 23. http://article.gmane.org/gmane.comp.lang.haskell.cafe/28139 Gtk2Hs Tutorial. Hans van Thiel [24]announced a port of the GTK2 [25]tutorial by Tony Gail and Ian Main to Haskell's gtk2hs. 24. http://article.gmane.org/gmane.comp.lang.haskell.cafe/27954 25. http://tinyurl.com/yrbtsu An efficient lazy suffix tree library. Bryan O'Sullivan [26]posted a [27]suffix tree library to hackage. It implements Giegerich and Kurtz's lazy construction algorithm, with a few tweaks for better performance and resource usage. 26. http://article.gmane.org/gmane.comp.lang.haskell.cafe/27891 27. http://www.serpentine.com/software/suffixtree/ Bay Area Functional Programmers. Keith Fahlgren [28]announced the formation of the [29]Bay Area Functional Programmers group. This group is for anyone using or interested in functional programming and functional programming languages, particularly strongly typed languages such as Haskell, OCaml and SML. 28. http://article.gmane.org/gmane.comp.lang.haskell.cafe/27860 29. http://bayfp.org/ Haskell irc channel reaches 400 users. Don Stewart [30]noticed that, five and a half years after its inception, under the guiding hand of Shae Erisson (aka shapr), the [31]Haskell IRC channel on freenode has reached 400 users! 30. http://article.gmane.org/gmane.comp.lang.haskell.cafe/27826 31. http://www.haskell.org/haskellwiki/IRC_channel Guihaskell and PropLang 0.1. Asumu Takikawa [32]announced the results of his Google Summer of Code project: Guihaskell, a graphical REPL using PropLang and work on PropLang, a GUI library built on Gtk2hs that allows for high level design. 32. http://article.gmane.org/gmane.comp.lang.haskell.cafe/27598 HAppS-Data 0.9: XML, Pairs, HList, deriveAll. Alex Jacobson [33]announced that the components of [34]HAppS are being released as individual useful packages. HAppS-Data is the first in a series, and provides useful operations on XML data. 33. http://article.gmane.org/gmane.comp.lang.haskell.cafe/27597 34. http://happs.org/ Introduction to proving Haskell code. Tim Newsham [35]put together [36]a small intro lesson on proving Haskell code using quickcheck, equational reasoning and Isabelle/HOL. 35. http://article.gmane.org/gmane.comp.lang.haskell.cafe/27523 36. http://www.thenewsh.com/%7Enewsham/formal/reverse/ Very Fast Searching of ByteStrings. Chris Kuklewicz [37]announced a Boyer-Moore algorithm implemented for strict and lazy bytestrings (and combinations thereof). It finds all the overlapping instances of the pattern inside the target. 37. http://article.gmane.org/gmane.comp.lang.haskell.libraries/7363 Infinity 0.1. Austin Seipp [38]announced Infinity v0.1. an IRC bot in the essence of lambdabot; that is, it should be extendable through plugins and plugins should be easy to write, modify and contribute. 38. http://article.gmane.org/gmane.comp.lang.haskell.cafe/27445 Haskell' This section covers the [39]Haskell' standardisation process. * [40]Instances of Read on bounded integral types should detect overflow 39. http://hackage.haskell.org/trac/haskell-prime 40. http://article.gmane.org/gmane.comp.lang.haskell.prime/2302 Libraries This week's proposals and extensions to the [41]standard libraries. * [42]Add &&& and *** to Data.Tuple * [43]Add System.Info.isWindows * [44]Make arrays safer * [45]GenT monad transformer variant of Gen * [46]Test.HUnit documentation * [47]Data.List.groupBy with non-transitive equality predicate * [48]Add dropped STM invariants functions * [49]Add Data.Eq.equating to match Data.Ord.comparing * [50]Fix abstract unix sockets 41. http://haskell.org/haskellwiki/Library_submissions 42. http://thread.gmane.org/gmane.comp.lang.haskell.libraries/7550 43. http://thread.gmane.org/gmane.comp.lang.haskell.libraries/7261 44. http://thread.gmane.org/gmane.comp.lang.haskell.libraries/7283 45. http://article.gmane.org/gmane.comp.lang.haskell.libraries/7294 46. http://article.gmane.org/gmane.comp.lang.haskell.libraries/7394 47. http://article.gmane.org/gmane.comp.lang.haskell.libraries/7400 48. http://article.gmane.org/gmane.comp.lang.haskell.libraries/7598 49. http://article.gmane.org/gmane.comp.lang.haskell.libraries/7594 50. http://article.gmane.org/gmane.comp.lang.haskell.libraries/7544 Hackage This week's new libraries in [51]the Hackage library database. 51. http://hackage.haskell.org/ * numbers-2007.9.23. Lennart Augustsson. [52]numbers: instances of the numerical classes for a variety of different numbers. 52. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/numbers-2007.9.23 * hmp3 1.3. Don Stewart. [53]hmp3: An mp3 player with a curses frontend. 53. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/hmp3-1.3 * utf-string 0.2. Eric Mertens. [54]utf8-string: A UTF8 layer for IO and Strings. 54. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/utf8-string-0.2 * hstats 0.1. Marshall Beddoe. [55]hstats: A library of commonly used statistical functions. 55. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/hstats-0.1 * sparsecheck 0.2. Matthew Naylor. [56]SparseCheck: a library for logic programming in Haskell that allows convenient description of test-data generators. 56. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/sparsecheck-0.1 * monadLib 3.3.0. Iavor Diatchki. [57]monadLib: A collection of monad transformers. 57. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/monadLib-3.3.0 * ListLike 1.0.0. John Goerzen. [58]ListLike: Generic support for list-like structures in Haskell. 58. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/ListLike-1.0.0 * cabal-test 0.1. David Himmelstrup. [59]cabal-test: Cabal-test is a tool for testing cabal projects. 59. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/cabal-test-0.1 * HPDF 1.1. alpheccar. [60]HPDF: a PDF library. 60. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/HPDF-1.1 * hxt 7.3. Uwe Schmidt. [61]hxt: The Haskell XML Toolbox. 61. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/hxt-7.3 * irc 0.1. Trevor Elliott. [62]irc: A small library for parsing IRC messages 62. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/irc-0.1 * hsdns 1.0. Peter Simons. [63]hsdns: an asynchronous DNS resolver based on GNU ADNS. 63. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/hsdns-1.0 * streamproc 1.0. Peter Simons. [64]streamproc: Stream Processer Arrow 64. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/streamproc-1.0 * hsemail 1.0. Peter Simons. [65]hsemail: Parsers for the syntax defined in RFC2821 and 2822 65. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/hsemail-1.0 * funcmp 1.0. Peter Simons. [66]funcmp: Functional MetaPost is a Haskell frontend to the MetaPost language 66. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/funcmp-1.0 * cabal-rpm 0.3.1. Bryan OSullivan. [67]cabal-rpm: This package turns Haskell Cabal source packages into source and binary RPM packages. 67. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/cabal-rpm-0.3.1 * Finance-Quote-Yahoo 0.3. Brad Clawsie. [68]Finance-Quote-Yahoo: Obtain quote data from finance.yahoo.com 68. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/Finance-Quote-Ya… * xmonad 0.3. Spencer Janssen. [69]xmonad: a minimalist tiling window manager for X 69. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/xmonad-0.3 * hint 0.1. Daniel Gorin. [70]hint: an interpreter monad for Haskell expressions based on ghc-api 70. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/hint-0.1 * ipprint 0.2. Gleb Alexeyev. [71]ipprint: Tiny helper for pretty-printing values in ghci console 71. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/ipprint-0.2 * pandoc 0.44. John MacFarlane. [72]pandoc: Conversion between markup formats 72. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/pandoc-0.44 * X11-extras 0.3. Spencer Janssen. [73]X11-extras: Missing bindings to the X11 graphics library 73. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/X11-extras-0.3 * dsp 0.2. Matthew Donadio. [74]dsp: Digital Signal Processing, Fourier Transform, Filter design, Frequency estimation, Interpolation, Linear Algebra, Polynomials 74. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/dsp-0.2 * c2hs 0.15.0. Manuel Chakravarty. [75]c2hs: C->Haskell assists in the development of Haskell bindings to C libraries. 75. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/c2hs-0.15.0 * regex-base 0.92. Chris Kuklewicz. [76]regex-base: Interface API for regex-posix,pcre,parsec,tdfa,dfa 76. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/regex-base-0.92 * soegtk 0.9.12.2. Duncan Coutts. [77]soegtk: SOE api for gtk2hs 77. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/soegtk-0.9.12.2 * hsns 0.5.3. Austin Seipp. [78]hsns: a miniature network sniffer 78. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/hsns-0.5.3 * anydbm 1.0.4. John Goerzen. [79]anydbm: Interface for DBM-like database systems 79. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/anydbm-1.0.4 * suffixtree 0.2.1. Bryan O'Sullivan [80]suffixtree: An efficient, lazy suffix tree implementation. 80. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/suffixtree-0.2.1 Discussion A regressive view of support for imperative programming in Haskell. Paul Hudak [81]sparked an interesting thread about the effect on the language of rich support for imperative programming. 81. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/27214 Conference roundup * [82]Sydney Area Programming Language INterest Group: Call for Abstracts 82. http://article.gmane.org/gmane.comp.lang.haskell.cafe/29046 Jobs A top tier Investment bank is looking for a Haskell developer. Kyle McBeath [83]announced that there is a available a permanent position in London, joining a cross asset team. You will be able to use Haskell commercially everyday, be generously compensated and be on the forefront of technology in banking. This is a great opportunity for PhD students or above with proven experience of Haskell programming. 83. http://article.gmane.org/gmane.comp.lang.haskell.general/15552 Postdoctoral Fellowship in Functional Programming. Graham Hutton [84]announced that applications are invited for a 3-year postdoctoral research fellowship in functional programming, to work on the EPSRC-funded project 'Reasoning About Exceptions and Interrupts'. 84. http://article.gmane.org/gmane.comp.lang.haskell.general/15600 Blog noise [85]Haskell news from the [86]blogosphere. * [87]Peano induction for binary numbers * [88]Simple proof of stack correctness for a tiny language (in Agda) * [89]Peano, episode 3 * [90]Proving Haskell programs correct with QuickCheck and Isabelle/HOL * [91]Coq and simple group theory * [92]Coq and The Monad Laws: Introduction * [93]Coq and The Monad Laws: The First and Second * [94]Coq and The Monad Laws: The Third * [95]Revisiting board-building in chess * [96]Monads * [97]A Monad Tutorial for Ocaml * [98]Learning about (Computational) Monads * [99]I Wasn't Joking about One-Argument Haskell Functions * [100]Mapping Programming Language IRC Channels 85. http://planet.haskell.org/ 86. http://haskell.org/haskellwiki/Blog_articles 87. http://sneezy.cs.nott.ac.uk/fplunch/weblog/?p=70 88. http://sneezy.cs.nott.ac.uk/fplunch/weblog/?p=71 89. http://sneezy.cs.nott.ac.uk/fplunch/weblog/?p=72 90. http://www.thenewsh.com/%7Enewsham/formal/reverse/ 91. http://blog.mikael.johanssons.org/archive/2007/08/coq-and-simple-group-theo… 92. http://sequence.complete.org/node/358 93. http://sequence.complete.org/node/359 94. http://sequence.complete.org/node/360 95. http://sequence.complete.org/node/361 96. http://www.bofh.org.uk/articles/2007/08/07/monads 97. http://enfranchisedmind.com/blog/archive/2007/08/06/307 98. http://dailykibitz.blogspot.com/2007/08/learning-about-computational-monads… 99. http://www.oreillynet.com/onlamp/blog/2007/08/i_wasnt_joking_about_oneargum… 100. http://chneukirchen.org/blog/archive/2007/08/mapping-programming-language-i… * [101]ASCII Rave in Haskell * [102]Today is similar to the programming languages situation of twenty years ago * [103]Haskell - the videos * [104]QuickCheck : Why Testing code should be Laissez-faire * [105]Rationals! * [106]Grass-Roots Functional Languages? * [107]Programming in C, ummm, Haskell * [108]And what about C arrays? * [109]Real Quicksort in Haskell * [110]Pointer tagging * [111]n00b Thoughts on Haskell * [112]'The way forward involves functional programming' * [113]Does Syntax Matter? * [114]A bright future: security and modern type systems * [115]Making the transition from sequential to implicit parallel programming: How sequential languages obscure parallelism * [116]Software Transactional Memory - Making multithreading easier * [117]Roman Numerals in Haskell * [118]A history of monad tutorials * [119]Java Becoming Solution for Safety-Critical Applications * [120]Dunno (about STM) 101. http://doc.gold.ac.uk/~ma503am/alex/asciirave 102. http://pinderkent.blogsavy.com/archives/97 103. http://www.elbeno.com/blog/?p=353 104. http://disparatemathematician.blogspot.com/2007/08/why-testing-code-should-… 105. http://byorgey.wordpress.com/2007/08/13/rationals/ 106. http://www.falvotech.com/blog/index.php?/archives/68-Grass-Roots-Functional… 107. http://augustss.blogspot.com/2007/08/programming-in-c-ummm-haskell-heres.ht… 108. http://augustss.blogspot.com/2007/08/what-about-arrays-after-doing-my-littl… 109. http://augustss.blogspot.com/2007/08/quicksort-in-haskell-quicksort-is.html 110. http://community.livejournal.com/evan_tech/229988.html 111. http://dumpendebat.net/2007/08/14/n00b-thoughts-on-haskell/ 112. http://notes-on-haskell.blogspot.com/2007/08/haskell-more-than-just-hype.ht… 113. http://notes-on-haskell.blogspot.com/2007/08/does-syntax-matter.html 114. http://blog.moertel.com/articles/2007/08/15/a-bright-future-security-and-mo… 115. http://www.embedded.com/design/multicore/201500267 116. http://weblogs.asp.net/ralfw/archive/2007/07/03/software-transactional-memo… 117. http://fawcett.blogspot.com/2007/08/roman-numerals-in-haskell.html 118. http://koweycode.blogspot.com/2007/08/history-of-monad-tutorials.html 119. http://www.sdtimes.com/article/latestnews-20070815-04.html 120. http://patricklogan.blogspot.com/2007/08/dunno.html * [121]A thesis about language niches * [122]Thoughts on Scheme from a Haskeller * [123]Arrow Transformers for sample rate conversion * [124]Playing with Propositional Logic in Haskell * [125]Programmer productivity, feature set implementation, and runtime performance * [126]Anatomy of a new monad * [127]Welcome to Haskell for Maths Blog * [128]Monadic Parser Combinators using C# 3.0 * [129]Blog Rewrite - I'm giving up * [130]Implementing The Kelly Criterion * [131]Universal Floating Point Errors * [132]Polyglot Programming - is it all Greek to you? * [133]Factor with a dash of curry * [134]How to learn to program * [135]I dated Haskell Curry's daughter * [136]Importance and Prominence and the wave: FP * [137]A Beautiful Regex Matcher... In Haskell * [138]San Francisco Bay Area FP Group * [139]AngloHaskell: The Aftermath * [140]Leibniz Equality, Decomposition, and Definability 121. http://utcc.utoronto.ca/~cks/space/blog/programming/LanguageNiches 122. http://overwatering.blogspot.com/2007/08/thoughts-on-scheme.html 123. http://www.blurty.com/users/claudiusmaximus/day/2007/08/18 124. http://www.present-tense.org/2007/08/18/playing-with-propositional-logic/ 125. http://pinderkent.blogsavy.com/archives/107 126. http://paulspontifications.blogspot.com/2007/08/anatomy-of-new-monad.html 127. http://polyomino.blogspot.com/2007/08/welcome.html 128. http://blogs.msdn.com/lukeh/archive/2007/08/19/monadic-parser-combinators-u… 129. http://lukeplant.me.uk/blog.php?id=1107301674 130. http://r6.ca/blog/20070820T175938Z.html 131. http://notes-on-haskell.blogspot.com/2007/08/universal-floating-point-error… 132. http://grahamis.com/blog/2007/08/21/polyglot-programming-is-it-all-greek-to… 133. http://useless-factor.blogspot.com/2007/08/factors-curry.html 134. http://madhadron.auditblogs.com/2007/08/21/how-to-learn-to-program/ 135. http://importantshock.wordpress.com/2007/08/21/haskell-curry-yes-i-dated-hi… 136. http://balasubramanians.com/blog/?p=312 137. http://www.oreillynet.com/onlamp/blog/2007/08/a_beautiful_regex_matcher_in_… 138. http://kfahlgren.com/blog/2007/08/21/san-francisco-bay-area-fp-group/ 139. http://neilmitchell.blogspot.com/2007/08/anlgohaskell-aftermath.html 140. http://blog.jbapple.com/2007/08/leibniz-equality-decomposition-and.html * [141]Word ladder in Haskell * [142]Existential Data Constructors in Haskell and Qi * [143]Sun slots transactional memory into Rock * [144]Haskell for pluggable apps, with the GHC API * [145]Yoda Speaks Haskell: A Tutorial * [146]Haskell Syntax Gem * [147]ClusterBy: a handy little function for the toolbox * [148]Squarefree numbers in Haskell * [149]Overloading functional references * [150]Haskell PDF 1.0 * [151]More fun with randoms * [152]Learn Haskell in 5 minutes a day: lesson 1 * [153]Destructive Quicksort in Haskell * [154]Tries and their derivatives * [155]Haskell HMAC * [156]Solving the word numbers problem: part 2 * [157]Solving the word numbers problem: part 3 * [158]Functional Forth * [159]F#'s monadic syntax * [160]The Actors Model and Haskell 141. http://gbacon.blogspot.com/2007/08/word-ladder-in-haskell.html 142. http://programmingkungfuqi.blogspot.com/2007/08/existential-data-constructo… 143. http://www.theregister.com/2007/08/21/sun_transactional_memory_rock/ 144. http://austin.youareinferior.net/?q=node/29 145. http://www.kirit.com/Yoda%20speaks%20Visual%20Haskell 146. http://www.joachim-breitner.de/blog/archives/262-Haskell-Syntax-Gem.html 147. http://blog.moertel.com/articles/2007/09/01/clusterby-a-handy-little-functi… 148. http://byorgey.wordpress.com/2007/09/01/squarefree-numbers-in-haskell/ 149. http://twan.home.fmf.nl/blog/haskell/overloading-functional-references.deta… 150. http://www.alpheccar.org/en/posts/show/80 151. http://osfameron.vox.com/library/post/more-random-fun.html 152. http://learnhaskell.blogspot.com/2007/09/lesson-1-hello-world.html 153. http://jputnam.livejournal.com/42065.html 154. http://sigfpe.blogspot.com/2007/09/tries-and-their-derivatives_08.html 155. http://scsibug.com/2007/09/16/haskell-hmac/ 156. http://conway.rutgers.edu/~ccshan/wiki/blog/posts/WordNumbers2/ 157. http://conway.rutgers.edu/~ccshan/wiki/blog/posts/WordNumbers3/ 158. http://wiki.forthfreak.net/index.cgi?FunForth 159. http://blogs.msdn.com/dsyme/archive/2007/09/22/some-details-on-f-computatio… 160. http://lstephen.wordpress.com/2007/09/08/the-actors-model-and-haskell/ * [161]Haskell and the South African Computing Olympiad * [162]The Power of Folds * [163]Folding Incremental Averages in Haskell * [164]OpenGL tetris in Haskell * [165]Learn Haskell in 5 minutes a day: Lesson 1: Hello, World! * [166]Learn Haskell in 5 minutes a day: Lesson 2: Input and Output, Variable Binding, and more * [167]Learn Haskell in 5 minutes a day: Lesson 3: case * [168]Break a string into groups of characters * [169]A news aggregator * [170]Haskell elevator pitch * [171]Do Notation and Sequence Operator * [172]Part 1: How sequential languages obscure parallelism * [173]Part 2: How to achieve parallel execution * [174]Part 3: Explicit parallel programming with threads and locks * [175]Part 4: Explicit parallelism: message-passing programming * [176]Part 5: Implicit parallel programming: Declarative languages * [177]Part 6: So, why aren't we using functional languages yet? * [178]More articles about multicores and multiprocessors 161. http://squing.blogspot.com/2007/09/haskelling-saco-1.html 162. http://www.sftank.net/?q=node/11 163. http://kraeutler.net/vincent/essays/Folding%20Incremental%20Averages%20in%2… 164. http://myawesomeblag.blogspot.com/2007/03/opengl-tetris-in-haskell.html 165. http://learnhaskell.blogspot.com/2007/09/lesson-1-hello-world.html 166. http://learnhaskell.blogspot.com/2007/09/lesson-2-input-and-output-variable… 167. http://learnhaskell.blogspot.com/2007/09/lesson-3-case-3.html 168. http://www.perlmonks.org/?node_id=632023 169. http://www.b7j0c.org/content/haskell-newspage.html 170. http://nickmudge.info/?post=51 171. http://nickmudge.info/?post=56 172. http://www.embedded.com/design/multicore/201500267 173. http://www.embedded.com/showArticle.jhtml?articleID=201801070 174. http://www.embedded.com/showArticle.jhtml?articleID=201802337 175. http://www.embedded.com/design/multicore/201803783?_requestid=708481 176. http://www.embedded.com/design/multicore/201804960?_requestid=708724 177. http://www.embedded.com/design/multicore/201806715 178. http://www.embedded.com/design/multicore/173400008 Quotes of the Week * nomeata: Haskell is basically Swiss: Small, Efficient, and it is fun to explore the higher parts. * Tom Moertel: In the not-too-distant future, perhaps, we might look back in amazement at the days when important security properties were neither free nor guaranteed but expensive and uncertain, underwritten only by the heroic efforts of individual programmers, struggling against impossible odds to achieve inhuman perfection. * Adam Turoff: In any case, Simon Peyton Jones is right -- the way forward involves functional programming, whether it means choosing a language like Haskell, or integrating ideas from Haskell into your language of choice. * bootslack: Once, around the time of the discovery of fire, there was a large population of people that thought mastering fire would be too difficult so they didn't. The rest of us killed them, cooked them and ate them. Code Watch Notable new features and bug fixes to the Haskell compilers. Thu Sep 6 09:19:48 PDT 2007. Norman Ramsey . [179]massive changes to add a 'zipper' representation of C-- 179. http://article.gmane.org/gmane.comp.lang.haskell.cvs.ghc/23114 Tue Aug 14 03:36:23 PDT 2007. Ben Lippmeier. Add graph coloring register allocator. Refactored linear allocator into separate liveness annotation and allocation stages. Added graph coloring allocator, use -fregs-graph to enable. New dump flags are -ddump-asm-native -- output of cmm -> native transform. -ddump-asm-liveness -- code annotated with register liveness info -ddump-asm-coalesce -- output of register move coalescing (this is a separate pass when using the coloring allocator) (this could change in the future) -ddump-asm-regalloc -- code after register allocation -ddump-asm-regalloc-stages -- blocks after each build/spill stage of coloring allocator -ddump-asm-conflicts -- a global register liveness graph in graphviz format The new register allocator will allocate some registers, but it's not quite ready for prime-time yet. The spill code generator needs some work. About the Haskell Weekly News New editions are posted to [180]the Haskell mailing list as well as to [181]the Haskell Sequence and [182]Planet Haskell. [183]RSS is also available, and headlines appear on [184]haskell.org. Headlines are available as [185]PDF. To help create new editions of this newsletter, please see the [186]contributing information. Send stories to dons at galois.com. The darcs repository is available at darcs get [187]http://www.cse.unsw.edu.au/~dons/code/hwn References 180. http://www.haskell.org/mailman/listinfo/haskell 181. http://sequence.complete.org/ 182. http://planet.haskell.org/ 183. http://sequence.complete.org/node/feed 184. http://haskell.org/ 185. http://www.cse.unsw.edu.au/~dons/code/hwn/archives/20070923.pdf 186. http://haskell.org/haskellwiki/HWN 187. http://www.cse.unsw.edu.au/~dons/code/hwn

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simple function: stack overflow in hugs vs none in ghc
by Tom Pledger 23 Sep '07

23 Sep '07

John Lask wrote: : | The following code causes a "C stack overflow" in hugs (version 20051031) | but not in ghc (version 6.6) | The point of the exercise is to process a very large file lazily, | returning the consumed and unconsumed parts (i.e. basic parser combinators). : | > sqnc p ts = let ( r, ts' ) = p ts in case r of | > Nothing -> ([],ts') | > Just x -> let (r',ts'') = (sqnc p ts') in (x:r', ts'' ) : I don't know how ghc is avoiding the stack overflow, but it looks like it's caused by strict pattern matching. The first call to sqnc wants reassurance that the second call is returning a pair (as opposed to _|_) before deciding that it's OK to return a pair. Try putting a tilde in the recursive call, to make the pattern lazy. let ~(r',ts'') = ... There's a recent thread on lazy patterns in the haskell-cafe list, too. http://www.haskell.org//pipermail/haskell-cafe/2007-September/031974.html Regards, Tom

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simple function: stack overflow in hugs vs none in ghc
by john lask 20 Sep '07

20 Sep '07

Hi hoping someone can shed some light on this: The following code causes a "C stack overflow" in hugs (version 20051031) but not in ghc (version 6.6) The point of the exercise is to process a very large file lazily, returning the consumed and unconsumed parts (i.e. basic parser combinators). The simplified (stylised example of the problem) is displayed bellow. test1 (on a large file) will succeed in ghc but fail in hugs test2 on same file will succeed in both ghc and hugs the problem appears to be retaining a hold on the unconsummed portion and returning it. maybe something to do with updating CAFS, all too subtle for me. The question: is there any changes that can be made to the code to make test1 work in hugs without changing the essence of the function. >test1 = readFile "big.dat" >>= (\x->print $ parse x) >test2 = readFile "big.dat" >>= (\x->print $ fst $ parse x) big.dat is just some large data file say 1MB. (not particularly large by todays standards!) >parse x = sqnc item x > where > > item =( \ ts -> case ts of > [] -> ( Nothing, []) > ts -> ( Just (head ts), tail ts) ) > > sqnc p ts = let ( r, ts' ) = p ts in case r of > Nothing -> ([],ts') > Just x -> let (r',ts'') = (sqnc p ts') in ( >x:r', ts'' ) _________________________________________________________________ Advertisement: Search for local singles online at Lavalife http://a.ninemsn.com.au/b.aspx?URL=http%3A%2F%2Flavalife9%2Eninemsn%2Ecom%2…

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Postdoctoral Fellowship in Functional Programming
by Graham Hutton 19 Sep '07

19 Sep '07

+--------------------------------------------------------------------+ POSTDOCTORAL RESEARCH FELLOW IN FUNCTIONAL PROGRAMMING School of Computer Science University of Nottingham, UK Applications are invited for a 3-year postdoctoral research fellowship in functional programming, to work with Dr Graham Hutton on the EPSRC-funded project "Reasoning About Exceptions and Interrupts". Most modern programming languages provide special features for detecting and managing unexpected events, in the form of exception and interrupt handling primitives. Despite their importance, the issue of provable correctness for programs involving these features has received little attention, but is particularly crucial given the difficulty of writing correct programs in this setting. The aim of this project is to address this problem within the context of modern functional programming languages such as Haskell and Epigram. Applicants for this position will require a PhD in Computer Science, and research experience in functional programming. Additional desirable attributes include experience in formal semantics, program verification, concurrency theory, or theorem provers. The successful applicant will work in collaboration with Dr Graham Hutton in the Foundations of Programming group in Nottingham, a leading centre for research on formal approaches to software construction and verification. The group currently comprises 7 academic staff, 5 research staff, and 13 PhD students. Salary will be within the range 25,134 - 32,796 pounds per year, depending on qualifications and experience. The post is available immediately, and will be offered on a fixed-term contract for 3 years. Further details regarding the position and how to apply are available from Dr Graham Hutton, http://www.cs.nott.ac.uk/~gmh. Closing date for applications: 12th October 2007. +--------------------------------------------------------------------+ | Dr Graham Hutton Email : gmh(a)cs.nott.ac.uk | | School of Computer Science | | University of Nottingham Web : www.cs.nott.ac.uk/~gmh | | Jubilee Campus, Wollaton Road | | Nottingham NG8 1BB, UK Phone : +44 (0)115 951 4220 | +--------------------------------------------------------------------+ This message has been checked for viruses but the contents of an attachment may still contain software viruses, which could damage your computer system: you are advised to perform your own checks. Email communications with the University of Nottingham may be monitored as permitted by UK legislation.

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Functor ((,) a)
by Janis Voigtlaender 19 Sep '07

19 Sep '07

Hi, the Prelude docs found via http://haskell.org/hoogle/hoodoc.cgi?module=Prelude&name=Functor&mode=class claim that there is an instance Functor ((,) a) And yet, I get (in GHC, but similarly in Hugs): Prelude> fmap (+1) (undefined,2) <interactive>:1:0: No instance for (Functor ((,) a)) arising from use of `fmap' at <interactive>:1:0-22 Possible fix: add an instance declaration for (Functor ((,) a)) In the expression: fmap ((+ 1)) (undefined, 2) In the definition of `it': it = fmap ((+ 1)) (undefined, 2) What do I have to import to get the Functor ((,) a) instance? (Of course, I can define it myself, but this is not the point.) Thanks, Janis. -- Dr. Janis Voigtlaender http://wwwtcs.inf.tu-dresden.de/~voigt/ mailto:voigt@tcs.inf.tu-dresden.de

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Update: HaL2 Videos, Second Talk: Wolfgang Jeltsch now in full length
by klaus meier 18 Sep '07

18 Sep '07

Hello, we updated the video given at HaL2 (http://iba-cg.de/haskell.html) "Second Talk: Wolfgang Jeltsch (TU Cottbus) talks about Grapefruit, a Haskell-library for the declarative description of graphic user interfaces." because the last one was accidentally truncated. Greetings, Klaus Meier

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ANNOUNCE: SparseCheck
by Matthew Naylor 18 Sep '07

18 Sep '07

Dear Haskellers, You might be interested in SparseCheck, a library for typed, depth-bounded logic programming in Haskell allowing convenient expression of test-data generators for properties with sparse domains. http://www.cs.york.ac.uk/~mfn/sparsecheck/ SparseCheck is a based on a library called LP (to be presented at the Haskell Workshop) that was developed jointly with Emil Axelsson. Matthew.

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Swapping parameters and type classes
by Andrzej Jaworski 18 Sep '07

18 Sep '07

Well, the corridors are better known for the men in power:-) Why don't leave this entry as Reception for the uninitiated and move on to Announcements and ... Curiosity? Regards, -A.J.

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PLAN-X 2008 second call for papers and demos
by Ioana Manolescu 18 Sep '07

18 Sep '07

(Apologies for cross-posting) Call for Papers and Demos ========================= PLAN-X 2008 --- Programming Language Techniques for XML ACM SIGPLAN Workshop colocated with POPL 2008 San Francisco, California, USA - 9 January 2008 http://gemo.futurs.inria.fr/events/PLANX2008/ *** *** New: Submission is now open! *** http://gemo.futurs.inria.fr/events/PLANX2008/myreview/ *** The PLAN-X 2008 workshop is the forum to present and discuss bleeding-edge research at the intersection of programming language and data base technology with an emphasis on tree-shaped data structures and their XML representation. Topics of interest are all aspects of XML processing and querying: theories, methodologies, paradigms, language designs, types, analyses, runtime aspects, implementations, tools, applications. This edition of PLAN-X is particularly interested in blending the XML processing approaches developed by the programming languages and data management communities. Expressive power and high performance are among the common goals that these communities pursue. We encourage the submission of crosscutting contributions that apply techniques from one community to problems from the other. The primary criteria for paper selection are originality, relevance, and timeliness to ensure that we can enjoy reports on ongoing and unfinished work with high potential in the workshop. Submissions =========== We seek submissions in two categories * regular papers (10 pages, 30 minutes presentation) * demo papers (4 pages, 10 minutes plenary presentation + 30 minutes slot for individual discussions shared with other demos) For details see the submission instructions on http://gemo.futurs.inria.fr/events/PLANX2008/?page=subm Important Dates =============== Submission deadline 15 October 2007 Notification 30 November 2007 Final papers due 14 December 2007 Program Committee ================= Véronique Benzaken Université de Paris-Sud 11, France Alin Deutsch University of California, San Diego, USA Wenfei Fan University of Edinburgh, UK Mary Fernandez ATT Research, USA Haruo Hosoya University of Tokyo, Japan Ralf Lämmel Universität Koblenz, Germany Sebastian Maneth National ICT and UNSW, Sydney, Australia Jim Melton Oracle Corporation, USA Michael Schwartzbach University of Aarhus, Denmark Jérôme Vouillon CNRS, France Ioana Manolescu (general chair) Gemo group, INRIA Futurs, France Peter Thiemann (program chair) University of Freiburg, Germany

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Swapping parameters and type classes
by Mads Lindstrøm 18 Sep '07

18 Sep '07

Hi all If I have this type: data Foo a b = ... and this class class Bar (x :: * -> *) where ... I can imagine two ways to make Foo an instance of Bar. Either I must "apply" the 'a' or the 'b' in (Foo a b). Otherwise it will not have the right kind. To "apply" the 'a' I can do: instance Bar (Foo a) where ... But what if I want to "apply" the 'b' ? How do I do that ? Greetings, Mads Lindstrøm

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