- Haskell - Haskell.org

GHC6.8.1 can not compile the simple example
by david yu 12 Nov '07

12 Nov '07

Link error is: [davidyu@linuxpower test]$ ghc c.hs c.o: In function `rM7_info': (.text+0xaa): undefined reference to `containerszm0zi1zi0zi0_DataziMap_lookup_closure' c.o: In function `rMd_info': (.text+0x1fa): undefined reference to `containerszm0zi1zi0zi0_DataziMap_fromList_closure' c.o: In function `sVJ_info': (.text+0xa3b): undefined reference to `__stginit_containerszm0zi1zi0zi0_DataziMap_' c.o: In function `rM7_srt': (.data+0x18): undefined reference to `containerszm0zi1zi0zi0_DataziMap_lookup_closure' c.o: In function `rMd_srt': (.data+0x60): undefined reference to `containerszm0zi1zi0zi0_DataziMap_fromList_closure' collect2: ld returned 1 exit status

2 1

Haskell Weekly News: November 11, 2007
by Don Stewart 12 Nov '07

12 Nov '07

--------------------------------------------------------------------------- Haskell Weekly News http://sequence.complete.org/hwn/20071111 Issue 67 - November 11, 2007 --------------------------------------------------------------------------- Welcome to issue 67 of HWN, a newsletter covering developments in the [1]Haskell community. This week sees the release of GHC 6.8.1, to rave reviews. There have been many reports of large performance improvements for Haskell programs, from small to large production systems. Congratulations to the GHC team for such a great release! 1. http://haskell.org/ Announcements GHC 6.8.1. Ian Lynagh [2]announced the release of GHC 6.8.1, a new major release of GHC. There have been a number of significant changes since the last major release, including: Haskell Program Coverage support, the GHCi debugger, pointer tagging in the runtime (with up to 10-15% speedups), constructor specialisation, improved optimisations and much more! The [3]full release notes are available. 2. http://article.gmane.org/gmane.comp.lang.haskell.general/15733 3. http://haskell.org/ghc/docs/6.8.1/html/users_guide/release-6-8-1.html Gtk2Hs 0.9.12.1. Duncan Coutts [4]announced version 0.9.12.1 of gtk2hs is [5]now available. gtk2hs is the standard graphics library for Haskell. 4. http://article.gmane.org/gmane.comp.lang.haskell.general/15738 5. http://haskell.org/gtk2hs/download/ Lazy SmallCheck 0.1. Matthew Naylor [6]announced Lazy SmallCheck 0.1, a library for exhaustive, demand-driven testing of Haskell programs. 6. http://article.gmane.org/gmane.comp.lang.haskell.general/15702 HDBC 1.1.3. John Goerzen [7]announced new releases of HDBC, the Haskell database connectivity kit, and its associated backends (for sqlite3, postgresql, odbc). 7. http://article.gmane.org/gmane.comp.lang.haskell.general/15729 xmobar. Andrea Rossato [8]announced the release of Xmobar-0.8, a minimalistic, text based, status bar. It was specifically designed to work with the XMonad Window Manager. 8. http://article.gmane.org/gmane.comp.lang.haskell.cafe/31465 Flymake Haskell. Daisuke Ikegami [9]announced flymake haskell, emacs bindings for interactive Haskell editing. 9. http://article.gmane.org/gmane.comp.lang.haskell.cafe/31453 network bytestring. Johan Tibbel [10]announced, strict ByteString versions of the recv/send family of functions for efficient network IO. 10. http://article.gmane.org/gmane.comp.lang.haskell.general/15645 ByteString search. Bryan O'Sullivan [11]announced a cabalised version of the fast Boyer-Moore and Knuth-Morris-Pratt string search code for ByteStrings 11. http://article.gmane.org/gmane.comp.lang.haskell.cafe/31229 Generating free theorems. Janis Voigtlaender [12]announced an improved version of the online and offline free theorems generator for Haskell 12. http://article.gmane.org/gmane.comp.lang.haskell.general/15693 hslogger4j 0.1.1. Bjorn Buckwalter [13]announced Hslogger4j, which provides handlers for hslogger (John Goerzen's Haskell logging framework) that are compatible with log4j's XMLLayout. 13. http://article.gmane.org/gmane.comp.lang.haskell.general/15707 Infinity 0.3. Austin Seipp [14]announced `infinity', an IRC bot in Haskell 14. http://article.gmane.org/gmane.comp.lang.haskell.cafe/31228 hswm. Remi Turk [15]announced the first and last release of hswm, a Haskell window manager. 15. http://article.gmane.org/gmane.comp.lang.haskell.cafe/30804 Hackage This week's new libraries in [16]the Hackage library database. 16. http://hackage.haskell.org/ * xmobar-0.8. Uploaded by Andrea Rossato. [17]xmobar, a minimalistic text based status bar * hsSqlite3-0.0.4. Uploaded by Evgeny Jukov. [18]hsSqlite3, bindings for Sqlite3 * cabal-rpm-0.3.2. Uploaded by Bryan OSullivan. [19]cabal-rpm turns Haskell Cabal source packages into source and binary RPM packages. * selenium-0.2.2. Uploaded by Aaron Tomb. [20]selenium, Haskell bindings to communicate with a Selenium Remote Control server. This package makes it possible to use Haskell to write test scripts that exercise web applications through a web browser. * HPDF-1.3. Uploaded by alpheccar. [21]HPDF. A PDF library with support for several pages, page transitions, outlines, annotations, compression, colors, shapes, patterns, jpegs, fonts, typesetting ... 17. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/xmobar-0.8 18. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/hsSqlite3-0.0.4 19. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/cabal-rpm-0.3.2 20. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/selenium-0.2.2 21. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/HPDF-1.3 * FileManip-0.3.1. Uploaded by Bryan OSullivan. [22]FileManip, a Haskell library for working with files and directories. Includes code for pattern matching, finding files, modifying file contents, and more. * stringsearch-0.2. Uploaded by Bryan OSullivan. [23]stringsearch, fast search of ByteStrings. * nano-md5-0.1. Uploaded by Don Stewart. [24]nano-md5, ByteString bindings to OpenSSL. * denominate-0.4.1. Uploaded by Calvin Smith. [25]denominate provides a main program for performing bulk file and directory renaming, using a built-in filename converter or user-defined converters. * ContArrow 0.0.2. Uploaded by Evgeny Jukov. [26]ContArrow, Control.Arrow.Transformer.Cont 22. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/FileManip-0.3.1 23. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/stringsearch-0.2 24. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/nano-md5-0.1 25. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/denominate-0.4.1 26. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/ * state 0.0.2. Uploaded by Evgeny Jukov. [27]state. State. * infinity 0.3. Uploaded by Austin Seipp. [28]infinity, a tiny, pluggable irc bot. * unix-compat 0.1.2.1. Uploaded by Duncan Coutts. [29]unix-compat, portable implementations of parts of the unix package. * Ranged-sets 0.1.1. Uploaded by Paul Johnson. [30]Ranged-sets. A ranged set is an ordered list of ranges. * IFS 0.1.1. Uploaded by alpheccar. [31]IFS, a library to describe IFS and generate PPM pictures from the descriptions 27. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/ 28. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/ 29. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/ 30. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/ 31. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/ * bktrees 0.1.3. Uploaded by Josef Svenningsson. [32]bktrees. Burhard-Keller trees provide an implementation of sets which apart from the ordinary operations also has an approximate member search, allowing you to search for elements that are of a certain distance from the element you are searching for. * pqc 0.2. Uploaded by Don Stewart. [33]pqc, a parallel batch driver for QuickCheck * strict 0.2. Uploaded by Don Stewart. [34]strict, strict data types. * HsSVN 0.2. Uploaded by PHO. [35]HsSVN, (Part of) Subversion binding for Haskell * HsHyperEstraier 0.2. Uploaded by PHO. [36]HsHyperEstraier, a HyperEstraier binding for Haskell. HyperEstraier is an embeddable full text search engine which is supposed to be independent to any particular natural languages. 32. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/ 33. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/ 34. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/ 35. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/ 36. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/ * HsOpenSSL 0.3.1. Uploaded by PHO. [37]HsOpenSSL, a (part of) OpenSSL binding for Haskell. It can generate RSA and DSA keys, read and write PEM files, generate message digests, sign and verify messages, encrypt and decrypt messages. * Finance-Quote-Yahoo 0.4. Uploaded by Brad Clawsie. [38]Finance-Quote-Yahoo, obtain quote data from finance.yahoo.com * LRU 0.1.1. Uploaded by Adam Langley. [39]LRU, an LRU data structure * base 3.0. Uploaded by Ross Paterson. [40]base, the Prelude and its support libraries, and a large collection of useful libraries ranging from data structures to parsing combinators and debugging utilities. * regex-posix 0.72.0.2. Uploaded by Duncan Coutts. [41]regex-posix, posix regex support. 37. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/ 38. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/Finance-Quote-Ya… 39. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/LRU-0.1.1 40. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/base-3.0.0.0 41. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/regex-posix-0.72… * xhtml 3000.0.2.1. Uploaded by Bjorn Bringert. [42]xhtml, combinators for producing XHTML 1.0, including the Strict, Transitional and Frameset variants. * Win32 2.1.0.0. Uploaded by Esa Ilari Vuokko. [43]Win32, a binding to part of the Win32 library * unix 2.2.0.0. Uploaded by Ross Paterson. [44]unix, POSIX functionality * time 1.1.2.0. Uploaded by Ross Paterson. [45]time, time handling. * template-haskell 2.2.0.0. Uploaded by Ross Paterson. [46]template-haskell, support for manipulating Haskell syntax trees 42. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/xhtml-3000.0.2.1 43. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/Win32-2.1.0.0 44. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/unix-2.2.0.0 45. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/time-1.1.2.0 46. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/template-haskell… * stm 2.1.1.0. Uploaded by Ross Paterson. [47]stm, software transational memory * regex-compat 0.71.0.1. Uploaded by Ross Paterson. [48]regex-compat, backwards compatible regex support * regex-base 0.72.0.1. Uploaded by Ross Paterson. [49]regex-base, regex support. * readline 1.0.1.0. Uploaded by Ross Paterson. [50]readline, an interface to the GNU readline library * random 1.0.0.0. Uploaded by Ross Paterson. [51]random, random number generation 47. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/stm-2.1.1.0 48. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/regex-compat-0.7… 49. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/regex-base-0.72.… 50. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/readline-1.0.1.0 51. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/random-1.0.0.0 * QuickCheck 1.1.0.0. Uploaded by Ross Paterson. [52]QuickCheck, automatic testing of Haskell programs * process 1.0.0.0. Uploaded by Ross Paterson. [53]process, jobs and processes * pretty 1.0.0.0. Uploaded by Ross Paterson. [54]pretty, pretty printing library. * parsec 2.1.0.0. Uploaded by Ross Paterson. [55]parsec, monadic parser combinators. * parallel 1.0.0.0. Uploaded by Ross Paterson. [56]parallel, support for parallel programming 52. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/QuickCheck-1.1.0… 53. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/process-1.0.0.0 54. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/pretty-1.0.0.0 55. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/parsec-2.1.0.0 56. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/parallel-1.0.0.0 * packedstring 0.1.0.0. Uploaded by Ross Paterson. [57]packedstring, packed strings * OpenGL 2.2.1.1. Uploaded by Ross Paterson. [58]OpenGL, binding for the OpenGL graphics system * OpenAL 1.3.1.1. Uploaded by Ross Paterson. [59]OpenAL, binding to the OpenAL cross-platform 3D audio API. * old-time 1.0.0.0. Uploaded by Ross Paterson. [60]old-time, time library. * alex 2.2. Uploaded by Simon Marlow. [61]alex is a tool for generating lexical analysers in Haskell 57. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/packedstring-0.1… 58. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/OpenGL-2.2.1.1 59. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/OpenAL-1.3.1.1 60. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/old-time-1.0.0.0 61. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/alex-2.2 * Cabal 1.2.2.0. Uploaded by Duncan Coutts. [62]Cabal is the framework for packaging Haskell software * HaXml 1.19.1. Uploaded by Malcolm Wallace. [63]HaXml, Utilities for manipulating XML documents * HDBC-odbc 1.1.3.0. Uploaded by John Goerzen. [64]HDBC-odbc, ODBC driver for HDBC * HDBC-postgresql 1.1.3.0. Uploaded by John Goerzen. [65]HDBC-postgresql is a PostgreSQL driver for HDBC * HDBC-sqlite3 1.1.3.0. Uploaded by John Goerzen. [66]HDBC-sqlite3 is a Sqlite v3 driver for HDBC 62. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/Cabal-1.2.2.0 63. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/HaXml-1.19.1 64. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/HDBC-odbc-1.1.3.0 65. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/HDBC-postgresql-… 66. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/HDBC-sqlite3-1.1… * HDBC 1.1.3. Uploaded by John Goerzen. [67]HDBC is a Haskell Database library * X11 1.3.0. Uploaded by Don Stewart. [68]X11 is a library of bindings to the X11 libraries and server * HsOpenSSL 0.3. Uploaded by Masatake Daimon. [69]HsOpenSSL, (Part of) OpenSSL binding for Haskell * Imlib 0.1. Uploaded by Cale Gibbard. [70]Imlib, Haskell binding for Imlib 2 * Stream 0.2.2. Uploaded by Wouter Swierstra. [71]Stream, a library for manipulating infinite lists. 67. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/HDBC-1.1.3 68. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/X11-1.3.0 69. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/HsOpenSSL-0.3 70. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/Imlib-0.1 71. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/Stream-0.2.2 * sat 1.0. Uploaded by AndriiZvorygin. [72]sat, CNF SATisfier * torrent 2007.10.27. Uploaded by David Himmelstrup. [73]torrent, BitTorrent file parser * bencode 0.2. Uploaded by David Himmelstrup. [74]bencode, Parser and printer for bencoded data. * SDL 0.5.1. Uploaded by David Himmelstrup. [75]SDL, binding to libSDL * NGrams 1.0. Uploaded by Justin Bailey. [76]ngrams, Simple application for calculating n-grams using Google 72. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/sat-1.0 73. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/torrent-2007.10.… 74. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/bencode-0.2 75. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/SDL-0.5.1 76. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/NGrams-1.0 Discussion Bootstrapping Haskell. Andrew Copping [77]wondered how the first Haskell compilers were bootstrapped, leading to some interesting historical details. GHC 6.8 performance. Dan Piponi [78]asked about Haskell performance for low level array manipulation, with some excellent speedups produced by GHC 6.8 77. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/31459 78. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/31314 Jobs Software Development Engineer at MSR. Don Syme announced that [79]the F Sharp team is hiring! We have two positions open right now. The first is a software development engineer specializing in Visual Studio and libraries. The second Post Calendar is a software development engineer 79. http://cs.hubfs.net/blogs/f_team/archive/2007/10/30/3900.aspx PhD position at Chalmers. John Hughes [80]announced that the Functional Programming group at Chalmers is seeking to recruit a PhD student to work on domain-specific languages embedded in Haskell for hardware design, and for programming graphics processors. PhD positions in Sweden are 'real jobs', paying a respectable salary for up to five years. 80. http://article.gmane.org/gmane.comp.lang.haskell.general/15714 Blog noise [81]Haskell news from the [82]blogosphere. * [83]Scala for bioinformatics * [84]I like Haskell a lot * [85]Haskell history * [86]Continuation Passing Style for Monads * [87]Abuse: Is it ruby? Is it Haskell? It's both! * [88]Learning Haskell? * [89]For loops in Haskell * [90]A Simple Programming Puzzle Seen Through Three Differenent Lenses 81. http://planet.haskell.org/ 82. http://haskell.org/haskellwiki/Blog_articles 83. http://tiago.org/ps/2007/10/26/scala-for-bioinformatics/ 84. http://www.noulakaz.net/weblog/2007/04/20/i-like-haskell-a-lot/ 85. http://caos.di.uminho.pt/~ulisses/blog/2007/10/27/haskell-history/ 86. http://r6.ca/blog/20071028T162529Z.html 87. http://meta-meta.blogspot.com/2007/05/abuse-is-it-ruby-is-it-haskell-its-bo… 88. http://www.dynamicdrive.com/forums/showthread.php?t=26094 89. http://osfameron.vox.com/library/post/for-loops-in-haskell.html?_c=feed-atom 90. http://thraxil.org/users/anders/posts/2007/10/30/A-Simple-Programming-Puzzl… * [91]Scala Makes Me Think * [92]Haskell Substring Function * [93]Multicore Programming and Automatic Parallelisation * [94]Spinoza SOS in Haskell * [95]Why not just use Haskell? * [96]Chain delegates (in Haskell) * [97]Parser Combinators in C * [98]Will hybrid languages like D render functional languages like Haskell, OCaml and Common Lisp irrelevant? * [99]Category Theory for the Java Programmer * [100]Benchmarking ray tracing, Haskell vs. OCaml 91. http://blog.snowtide.com/2007/10/31/scala-makes-me-think 92. http://ironmonkey.blogspot.com/2007/10/haskell-substring-function_31.html 93. http://hnr.dnsalias.net/wp/?p=31 94. http://seta07.blogspot.com/2007/10/spinoza-sos-in-haskell.html 95. http://www.hackinghat.com/index.php/c/66 96. http://thoughtspam.spaces.live.com/Blog/cns!253515AE06513617!454.entry 97. http://www.math.chalmers.se/~koen/ParserComboC/parser-combo-c.html 98. http://pinderkent.blogsavy.com/archives/141 99. http://reperiendi.wordpress.com/2007/11/03/category-theory-for-the-java-pro… 100. http://augustss.blogspot.com/2007/11/benchmarking-ray-tracing-haskell-vs.ht… * [101]Some lambda calculus examples * [102]Beautiful timetables * [103]References, Arrows and Categories * [104]Anamorphisms in Ruby * [105]Type metaprogramming in Haskell and C++ * [106]A Small Combinatorial Library 101. http://augustss.blogspot.com/2007/11/some-lambda-calculus-examples-syntax-i… 102. http://onthebalcony.wordpress.com/2007/11/11/beautiful-timetables/ 103. http://twan.home.fmf.nl/blog/haskell/References-Arrows-and-Categories.detai… 104. http://weblog.raganwald.com/2007/11/really-useful-anamorphisms-in-ruby.html 105. http://www.rubinsteyn.com/template_insanity.html 106. http://sigfpe.blogspot.com/2007/11/small-combinatorial-library.html Quotes of the Week * faxathisia: Omg! I spent 2 days writing this code and it's worked the first time I run it. Only possible with Haskell :D * anonymous: The thing is Haskell isn't suited for young people, whereas the OBJECT model of C++ is * sethg: I feel like I still dont understand comonads * fnord123: Haskell mainly helps with my C++ template coding when I'm doing money oriented programming * Tac-Tics: I get the feeling if all I ever use is the IO monad, someone here will shower me in holy monad fire and cleanse the evil from me.... leaving burn marks all over * Anton van Straaten: there's a new movement towards 'functional eating' which involves using a knife and fork (think ML) or chopsticks (Haskell ;) instead of a chainsaw. Its proponents claim that this approach is far superior, but chainsaw fans are skeptical. * SamB: what happens in the monad... stays in the monad... * Brent Yorgey: Friends don't let friends write in COBOL. * Bulat Ziganshin: It's a whole new era in low-level GHC programming 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. Headlines are available as [112]PDF. To help create new editions of this newsletter, please see the [113]contributing information. Send stories to dons at galois.com. The darcs repository is available at darcs get [114]http://code.haskell.org/~dons/code/hwn/ 107. http://www.haskell.org/mailman/listinfo/haskell 108. http://sequence.complete.org/ 109. http://planet.haskell.org/ 110. http://sequence.complete.org/node/feed 111. http://haskell.org/ 112. http://code.haskell.org/~dons/code/hwn/archives/20071111.pdf 113. http://haskell.org/haskellwiki/HWN 114. http://code.haskell.org/~dons/code/hwn/

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CMCS 2008: First call for papers
by Clemens Kupke 08 Nov '07

08 Nov '07

9th International Workshop on Coalgebraic Methods in Computer Science http://www.cwi.nl/projects/cmcs08/ Budapest, Hungary April 4-6, 2008 The workshop will be held in conjunction with the 11th European Joint Conferences on Theory and Practice of Software ETAPS 2008 March 29 - April 6, 2008 Aims and Scope During the last few years, it has become increasingly clear that a great variety of state-based dynamical systems, like transition systems, automata, process calculi and class-based systems, can be captured uniformly as coalgebras. Coalgebra is developing into a field of its own interest presenting a deep mathematical foundation, a growing field of applications and interactions with various other fields such as reactive and interactive system theory, object oriented and concurrent programming, formal system specification, modal logic, dynamical systems, control systems, category theory, algebra, and analysis. The aim of the workshop is to bring together researchers with a common interest in the theory of coalgebras and its applications. The topics of the workshop include, but are not limited to: the theory of coalgebras (including set theoretic and categorical approaches); coalgebras as computational and semantical models (for programming languages, dynamical systems, etc.); coalgebras in (functional, object-oriented, concurrent) programming; coalgebras and data types; coinductive definition and proof principles for coalgebras (with bisimulations or invariants); probabilistic systems as coalgebras; algebras versus coalgebras; coalgebraic specification and verification; coalgebras and (modal) logic; game theory in coalgebra; coalgebra and control theory (notably of discrete event and hybrid systems). The workshop will provide an opportunity to present recent and ongoing work, to meet colleagues, and to discuss new ideas and future trends. Previous workshops of the same series have been organized in Lisbon, Amsterdam, Berlin, Genova, Grenoble, Warsaw, Barcelona and Vienna. The proceedings appeared as Electronic Notes in Theoretical Computer Science (ENTCS) Volumes 11,19, 33, 41, 65.1, 82.1, 106 and 164.1. You can get an idea of the types of papers presented at the meeting by looking at the tables of contents of the ENTCS volumes from those workshops. Location CMCS 2008 will be held in Budapest on April 4-6, 2008. It will be a satellite workshop of ETAPS 2008, the European Joint Conferences on Theory and Practice of Software. Programme Committee Jiri Adamek (chair, Braunschweig), Corina Cirstea (Southampton), Neil Ghani (Nottingham), H. Peter Gumm (Marburg), Bart Jacobs (Nijmegen), Clemens Kupke (co-chair, Amsterdam), Alexander Kurz (Leicester), Ugo Montanari (Pisa), Larry Moss (Indiana), John Power (Edinburgh), Jan Rutten (Amsterdam), Lutz Schröder (Bremen), Tarmo Uustalu (Tallinn), Yde Venema (Amsterdam), Hiroshi Watanabe (Osaka). Submissions Two sorts of submissions will be possible this year: Papers to be evaluated by the programme committee for inclusion in the ENTCS proceedings: These papers must be written using ENTCS style files and be of length no greater than 20 pages. They must contain original contributions, be clearly written, and include appropriate reference to and comparison with related work. If a submission describes software, software tools, or their use, it should include all source code that is needed to reproduce the results but is not publicly available. If the additional material exceeds 5 MB, URL's of publicly available sites should be provided in the paper. Short contributions: These will not be published but will be compiled into a technical report of the Technical University of Braunschweig. They should be no more than two pages and may describe work in progress, summarise work submitted to a conference or workshop elsewhere, or in some other way appeal to the CMCS audience. Both sorts of submission should be submitted in postscript or pdf form as attachments to an email to cmcs08(a)cwi.nl. The email should include the title, corresponding author, and, for the first kind of submission, a text-only one-page abstract. After the workshop, we expect to produce a journal proceedings of extended versions of selected papers to appear in Theoretical Computer Science. Important Dates Deadline for submission of regular papers: January 13, 2008. Notification of acceptance of regular papers: February 11, 2008. Final version for the preliminary proceedings: February 18, 2008. Deadline for submission of short contributions: March 10, 2008. Notification of acceptance of short contributions: March 17, 2008. For more information, please write to cmcs08(a)cwi.nl

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ANNOUNCE: Gtk2Hs version 0.9.12.1 released
by Duncan Coutts 08 Nov '07

08 Nov '07

Gtk2Hs - A GUI Library for Haskell based on Gtk+ Version 0.9.12.1 is now available from: http://haskell.org/gtk2hs/download/ The source tarball and an installer for Windows are available. Packages for various platforms should become available soon, hopefully including Debian, Fedora, Gentoo, FreeBSD and Darwin. Changes since 0.9.12.1: * builds with GHC 6.8.1 * updated SOE API to match that of the recent SOE release * added status icon binding * added text buffer clipboard functions * fix build issue with recent glib versions * a few minor bug fixes Gtk2Hs feature highlights: * automatic memory management * Unicode support * nearly full coverage of Gtk+ 2.8 API * support for several additional Gtk+/Gnome modules: * Glade visual GUI builder * cairo vector graphics library * SVG rendering for cairo * OpenGL extension (works with HOpenGL) * GConf, Gnome's system for storing app preferences * SourceView, code editor widget with syntax highlighting * the Mozilla browser rendering engine in a widget * an implementation of the Graphics.SOE API * extensive haddock API reference documentation * multi-platform support with native look * LGPL licence Platforms and requirements: * builds from source on Linux, Windows and Solaris * should also build from source on MacOS X and FreeBSD * builds with GHC 6.4.2 - 6.8.1 * works with Gtk+ version 2.0 through to 2.10 * SVG support requires librsvg version 2.16 or later Please report all problems to gtk2hs-devel(a)sourceforge.net or in our bug tracker http://hackage.haskell.org/trac/gtk2hs Contributions and feedback are also most welcome. Windows release notes: The installer expects GHC 6.8.1 or GHC 6.6.1. Duncan (on behalf of the Gtk2Hs team)

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Garbage collection problem
by Jinping Zhang 05 Nov '07

05 Nov '07

HI,can anybody help me with the following garbage collection problem ? I'm trying to develop a test tool which can generate test data systematically for Haskell program, I have finished most of the work so far, however,while testing, the process would be interrupted because of the garbage collection problem with the notice "ERROR - Garbage collection fails to reclaim sufficient space",what shall i do to solve this problem? so that the user may test the possible input of a infinite type all the time as long as he or she wants to. By the way, the interpreter I used was Hugs98. Thank you very much. Best regards Jinping Zhang

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package maintainers: updating your packages to work with GHC 6.8.1
by Duncan Coutts 05 Nov '07

05 Nov '07

If you maintain a Haskell package this is for you. So now that GHC 6.8.1 is out you'll want to test your package with it. We'd especially like maintainers of packages that are distributed on hackage.haskell.org to test their packages and update them as necessary. However we would appreciate it if your packages will still work with GHC 6.6.x, so read below for details on how to do that. You'll most likely find that your package fails to build with GHC 6.8.1 with an error message like this: Could not find module `Data.Map': it is a member of package containers-0.1.0.0, which is hidden. This is the first symptom of the change in the base library in GHC 6.8.1. Several parts of the old base library got split out into separate packages. For example Data.Map is now in the containers package. Unfortunately this means most packages need updating. Of course you'd also like to make your packages continue to work with GHC 6.6.x (and perhaps older). If you go and just add containers to your package's build-depends then it will no longer work with GHC 6.6.x or older. So the solution at the moment is to use Cabal configurations like so: flag splitBase description: Choose the new smaller, split-up base package. library if flag(splitBase) build-depends: base >= 3, containers else build-depends: base < 3 Since this uses a new Cabal feature you'll have to make your packages require Cabal-1.2 or later: cabal-version: >=1.2 This is ok since Cabal-1.2.x comes with ghc-6.8 and can also be installed from hackage for older ghc versions. For a bigger example see Cabal's own .cabal file: http://hackage.haskell.org/packages/archive/Cabal/1.2.2.0/Cabal.cabal The new Cabal syntax is explained in the Cabal user guide: http://haskell.org/cabal/release/rc/doc/users-guide/x30.html#configurations This is all explained in more detail on the wiki: http://haskell.org/haskellwiki/Upgrading_packages And the details of other api changes in the libraries are in the GHC 6.8.1 release notes: http://haskell.org/ghc/docs/6.8.1/html/users_guide/release-6-8-1.html A list of packages on hackage that currently fail to build with GHC 6.8.1 is here: http://www.haskell.org/pipermail/libraries/2007-November/008529.html We realise that this change is rather disruptive, requiring changes in each package. We've started a wiki page with ideas on how to avoid this in future when the base package is shrunk again. http://hackage.haskell.org/trac/ghc/wiki/PackageCompatibility Duncan (Cabal release manager)

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ANNOUNCE: GHC version 6.8.1
by Ian Lynagh 03 Nov '07

03 Nov '07

============================================================= The (Interactive) Glasgow Haskell Compiler -- version 6.8.1 ============================================================= The GHC Team is pleased to announce a new major release of GHC. There have been a number of significant changes since the last major release, including: * Haskell Program Coverage (hpc) support has been added to the compiler * GHCi now includes a debugger * The first phase of the base package split has been done * The code generator now uses pointer tagging (which should mean most code improves by 10-15%, and as a result the compiler is also faster). The full release notes are here: http://haskell.org/ghc/docs/6.8.1/html/users_guide/release-6-8-1.html How to get it ~~~~~~~~~~~~~ The easy way is to go to the web page, which should be self-explanatory: http://www.haskell.org/ghc/ We supply binary builds in the native package format for many platforms, and the source distribution is available from the same place. Packages will appear as they are built - if the package for your system isn't available yet, please try again later. Background ~~~~~~~~~~ Haskell is a standard lazy functional programming language; the current language version is Haskell 98, agreed in December 1998 and revised December 2002. GHC is a state-of-the-art programming suite for Haskell. Included is an optimising compiler generating good code for a variety of platforms, together with an interactive system for convenient, quick development. The distribution includes space and time profiling facilities, a large collection of libraries, and support for various language extensions, including concurrency, exceptions, and foreign language interfaces (C, whatever). GHC is distributed under a BSD-style open source license. A wide variety of Haskell related resources (tutorials, libraries, specifications, documentation, compilers, interpreters, references, contact information, links to research groups) are available from the Haskell home page (see below). On-line GHC-related resources ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Relevant URLs on the World-Wide Web: GHC home page http://www.haskell.org/ghc/ GHC developers' home page http://hackage.haskell.org/trac/ghc/ Haskell home page http://www.haskell.org/ Supported Platforms ~~~~~~~~~~~~~~~~~~~ The list of platforms we support, and the people responsible for them, is here: http://hackage.haskell.org/trac/ghc/wiki/Contributors Ports to other platforms are possible with varying degrees of difficulty. The Building Guide describes how to go about porting to a new platform: http://hackage.haskell.org/trac/ghc/wiki/Building Developers ~~~~~~~~~~ We welcome new contributors. Instructions on accessing our source code repository, and getting started with hacking on GHC, are available from the GHC's developer's site run by Trac: http://hackage.haskell.org/trac/ghc/ Mailing lists ~~~~~~~~~~~~~ We run mailing lists for GHC users and bug reports; to subscribe, use the web interfaces at http://www.haskell.org/mailman/listinfo/glasgow-haskell-users http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs There are several other haskell and ghc-related mailing lists on www.haskell.org; for the full list, see http://www.haskell.org/mailman/listinfo/ Some GHC developers hang out on #haskell on IRC, too: http://www.haskell.org/haskellwiki/IRC_channel Please report bugs using our bug tracking system. Instructions on reporting bugs can be found here: http://www.haskell.org/ghc/reportabug

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TYPES small workshop on Effects and Type Theory
by Tarmo Uustalu 02 Nov '07

02 Nov '07

In the frame of the extended EU FP6-funded TYPES project, we are organizing an ad hoc "small workshop" on integration of effects into type-theoretic programming/reasoning. This is an informal event and attendance is not confined to people involved in TYPES. On the contrary, attendance and contributions from outside the TYPES consortium are most welcome. The invited speakers are Paul Levy and Aleksandar Nanevski. --- Call for contibutions and participation Workshop on Effects and Type Theory, EffTT Tallinn, Estonia, 13-14 December 2007 http://cs.ioc.ee/efftt/ a "small workshop" of the TYPES project Background The syntax and semantics of impurities of computation known as effects have been an important challenge for functional programming. Today, we tend to employ categorically inspired tools such as monads, Lavwere theories and arrows, but also more pragmatic approaches such as uniqueness typing. Effects are an issue also for type-theoretic programming and reasoning, where a number of aspects make them specifically interesting. First, we do not yet know what the best dependently typed generalizations of our simply typed tools are, although we hope they would reinforce the dual utility of type-theoretic calculi as programming languages and logics. Second, this duality specifically forces that pure computations must terminate, so even nontermination is an impurity and potentially an effect. Third, is it not likely that the type-theoretic glasses can help us see more clearly the particularities of external-world effects such as true destructively updatable state and true interactive input-output? Thus, this workshop is exactly about effects and type theory. Topics of interest include * all kinds of dependent generalizations of monads and more * type-theoretic language design for effects * type-theoretic effectful programming methodology * time, nontermination and type theory * state and type theory, including combinations of Hoare-like logics and type theory * interactive input-output and type theory * theories of external-world effects * type theory and concurrency * type-theoretic descriptions of physical systems * and any further topics about effects and type theory Invited speakers Our invited speakers are Paul Levy (Birmingham) and Aleksandar Nanevski (Microsoft Research, Cambridge). Contributing a talk The rest of the programme will be based on contributed talks and discussions. If you would like to contribute a talk, send a title and abstract to efftt(at)cs.ioc.ee by 21 November 2007. Organizers The workshop organizers are Thorsten Altenkirch, Marino Miculan and Tarmo Uustalu. Venue The workshop will take place in the building of the Estonian Academy of Sciences on Tallinn's Dome Hill. The workshop dates are during the Tallinn Christmas market and the Christmas Jazz festival of Jazzkaar. Participating To register, please drop an email to efftt(at)cs.ioc.ee as soon as possible, but not later than 21 November 2007. Attendance is not confined to people involved in the TYPES project; the workshop is open to anyone interested.

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Image manipulation
by Björn Wikström 01 Nov '07

01 Nov '07

Hi! I have lots and lots of images (jpegs) that I would like to manipulate and shrink (in size). They are around 5 Mb big, so I thought this would be a good Haskell project since its a lazy evaluating language. The problem is that I cant find any libraries for image manipulation. Anyone who knows something that would interest me and maybe give me some advices? Best regards, Bjorn.

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HDBC & drivers 1.1.3 released
by John Goerzen 31 Oct '07

31 Oct '07

Today I have released HDBC 1.1.3 and the HDBC backend drivers 1.1.3. Changes follow: HDBC 1.1.3 http://software.complete.org/hdbc * [API] Added strict versions of fetchAll* and related functions. Specific new functions are: quickQuery', fetchAllRows', fetchAllRowsAL', fetchAllRowsMAP', sFetchAllRows'. This does not impact database drivers. No user impact. * [API] Changed spec to make the following functions strict in their result: describeResult, getTables, describeTable. No code change in HDBC. Potential code change in backends. No anticipated user impact. * Add SqlByteString constructor to SqlValue. Patch from Toby Allsopp. HDBC-sqlite3 1.1.3.0 http://software.complete.org/hdbc-sqlite3 * Updated for new strictness in HDBC 1.1.3 * Updated Cabal file * Efficint binding of ByteString arguments. (Path from Toby Allsopp) HDBC-postgresql 1.1.3.0 http://software.complete.org/hdbc-postgresql * Strictify a few functions for 1.1.3 API * Improve metadata handling. Patch from Steve Harris * Use better SqlValue constructors for column types. Patch from Steve Harris. HDBC-odbc 1.1.3.0 http://software.complete.org/hdbc-odbc * Stricify a few functions for 1.1.3 API

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