January 2007 - Haskell

Announcing Djinn, version 2004-12-11, a coding wizard
by Lennart Augustsson 07 Apr '11

07 Apr '11

Howdy, y'all! I've written a small program that takes a (Haskell) type and gives you back a function of that type if one exists. It's kind of fun, so I thought I'd share it. It's probably best explained with a sample session. calvin% djinn Welcome to Djinn version 2005-12-11. Type :h to get help. # Djinn is interactive if not given any arguments. # Let's see if it can find the identity function. Djinn> f ? a->a f :: a -> a f x1 = x1 # Yes, that was easy. Let's try some tuple munging. Djinn> sel ? ((a,b),(c,d)) -> (b,c) sel :: ((a, b), (c, d)) -> (b, c) sel ((_, v5), (v6, _)) = (v5, v6) # We can ask for the impossible, but then we get what we # deserve. Djinn> cast ? a->b -- cast cannot be realized. # OK, let's be bold and try some functions that are tricky to write: # return, bind, and callCC in the continuation monad Djinn> type C a = (a -> r) -> r Djinn> returnC ? a -> C a returnC :: a -> C a returnC x1 x2 = x2 x1 Djinn> bindC ? C a -> (a -> C b) -> C b bindC :: C a -> (a -> C b) -> C b bindC x1 x2 x3 = x1 (\ c15 -> x2 c15 (\ c17 -> x3 c17)) Djinn> callCC ? ((a -> C b) -> C a) -> C a callCC :: ((a -> C b) -> C a) -> C a callCC x1 x2 = x1 (\ c15 _ -> x2 c15) (\ c11 -> x2 c11) # Well, poor Djinn has a sweaty brow after deducing the code # for callCC so we had better quit. Djinn> :q Bye. To play with Djinn do a darcs get http://darcs.augustsson.net/Darcs/Djinn or get http://darcs.augustsson.net/Darcs/Djinn/Djinn.tar.gz Then just type make. (You need a Haskell 98 implementation and some libraries.) And then start djinn. For the curious, Djinn uses a decision procedure for intuitionistic propositional calculus due to Roy Dyckhoff. It's a variation of Gentzen's LJ system. This means that (in theory) Djinn will always find a function if one exists, and if one doesn't exist Djinn will terminate telling you so. This is the very first version, so expect bugs. :) Share and enjoy. -- Lennart

8 13

Haskell-mode 2.0
by Stefan Monnier 02 Feb '09

02 Feb '09

I have recently taken over maintainership of Haskell-mode, and after making a bunch of changes, I figured it would be a good idea to make a new release. You can find this new release at: http://www-perso.iro.umontreal.ca/~monnier/elisp/ If you think it should also be found at http://www.haskell.org/haskell-mode/, then please tell John Peterson to get back to me (my email to him seem to go straight to the bitbucket. John?). This release has several changes that have all been only lightly tested, especially w.r.t compatibility with various Emacsen. See appended the NEWS file that describes some of the notewirthy changes. Stefan Changes since 1.45: * keybindings C-c <char> have been replaced by C-c C-<char> so as not to collide with minor modes. * The following modules are now automatically activated without having to add anything to haskell-mode-hook: haskell-font-lock (just turn on global-font-lock-mode). haskell-decl-scan (just bind `imenu' to some key). * In recent Emacsen, haskell-doc hooks into eldoc-mode. * haskell-hugs and haskell-ghci are superceded by inf-haskell. * Indentation rules have been improved when using layout inside parens/braces. * Symbols like -> and \ can be displayed as actual arrows and lambdas. See haskell-font-lock-symbols. * Tweaks to the font-lock settings. Among other things paren-matching with things like \(x,y) should work correctly now. * New maintainer <monnier(a)gnu.org>.

3 6

[Fwd: Re: Computer Language Shootout]
by Simon Marlow 27 Feb '07

27 Feb '07

Forwarding on behalf of Andrzej Jaworski <himself(a)poczta.nom.pl>: -------- Original Message -------- From: Andrzej Jaworski <himself(a)poczta.nom.pl> Dear fellows, It is ironic that just after SPJ disclosed Comments from Brent Fulgham on Haskell and the shootout the situation has radically changed for the worse. Without knowing that I committed a blunder referring to the damn benchmark http://shootout.alioth.debian.org/gp4/benchmark.php?test=all&lang=all together with multicore support arguments when trying to convert a prominent OCaml programmer to Haskell. Now they know more of us:-) What a language it is that jumps 30% up and down on benchmark while other languages gracefully stay in line? Can any of you explain the reason for this disgraceful degradation in Computer Language Shootout? Clean has also declined in these benchmarks but not that much as Haskell. According to John van Groningen Clean's binary-trees program in the previous shootout version used lazy data structure which resulted in lower memory usage and much faster execution. That was removed by the maintainer of the shootout and replaced by a much slower one using strict data structure. I fear that if laziness accounted for previous good scores of GHC then algorithms where laziness is downplayed must be responsible for that anecdotal opinion that Haskell can be extremely slow. For example: on Royal Road Problem in genetic algorithms http://www.dcs.ed.ac.uk/home/stg/sfpw/book/Garmendia-Doval/cameraready.ps Haskell was found to be on average over 500 times slower than SML implementation! If such extreme variations in performance are inherent for Haskell then the support for multicore rather than boosting its relative performance (against e.g. one-core-bound OCaml) may merely amplify Haskell unevenness to the point where programming becomes more of an art than a science like it is in Prolog. Perhaps making a collective effort towards benchmarking Haskell programs and analyzing the results in some methodic way could prove helpful? Regards, Andrzej Jaworski

14 14

ANNOUNCE: Buggy nofib
by Josep Francesc Silva Galiana 02 Feb '07

02 Feb '07

Hi, we have developed a 'buggy' version of the nofib collection of Haskell programs. All programs contain one of these bugs: - a bug that produces an incorrect result - a bug that produces non-termination - a bug that produces an exception (e.g., div by zero) Our buggy nofib suite can be used to test debugging tools. It is publicly available as a DARCS repo at http://einstein.dsic.upv.es/darcs/nofib There is also a web interface with basic search facilities at http://einstein.dsic.upv.es/nofib Any suggestion or comment is welcome! Best regards, -. Josep Silva .- DSIC - Technical University of Valencia

1 2

ANNOUNCE: binary: high performance, pure binary serialisation
by dons＠cse.unsw.edu.au 31 Jan '07

31 Jan '07

Binary: high performance, pure binary serialisation for Haskell ---------------------------------------------------------------------- The Binary Strike Team is pleased to announce the release of a new, pure, efficient binary serialisation library for Haskell, now available from Hackage: tarball: http://hackage.haskell.org/cgi-bin/hackage-scripts/package/binary/0.2 darcs: darcs get http://darcs.haskell.org/binary haddocks: http://www.cse.unsw.edu.au/~dons/binary/Data-Binary.html The 'binary' package provides efficient serialisation of Haskell values to and from lazy ByteStrings. ByteStrings constructed this way may then be written to disk, written to the network, or further processed (e.g. stored in memory directly, or compressed in memory with zlib or bzlib). Encoding and decoding are achieved by the functions: encode :: Binary a => a -> ByteString decode :: Binary a => ByteString -> a which mirror the read/show functions. Convenience functions for serialising to disk are also provided: encodeFile :: Binary a => FilePath -> a -> IO () decodeFile :: Binary a => FilePath -> IO a To serialise your Haskell data, all you need do is write an instance of Binary for your type. For example, suppose in an interpreter we had the data type: import Data.Binary import Control.Monad data Exp = IntE Int | OpE String Exp Exp We can serialise this to bytestring form with the following instance: instance Binary Exp where put (IntE i) = putWord8 0 >> put i put (OpE s e1 e2) = putWord8 1 >> put s >> put e1 >> put e2 get = do tag <- getWord8 case tag of 0 -> liftM IntE get 1 -> liftM3 OpE get get get The binary library has been heavily tuned for performance, particularly for writing speed. Throughput of up to 160M/s has been achieved in practice, and in general speed is on par or better than NewBinary, with the advantage of a pure interface. Efforts are underway to improve performance still further. Plans are also taking shape for a parser combinator library on top of binary, for bit parsing and foreign structure parsing (e.g. network protocols). Several projects are using binary already for serialisation: lambdabot : state file serialisation hmp3 : mp3 file database hpaste.org : pastes are stored in memory as compressed bytestrings, and serialised to disk on MACID checkpoints Binary was developed by a team of 8 during the Haskell Hackathon, Hac 07, and received 200+ commits over that period. You can see the commit graph here: http://www.cse.unsw.edu.au/~dons/images/commits/community/binary-commits.png The use of QuickCheck was critical to the rapid, safe development of the library. The API was developed in conjunction with the QuickCheck properties that checked the API for sanity. We were thus able to improve performance while maintaining stability. We feel that QuickCheck should be an integral part of the development strategy for all new Haskell libraries. Don't write code without it! Binary is portable, using the foreign function interface and cpp, and is tested with Hugs and GHC. Happy hacking! The Binary Strike Team, Lennart Kolmodin Duncan Coutts Don Stewart Spencer Janssen David Himmelstrup Bjorn Bringert Ross Paterson Einar Karttunen

4 4

ANNOUNCE: The Monad.Reader - Issue 6
by Wouter Swierstra 31 Jan '07

31 Jan '07

Dear all, I pleased to announce that the latest issue of The Monad.Reader is now available: http://www.haskell.org/haskellwiki/The_Monad.Reader Issue 6 consists of the following three articles: * Bernie Pope - Getting a Fix from the Right Fold * Dan Piponi - Adventures in Classical-Land * Russell O'Connor - Assembly: Circular Programming with Recursive do The Monad.Reader is a quarterly magazine about all things Haskell. It is less-formal than journal, but somehow more enduring than a wiki- page or blog post. If you'd like to submit something to the next issue of The Monad.Reader, please get in touch. The preliminary deadline for Issue 7 is March 30, 2007. I will send out an official call for copy in the coming weeks. For now, enjoy Issue 6! Wouter 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.

2 1

Correction: TFP 2007 Submission Deadline is Tomorrow
by TFP 2007 31 Jan '07

31 Jan '07

Dear Colleagues, Apologies in advance for the "p.m." ommission. This is a kind reminder that the deadline for extended abstract submissions to TFP 2007 is tomorrow, Feb. 1 at 11:59 p.m. EST. We are also pleased to announce that the TFP 2007 invited speaker is John McCarthy, Stanford University. For further details, please visit our website at: http://cs.shu.edu/tfp2007/ . The TFP 2007 program committee looks forward to receiving your submissions! Best wishes, Marco ************************************************************************************ Dr. Marco T. Morazan TFP 2007 Program Committee Chair http://cs.shu.edu/tfp2007/

1 0

TFP 2007 Submission Deadline is Tomorrow
by TFP 2007 31 Jan '07

31 Jan '07

Dear Colleagues, This is a kind reminder that the deadline for extended abstract submissions to TFP 2007 is tomorrow, Feb. 1 at 11:59 EST. We are also pleased to announce that the TFP 2007 invited speaker is John McCarthy, Stanford University. For further details, please visit our website at: http://cs.shu.edu/tfp2007/ . The TFP 2007 program committee looks forward to receiving your submissions! Best wishes, Marco ************************************************************************************ Dr. Marco T. Morazan TFP 2007 Program Committee Chair http://cs.shu.edu/tfp2007/

1 0

Haskell Weekly News: January 31, 2007
by dons＠cse.unsw.edu.au 31 Jan '07

31 Jan '07

--------------------------------------------------------------------------- Haskell Weekly News http://sequence.complete.org/hwn/20070131 Issue 57 - January 31, 2007 --------------------------------------------------------------------------- Welcome to issue 57 of HWN, a weekly newsletter covering developments in the [1]Haskell community. Lots of news to report after a break due to Hac '07 and POPL. 1. http://haskell.org/ Announcements lhs2tex 1.12. Andres Loeh [2]announced lhs2TeX version 1.12, a preprocessor to generate LaTeX code from literate Haskell sources. [3]lhs2TeX includes the following features: highly customized output; liberal parser; generate multiple versions of a program or document from a single source; active documents: call Haskell to generate parts of the document (useful for papers on Haskell); a manual explaining all the important aspects of lhs2TeX. 2. http://article.gmane.org/gmane.comp.lang.haskell.general/14733 3. http://www.iai.uni-bonn.de/~loeh/lhs2tex/ hscom. Krasimir Angelov [4]announced the [5]hscom library. This is a FFI library for Microsoft COM. It is far from complete and it doesn't have automatic IDL to Haskell translator but if you have ever thought to start writing you own COM library for Haskell then please take a look. It is designed to be as close as possible to the standard FFI library for C. 4. http://article.gmane.org/gmane.comp.lang.haskell.general/14743 5. http://darcs.haskell.org/packages/hscom/ DeepArrow 0.0: Arrows for 'deep application'. Conal Elliott [6]announced the birth of [7]DeepArrow, a Haskell library for composable 'editors' of pure values. DeepArrow enables 'deep function application' in two senses: deep application of functions and application of deep functions. These tools generalize beyond values and functions, via the DeepArrow subclass of the Arrow type class. 6. http://article.gmane.org/gmane.comp.lang.haskell.general/14753 7. http://haskell.org/haskellwiki/DeepArrow Phooey 0.1: functional user interface library. Conal Elliott [8]announced version 0.1 of [9]Phooey, an arrow-based functional user interface library. New in version 0.1: documentation, text input, boolean input/output, mtl. Phooey is now used in [10]TV. 8. http://article.gmane.org/gmane.comp.lang.haskell.general/14754 9. http://haskell.org/haskellwiki/phooey 10. http://haskell.org/haskellwiki/TV TV 0.0: Tangible Values. Conal Elliott [11]announced TV, a library for composing tangible values (TVs): values that carry along external interfaces. In particular, TVs can be composed to create new TVs, and they can be directly executed with a friendly GUI, a process that reads and writes character streams, or many other kinds interfaces. Values and interfaces are combined for direct use, and separable for composability. [12]See the project page. 11. http://article.gmane.org/gmane.comp.lang.haskell.general/14755 12. http://haskell.org/haskellwiki/TV polyparse 1.00. Malcolm Wallace [13]announced the release of [14]PolyParse, a collection of parser combinator libraries in Haskell. They were all previously distributed as part of HaXml, but are now split out to make them more widely available. 13. http://article.gmane.org/gmane.comp.lang.haskell.general/14777 14. http://www.cs.york.ac.uk/fp/polyparse Data.Binary: binary serialisation. The Binary Strike Force [15]announced the release of [16]Binary, a high performance, pure binary serialisation library for Haskell. It is available from [17]Hackage and [18]darcs. The 'binary' package provides efficient serialisation of Haskell values to and from lazy ByteStrings. ByteStrings constructed this way may then be written to disk, written to the network, or further processed (e.g. stored in memory directly, or compressed in memory with zlib or bzlib). 15. http://article.gmane.org/gmane.comp.lang.haskell.general/14800 16. http://www.cse.unsw.edu.au/~dons/binary/Data-Binary.html 17. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/binary/0.2 18. http://darcs.haskell.org/binary DrIFT 2.2.1: support for Data.Binary. John Meacham [19]announced that [20]DrIFT 2.2.1 is out and now has support for the Data.Binary module. 19. http://article.gmane.org/gmane.comp.lang.haskell.general/14802 20. http://repetae.net/~john/computer/haskell/DrIFT/ A History of Haskell. Simon Peyton-Jones [21]mentioned that the paper 'A History of Haskell: being lazy with class', authored by Paul Hudak, John Hughes, Phil Wadler and Simon, is finally done. [22]You can get a copy now! 21. http://article.gmane.org/gmane.comp.lang.haskell.general/14793 22. http://research.microsoft.com/~simonpj/papers/history-of-haskell/index.htm piggybackGHC 0.1. Martin Grabmueller [23]announced the release 0.1 of [24]piggybackGHC, a small utility package for using GHC for lexing and parsing Haskell source code. The library uses the GHC library for all the hard stuff, so all supported GHC extensions are available. 23. http://article.gmane.org/gmane.comp.lang.haskell.cafe/18461 24. http://uebb.cs.tu-berlin.de/~magr/projects/piggybackGHC/doc/ regex-tdfa 0.20. Chris Kuklewicz [25]announced regex-tdfa, a 'tagged' DFA regular expression backend in pure Haskell, along with a suite of updates to the existing regex packages. 25. http://article.gmane.org/gmane.comp.lang.haskell.cafe/18553 hpaste.org. Eric Mertens [26]announced 'hpaste', the [27]Haskell Pastebin. Developed over a few days by many of the members of the Haskell irc channel, it provies a reliable paste bot with Haskell-specific capabilities. 26. http://article.gmane.org/gmane.comp.lang.haskell.cafe/18565 27. http://hpaste.org/ Haskell' This section covers the [28]Haskell' standardisation process. * [29]Views in Haskell * [30]Pattern guards * [31]Help from the community * [32]Polymorphic Components 28. http://hackage.haskell.org/trac/haskell-prime 29. http://thread.gmane.org/gmane.comp.lang.haskell.general/14766 30. http://thread.gmane.org/gmane.comp.lang.haskell.prime/1992 31. http://thread.gmane.org/gmane.comp.lang.haskell.prime/2002/focus=2026 32. http://thread.gmane.org/gmane.comp.lang.haskell.prime/2002 Libraries This week's proposals and extensions to the [33]standard libraries. * [34]Splitting up the crypto package * [35]Cofunctors * [36]System.Timeout module for base * [37]Unsafe aspects of ByteString * [38]Add Data.String containing IsString(fromString) to base * [39]Make StateT in mtl lazy 33. http://haskell.org/haskellwiki/Library_submissions 34. http://article.gmane.org/gmane.comp.lang.haskell.libraries/6108 35. http://article.gmane.org/gmane.comp.lang.haskell.libraries/6108 36. http://thread.gmane.org/gmane.comp.lang.haskell.libraries/6144 37. http://thread.gmane.org/gmane.comp.lang.haskell.libraries/6152 38. http://thread.gmane.org/gmane.comp.lang.haskell.libraries/6172 39. http://thread.gmane.org/gmane.comp.lang.haskell.libraries/6174 Discussion Beautiful concurrency. Simon Peyton-Jones [40]announced that the revised draft of 'Beautiful concurrency' is now [41]online, and feedback is welcome. 40. http://article.gmane.org/gmane.comp.lang.haskell.general/14739 41. http://haskell.org/haskellwiki/Talk:SantaClausProblemV2 Even higher-order abstract syntax: typeclasses vs GADT. Oleg Kiselyov [42]demonstrated a typeclass implementation of the canonical use case for GADTs: a higher-order abstract-syntax-based embedding of a language in Haskell, with implement static and dynamic semantics of the language. The interpreter of the language is tagless and statically assured: only well-typed terms may be evaluated, and the evaluation of those does not get stuck. 42. http://article.gmane.org/gmane.comp.lang.haskell.general/14764 JHC call for volunteers. John Meacham [43]mentioned that Jhc has recently gotten a ghc back end, making it much closer to mainstream use as an optimizing 'front end' to ghc. In addition to some of jhc's crazy optimizations, it implements several extensions to the language which will likely prove interesting to play with to some. John would like to welcome any volunteers who would like to help develop the ghc back end while I work on improving the grin back end and optimizations in general, to make JHC a viable alternative compiler for Haskell. 43. http://article.gmane.org/gmane.comp.lang.haskell.general/14798 State monad strictness. Yitzchak Gale [44]pondered strictness in State monads. 44. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/18276 Using PAPI to measure performance with CPU events. Alexey Yakushev [45]described how to use the new PAPI library together with GHC to gather performance information from your CPU (cache misses, branch misprediction). At present only cache miss information is supported in a platform independent way (though not tested). Also, this implementation separates the performance information for the garbage collector and the mutator so it is quite useful if you are implementing an optimisation. 45. http://article.gmane.org/gmane.comp.lang.haskell.cafe/18315 Simple proof-carrying code in Haskell 98. Oleg Kiselyov [46]demonstrated a datatype `Terminates' that can hold only an assuredly terminating (strongly normalizable) term in untyped lambda-calculus. Furthermore, the values of the datatype `Terminates' contain all and only those untyped lambda-calculus terms with that property. To create the value `Terminates', the user submits the term in question and the proof of its termination. The proof will be verified -- and if it holds, the Terminates certificate will be created. 46. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/18375 Article review: Category Theory. David House [47]mentioned that he's written a chapter for the Wikibook that attempts to teach some basic Category Theory in a Haskell hacker-friendly fashion. 47. http://en.wikibooks.org/wiki/Haskell/Category_theory IO is not a monad. Yitzchak Gale [48]sparked a long thread on issues of parametricity and polymorphic seq in the IO monad 48. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/18569 Monad laws for fail. Ulf Norrel [49]wondered about what properties 'fail' should satisify 49. http://article.gmane.org/gmane.comp.lang.haskell.libraries/6162 Jobs Postdoctoral Research Fellow at St Andrews. Kevin Hammond [50]announced a vacancy for a postdoctoral research fellow, working with the Hume language developed jointly with [51]Heriot-Watt University. Knowledge of Haskell and other functional programming technologies is a distinct advantage. 50. http://article.gmane.org/gmane.comp.lang.haskell.general/14744 51. http://www.hume-lang.org/ Blog noise [52]Haskell news from the blogosphere. * [53]Haskell: Too Hard, or Just Hard Enough? * [54]One Month with Haskell * [55]foldr and foldl in JavaScript * [56]Haskell Revisited * [57]Haskell, first impressions (with sexy results) * [58]Haskell: bootstrapping into a clue about monads * [59]How To Use Monad Transformers * [60]Error handling in Haskell * [61]Learning Haskell inch by inch * [62]Haskell: the Basics of Type Classes * [63]Clockwork languages * [64]Fun with Haskell * [65]Programming Productivity and Programming Languages * [66]Second order folds * [67]Happy Haskell hacking * [68]Simple STM TCP server * [69]Languages and paradigms and cores, oh my! * [70]Bug Reporting * [71]High performance Haskell * [72]Threads * [73]Literate Haskell * [74]The end of free lunch CPU performance and other papers * [75]The monad behind every zipper * [76]The functional C programmer * [77]Strictly for Lazy Programmers * [78]Haskell introduction for beginners * [79]Haskell Basics * [80]Haskell laziness * [81]A First Step Into Monads * [82]More Monads: Stateful Programming * [83]Why the IO monad? * [84]Haskell epiphanette * [85]More About Language Productivty: Corbato's Law * [86]Laziness and fizzbuzz in Haskell * [87]C# looks scary * [88]Random thoughts 52. http://planet.haskell.org/ 53. http://neilbartlett.name/blog/?p=11 54. http://blogs.nubgames.com/code/?p=17 55. http://satta.org/2007/01/08/foldr-and-foldl-in-javascript/ 56. http://corfield.org/blog/index.cfm/do/blog.entry/entry/Haskell_Revisited 57. http://www.stonecode.org/blog/?p=101 58. http://www.serpentine.com/blog/2007/01/09/haskell-bootstrapping-into-a-clue… 59. http://cale.yi.org/index.php/How_To_Use_Monad_Transformers 60. http://edwinb.wordpress.com/2007/01/15/error-handling-in-haskell/ 61. http://e-scribe.com/news/328 62. http://scienceblogs.com/goodmath/2007/01/haskell_the_basics_of_type_cla_1.p… 63. http://journal.dedasys.com/articles/2007/01/17/clockwork-languages 64. http://braindump.dk/tech/2007/01/19/fun-with-haskell/ 65. http://josefsblog.blogspot.com/2007/01/programming-productivity-and.html 66. http://www.acooke.org/andrew/writing/folds.html 67. http://daniel-yokomizo.livejournal.com/6949.html 68. http://sequence.complete.org/node/258 69. http://nointernalmonologue.blogspot.com/2007/01/languages-and-paradigms-and… 70. http://japple.blogspot.com/2007/01/bug-reporting.html 71. http://www.randomhacks.net/articles/2007/01/22/high-performance-haskell 72. http://radar.oreilly.com/archives/2007/01/threads_conside.html 73. http://emresahin.net/2007/01/21/literate-programming-in-haskell/ 74. http://www.cpu.uttaruk.com/2007/01/25/the-end-of-free-lunch-cpu-performance… 75. http://sigfpe.blogspot.com/2007/01/monads-hidden-behind-every-zipper.html 76. http://jaortega.wordpress.com/2007/01/29/the-functional-c-programmer/ 77. http://floatingpoint.tinou.com/2007/01/strictly_for_la.html 78. http://blog.interlinked.org/tutorials/haskell_introduction.html 79. http://blog.interlinked.org/tutorials/haskell_2.html 80. http://blog.interlinked.org/tutorials/haskell_laziness.html 81. http://scienceblogs.com/goodmath/2007/01/haskell_a_first_step_into_mona_1.p… 82. http://scienceblogs.com/goodmath/2007/01/more_monads_stateful_programmi_1.p… 83. http://kawagner.blogspot.com/2007/01/real-functional-programming-or-why-io.… 84. http://rubynations.blogspot.com/2007/01/haskell-epiphanette.html 85. http://www.neilmix.com/2007/01/25/more-about-language-productivty-corbatos-… 86. http://mult.ifario.us/articles/2007/01/25/laziness-and-fizzbuzz-in-haskell 87. http://garybernhardt.blogspot.com/2007/01/c-30-looks-promising.html 88. http://poundbang.in/2007/01/22/post-barcamp-thoughts-comments/ Quotes of the Week * ndm: [dons] How do we serialise an Int portably? [ndm] Just use the first 29 bits * C.M.Brown: I told them they could all finish the class in 5 minutes if they used Haskell... The look of horror on the student's faces when I mentioned the 'H' word was priceless. However, they were all prepared to spend 50 minutes writing a Java program which would have the same effect. * dons: dons law: if you have a bug, you are missing a QC property * BjarneStroustrup: Within C++, there is a much smaller and cleaner language struggling to get out. * ClaudiusMaximus: Compiling with -O2 reduced the time taken by my program's execution from 28 mins to 17 seconds. * dons: Think of a monad as a spacesuite full of nuclear waste in the ocean next to a container of apples. now, you can't put oranges in the space suite or the nucelar waste falls in the ocean, *but* the apples are carried around anyway, and you just take what you need. * Runar Jordahl: Haskell has quite the following among the alpha geeks * bakert: I know all my programs can be reduced to only one tenth the size if only I can learn all these crazy functions * glguy: [on hpaste.org] you can have your code syntax colored however you like, as long as that color is 'haskell' * huschi: Programing in haskell seems a bit frustrating. i'm missing searching for errors :( * dons: I had a dream about how to write instance Binary Integer last night * bd: If a graph is reduced in a forest, and no one is around to pattern match the resulting WHNF, does it cause a space leak? * bos: [dons] and stricify, specialise and inline as appropriate till the raw bytestring Addr# start appearing [bos] um, is that next to the dilithium crystals? * kolmodin: It's nice to have static types after a bottle of wine * nmessenger: Brain explosion is like a traditional pasttime in #haskell Code Watch Thu Jan 11 05:13:59 PST 2007. Pepe Iborra. [89]Added the new :breakpoint continue option. Previously, when in a breakpoint, :quit was used to continue execution. This is not the right thing to do, so this patch restores :quit to its original meaning whether or not ghci is in an inferior session. The continue behavior is now provided by ':breakpoint continue'. I added a synonim command in :continue because it is much shorter, but this is optional About the Haskell Weekly News Each week, new editions are posted to [90]the Haskell mailing list as well as to [91]the Haskell Sequence and [92]Planet Haskell. [93]RSS is also available, and headlines appear on [94]haskell.org. Headlines are available as [95]PDF. To help create new editions of this newsletter, please see the [96]contributing information. Send stories to dons at cse.unsw.edu.au. The darcs repository is available at darcs get [97]http://www.cse.unsw.edu.au/~dons/code/hwn 89. http://article.gmane.org/gmane.comp.lang.haskell.cvs.ghc/18817 90. http://www.haskell.org/mailman/listinfo/haskell 91. http://sequence.complete.org/ 92. http://planet.haskell.org/ 93. http://sequence.complete.org/node/feed 94. http://haskell.org/ 95. http://www.cse.unsw.edu.au/~dons/code/hwn/archives/20070131.pdf 96. http://haskell.org/haskellwiki/HWN 97. http://www.cse.unsw.edu.au/~dons/code/hwn

1 0

Software is at Dead End?
by Tracy R Reed 30 Jan '07

30 Jan '07

Hello folks! This article on /. (boo, hiss, I know, but it is read by many) presents a problem looking for a solution. And Haskell may well be the solution. http://it.slashdot.org/article.pl?sid=07/01/30/1547235 I have already chimed in on the thread and I thought a few of you might also. Seems like the perfect opportunity for some friendly haskell advocacy since the people who read this article are more likely to be concerned about the future of software development and looking for a solution like Haskell. -- Tracy R Reed http://ultraviolet.org A: Because we read from top to bottom, left to right Q: Why should I start my reply below the quoted text

3 2