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ANN: pandoc 1.0.0.1
by John MacFarlane 18 Sep '08

18 Sep '08

I'm pleased to announce the release of pandoc version 1.0.0.1. Pandoc aspires to be the swiss army knife of text markup formats: it can read markdown and (with some limitations) HTML, LaTeX, and reStructuredText, and it can write markdown, reStructuredText, HTML, DocBook XML, OpenDocument XML, ODT, RTF, groff man, MediaWiki markup, GNU Texinfo, LaTeX, ConTeXt, and S5. Pandoc's markdown syntax includes extensions for LaTeX math, tables, definition lists, footnotes, and more. HackageDB: http://hackage.haskell.org/cgi-bin/hackage-scripts/package/pandoc User's guide: http://johnmacfarlane.net/pandoc/README.html Examples: http://johnmacfarlane.net/pandoc/examples.html Interactive demo: http://johnmacfarlane.net/pandoc/trypandoc/ Haddock docs: http://johnmacfarlane.net/pandoc/doc/pandoc/ Repository: http://pandoc.googlecode.com/ Bug tracker: http://code.google.com/p/pandoc/issues/list Mailing list: http://groups.google.com/group/pandoc-discuss Some highlights of this release: + New GNU Texinfo writer (contributed by Peter Wang) + New OpenDocument XML writer (contributed by Andrea Rossato) + New ODT (OpenOffice document) writer + New MediaWiki markup writer + New delimited code block syntax + Handy generic functions for querying and transforming documents without lots of boilerplate (thanks to Andrea Rossato) + Cleaner build system: pandoc can now be built as a regular Cabal package + New dependencies: utf8-string and zip-archive + Code is -Wall clean + New Windows installer + Better support for math, including display math + Better HTML sanitizing for use in web applications + Many minor improvements and bug fixes (see changelog for details) Pandoc can optionally be compiled with support for + syntax highlighting of delimited code blocks, using the highlighting-kate library (over 50 languages are supported) (specify -fhighlighting) + automatically generated citations and bibliography, using Andrea Rossato's hs-citeproc library (specify -fciteproc) I am particularly excited about Rossato's experimental citation support. It's basically a BibTeX-like system that one can use in any of pandoc's output formats. So you can have automatically generated citations in a blog post, a wiki page, or even a man page! It's not yet complete, but it's far enough along for those with an adventurous spirit to use. I am very grateful to everyone who contributed bug reports and code, and especially to Andrea Rossato and Peter Wang for their major contributions.

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announcing darcs 2.0.3pre1
by Eric Kow 18 Sep '08

18 Sep '08

Hi everybody, I am very pleased to announce the first pre-release of darcs 2.0.3, available at http://www.darcs.net/darcs-2.0.3pre1.tar.gz This pre-release includes a few major bug fixes and a handful of interesting features. I expect darcs 2.0.3 to be more reliable than its predecessors. We have better HTTP support, safer handling of the pending patch and a more solid implementation of common flags (for example, darcs get --to-match or darcs diff --patch). For more details, see the attached list. So what are we working on to get darcs 2.0.3 out the door? Aside from the usual testing, I hope that we can round out our improved reliability with a few small user interface enhancements, mostly to help users avoid some common pitfalls of real world version control: - issue53: detection of Windows reserved device names - issue971: hashed darcs check - issue1003: more tolerant darcs-transfer mode - issue1039: detection of seemingly unrelated repositories (see http://bugs.darcs.net for details) In the meantime, please give darcs 2.0.3pre1 a try and let us know how things go! Thanks, -- Eric Kow <http://www.nltg.brighton.ac.uk/home/Eric.Kow> PGP Key ID: 08AC04F9

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Ajax-Haskell framework?
by Greg Meredith 18 Sep '08

18 Sep '08

Haskellians, Is there an Ajax-Haskell framework? In case there are many, is there a preferred one? Experiences people would like to share? Best wishes, --greg -- L.G. Meredith Managing Partner Biosimilarity LLC 806 55th St NE Seattle, WA 98105 +1 206.650.3740 http://biosimilarity.blogspot.com

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Haskell Weekly News: Issue 85 - September 13, 2008
by Brent Yorgey 18 Sep '08

18 Sep '08

--------------------------------------------------------------------------- Haskell Weekly News http://sequence.complete.org/hwn/20080913 Issue 85 - September 13, 2008 --------------------------------------------------------------------------- Welcome to issue 85 of HWN, a newsletter covering developments in the [1]Haskell community. Announcements citeproc-hs. Andrea Rossato [2]announced the first release of [3]citeproc-hs, a Haskell implementation of the [4]Citation Style Language. citeproc-hs adds a Bibtex-like citation and bibliographic formatting and generation facility to [5]Pandoc. Twidge. John Goerzen [6]announced the release of [7]Twidge, a command-line Twitter and Identi.ca client. Real World HAppS: Cabalized, Self-Demoing HAppS Tutorial (Version 3). Thomas Hartman [8]announced a new version of [9]happs-tutorial, with a correspondingly updated [10]online demo. generic list functions fixed. Jim Apple reported that genericTake, genericDrop, and genericSplitAt have [11]been fixed so they are now total functions (they used to fail on negative integer inputs, unlike their ungeneric counterparts). The Monad.Reader (13) - Call for copy. Wouter Swierstra [12]announced a call for copy for Issue 13 of the [13]Monad.Reader. The deadline for submitting articles is February 13, 2009. Heads Up: code.haskell.org is upgrading to darcs 2. Duncan Coutts [14]announced that /usr/bin/darcs on code.haskell.org will soon be upgraded to version 2. Most users should be unaffected as darcs 2 works just fine with repositories in darcs 1 format, and has been extensively tested for correctness. Discussion packages and QuickCheck. Conal Elliott [15]asked what methods of organization people use to package up QuickCheck tests for their libraries. Hackage needs a theme song!. Jason Dagit wrote a [16]theme song for Hackage! Jobs Gamr7. Lionel Barret De Nazaris [17]announced that [18]Gamr7, a startup in France focused on procedural city generation for the game and simulation market, is looking for a senior developer/technical director. senior role at Credit Suisse. Ganesh Sittampalam [19]announced that [20]Credit Suisse is seeking to recruit an expert in functional programming for a senior role in the Global Modelling and Analytics Group (GMAG) in the Securities Division. Blog noise [21]Haskell news from the [22]blogosphere. * Douglas M. Auclair (geophf): [23]What is declarative programming?. * John Goerzen (CosmicRay): [24]New Twitter Client: Twidge. * Mark Jason Dominus: [25]Return return. Mark's mind is blown by the code "return return" appearing in a paper by Mark Jones. * Eric Kow (kowey): [26]darcs weekly news #3. * Ketil Malde: [27]The FastQ file format for sequences. * >>> Nathan Sanders: [28]Real World Haskell. Nathan experiments with porting some of his Python code to Haskell. * Andrea Vezzosi (Saizan): [29]Results from GSoC. Andrea's GSoC work on a high-level dependency framework for Cabal is going to be released in a separate package for now, [30]hbuild. * >>> Ricky Clarkson: [31]An IRC Bot in Haskell, 20% code, 80% GRR. Ricky shares his experiences, frustrations, and eventual success writing a simple IRC bot in Haskell. * >>> Yaakov Nemoy: [32]Xmonad 0.8 released. * Luke Palmer: [33]The problem with Coq. ...is, according to Luke, that it doesn't have a nice graphical interface. * >>> James Cowie: [34]Haskell! yes no?. James dives into learning some Haskell. Verdict so far: a "very nice language". Quotes of the Week * EvilTerran: this is hard to express in this type system. i'm going to make my own type system instead! About the Haskell Weekly News New editions are posted to [35]the Haskell mailing list as well as to [36]the Haskell Sequence and [37]Planet Haskell. [38]RSS is also available, and headlines appear on [39]haskell.org. To help create new editions of this newsletter, please see the information on [40]how to contribute. Send stories to byorgey at cis dot upenn dot edu. The darcs repository is available at darcs get [41]http://code.haskell.org/~byorgey/code/hwn/ . References 1. http://haskell.org/ 2. http://article.gmane.org/gmane.comp.lang.haskell.cafe/44471 3. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/citeproc%2Dhs 4. http://xbiblio.sourceforge.net/csl/ 5. http://johnmacfarlane.net/pandoc/ 6. http://article.gmane.org/gmane.comp.lang.haskell.cafe/44453 7. http://software.complete.org/twidge 8. http://article.gmane.org/gmane.comp.lang.haskell.cafe/44410 9. http://hackage.haskell.org/cgi-bin/hackage-scripts/package/happs-tutorial 10. http://happstutorial.com:5001/ 11. http://hackage.haskell.org/trac/ghc/ticket/2533 12. http://article.gmane.org/gmane.comp.lang.haskell.general/16420 13. http://www.haskell.org/haskellwiki/The_Monad.Reader 14. http://article.gmane.org/gmane.comp.lang.haskell.general/16419 15. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/44259 16. http://thread.gmane.org/gmane.comp.lang.haskell.cafe/44450 17. http://article.gmane.org/gmane.comp.lang.haskell.cafe/44211 18. http://www.gamr7.com/ 19. http://article.gmane.org/gmane.comp.lang.haskell.general/16422 20. http://www.credit-suisse.com/ 21. http://planet.haskell.org/ 22. http://haskell.org/haskellwiki/Blog_articles 23. http://logicaltypes.blogspot.com/2008/09/what-is-declarative-programming.ht… 24. http://changelog.complete.org/posts/752-New-Twitter-Client-Twidge.html 25. http://blog.plover.com/prog/springschool95.html 26. http://koweycode.blogspot.com/2008/09/darcs-weekly-news-3.html 27. http://blog.malde.org/index.php/2008/09/09/the-fastq-file-format-for-sequen… 28. http://sandersn.com/blog/index.php?title=real_world_haskell 29. http://vezzosi.blogspot.com/2008/09/even-if-this-blog-has-been-silent-since… 30. http://hackage.haskell.org/trac/hackage/wiki/HBuild 31. http://rickyclarkson.blogspot.com/2008/09/irc-bot-in-haskell-20-code-80-grr… 32. http://loupgaroublond.blogspot.com/2008/09/xmonad-08-released.html 33. http://luqui.org/blog/archives/2008/09/07/the-problem-with-coq/ 34. http://www.jcowie.co.uk/2008/09/haskell-yes-no/ 35. http://www.haskell.org/mailman/listinfo/haskell 36. http://sequence.complete.org/ 37. http://planet.haskell.org/ 38. http://sequence.complete.org/node/feed 39. http://haskell.org/ 40. http://haskell.org/haskellwiki/HWN 41. http://code.haskell.org/~byorgey/code/hwn/

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a question about Database.HDBC.ODBC
by Changying Li 18 Sep '08

18 Sep '08

I want to use hdbc to connect my mysql test db. so I set up my /etc/odbcinst.ini : [MySQL] Description = ODBC Driver for MySQL Driver = /usr/lib/libmyodbc.so Setup = /usr/lib/libodbcmyS.so FileUsage = 1 and /etc/odbc.ini: [test] Description = MySQL database test Driver = MySQL Server = localhost Database = test Port = 3306 User = root Socket = /tmp/mysql.sock Option = Stmt = user chylli@localhost must use password to connect mysql. other users needn't. I connect db like this: Prelude Database.HDBC.ODBC Database.HDBC> handleSqlError (connectODBC "DSN=test") *** Exception: user error (SQL error: SqlError {seState = "[\"HY000\"]", seNativeError = -1, seErrorMsg = "connectODBC/sqlDriverConnect: [\"1045: [unixODBC][MySQL][ODBC 3.51 Driver]Access denied for user 'chylli'@'localhost' (using password: NO)\"]"}) Prelude Database.HDBC.ODBC Database.HDBC> handleSqlError (connectODBC "DSN=test;UID=chylli") Prelude Database.HDBC.ODBC Database.HDBC> in another term: mysql> show processlist; +----+-------------+-----------+------+---------+------+-------+------------------+ | Id | User | Host | db | Command | Time | State | Info | +----+-------------+-----------+------+---------+------+-------+------------------+ | 31 | chylli¶è | localhost | test | Sleep | 1483 | | NULL | | 43 | root | localhost | test | Sleep | 116 | | NULL | my question is: 1. why not HDBC.ODBC use configuration in /etc/odbc.ini ? if is use, then connectODBC "DSN=test" should use root as user without password and it should succeed. 2. when using UID=chylli, why the user in 'show processlist' is not chylli but 'chylli¶è' ? if it use account 'chylli', that connection should fail. but in fact it succeed !!! -- Thanks & Regards Changying Li

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Re: [Haskell-cafe] Re: Python's big challenges, Haskell's big advantages?
by Richard A. O'Keefe 18 Sep '08

18 Sep '08

It may be of interest that although Erlang has been doing lightweight concurrency for >20 years, - you can choose whether you want to use an SMP version that has as many schedulers as there are cores (plus internal locking as needed) or a non-SMP version with one scheduler (and no internal locking); both versions are standard and it's only a performance issue, not a semantics issue - performance sometimes goes one way, sometimes the other - there was a "one UNIX process per Erlang process" implementation; I have a copy. The community interest in it was, shall we say, massively underwhelming. It might also be interesting to note that the experimental operating system K42 from IBM does _all_ user-visible threading in user-land. This includes thread switching and even I/O blocking and unblocking; all done in user-land. I don't think we've begun to explore all the options yet.

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about openTempFile
by Manlio Perillo 17 Sep '08

17 Sep '08

Hi. After reading the chapter about IO in the "Real Word Haskell" book, I have noted that there is no support for opening a temporary file that will be automatically removed at program termination. The Python tempfile module, as an example, implements a wrapper around mkstemp function that does exactly this, and the code is portable; on Windows it uses O_TEMPORARY_FILE flag, on POSIX systems the file is unlink-ed as soon as it is created (but note that the code is not signal safe - well, many functions in the Python standard library are not signal safe). There are reasons why GHC library does not implement this? The Python version also set the FD_CLOEXEC, O_NOINHERIT and O_NOFOLLOW flags (where available). The GHC version, instead, set the O_NOCTTY flag. Manlio Perillo

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Re: [Haskell-cafe] Re: Python's big challenges, Haskell's big advantages?
by Donn Cave 17 Sep '08

17 Sep '08

Quoth Jonathan Cast <jonathanccast(a)fastmail.fm>: ... | Say what? This discussion is entirely about performance --- does | CPython actually have the ability to scale concurrent programs to | multiple processors? Well, ostensibly the discussion also has something to do with Haskell. On that premise, may I say I hope we're not inspired by Python's example to treat concurrency as a religious matter. The C Python community is forced to take the position that interpreter- level threading is not worth the price, because they don't have it and can't conveniently get it. I doubt we'll ever know for sure whether they're right or wrong, since Python comes with other issues that could also take blame or credit for its success at large scale applications. The Haskell community seems to be convinced as a whole that user-level threads are the way to go, but at most that's just a majority, not a consensus. Who cares!? Given the ability to take either path, Haskell programmers will solve our religious argument - we'll know who gets to heaven with working, high performance, reliable applications. That is, assuming that programmers of each persuasion can find Haskell suited to their model. As far as I know, though, that isn't a really sure thing. I've read things like "thread RTS can't/shouldn't support fork" and "would like to be able to get rid of the non-threaded RTS", with respect to GHC. At least until there is more empirical evidence that it's a waste of time, Haskell implementations should leave this to the programmer - support processes, OS threads, or user threads without undue work-around burdens. Otherwise we'll be stuck like the Python community is, defending this approach as a religious argument. We have enough of those already. Donn Cave, donn(a)avvanta.com

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How to check if two Haskell files are the same?
by Mauricio 17 Sep '08

17 Sep '08

Hi, I would like to write a Haskell pretty-printer, using standard libraries for that. How can I check if the original and the pretty-printed versions are the same? For instance, is there a file generated by GHC at the compilation pipe that is always guaranteed to have the same MD5 hash when it comes from equivalent source? Thanks, Maurício

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Float instance of 'read'
by Mauricio 17 Sep '08

17 Sep '08

Hi, A small annoyance some users outside english speaking countries usually experiment when learning programming languages is that real numbers use a '.' instead of ','. Of course, that is not such a problem except for the inconsistence between computer and free hand notation. Do you think 'read' (actually, 'readsPrec'?) could be made to also read the international convention (ie., read "1,5" would also work besides read "1.5")? I'm happy to finaly use a language where I can use words of my language to name variables, so I wonder if we could also make that step. Thanks, Maurício

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