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Haskell email
by Simon Peyton-Jones 05 Jan '06

05 Jan '06

John, Haskellers Thanks to Thomas Johnsson and Libor, I've put together a complete archive of the Haskell mailing list, from 11 Sept 1990 (birth, I think) to Oct 2000 (when the Haskell.org mailman archive takes over). It's available here http://research.microsoft.com/%7Esimonpj/haskell/haskell-email-11Sep1990 -27Oct2000.gz (or will be shortly). John: worth pointing to from Haskell.org? Others: it's a single giant text file. It'd be good to import it into mailman, so that there's exactly one place to look, if someone knows how to do that. Simon

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RE: [Haskell] A collection of related proposals regarding monads
by Simon Peyton-Jones 05 Jan '06

05 Jan '06

Simon Marlow pointed me to mail-archive.com. For some reason Google doesn't seem to index this site, and it's not an easy site to navigate around. However, you can find the monadzero thread mostly on this page: http://www.mail-archive.com/haskell@haskell.org/thrd16.html (search for MonadZero) Simon | -----Original Message----- | From: haskell-bounces(a)haskell.org | [mailto:haskell-bounces@haskell.org] On Behalf Of Simon Peyton-Jones | Sent: 05 January 2006 09:06 | To: Cale Gibbard; Haskell Mailing List | Subject: RE: [Haskell] A collection of related proposals | regarding monads | | | | What do people think of the following proposal? Remove fail from the | | Monad class. Reinstate MonadZero as a separate class as in Haskell | | 1.4. | | This was debated extensively during the Haskell 98 process. I'm not | saying that we made the right decision then, but here's a link to (a | part of) the discussion. | | http://www.cs.chalmers.se/~rjmh/Haskell/Messages/Decision.cgi?id=2 | | I'm hoping someone has an archive of the whole mailing list they can | let us have (see my other message) | | Simon | _______________________________________________ | Haskell mailing list | Haskell(a)haskell.org | http://www.haskell.org/mailman/listinfo/haskell |

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RE: [Haskell] A collection of related proposals regarding monads
by Simon Peyton-Jones 05 Jan '06

05 Jan '06

| What do people think of the following proposal? Remove fail from the | Monad class. Reinstate MonadZero as a separate class as in Haskell | 1.4. This was debated extensively during the Haskell 98 process. I'm not saying that we made the right decision then, but here's a link to (a part of) the discussion. http://www.cs.chalmers.se/~rjmh/Haskell/Messages/Decision.cgi?id=2 I'm hoping someone has an archive of the whole mailing list they can let us have (see my other message) Simon

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Haskell mailing list archive
by Simon Peyton-Jones 05 Jan '06

05 Jan '06

Dear Haskellers Does anyone have a complete archive of Haskell mailing list messages between May 1998 and October 2000 On the latter date we moved to mailman, hosted at haskell.org, so there are archives at haskell.org. I have a complete archive up to May 1998, courtesy of Thomas Johnsson. (I guess I should put it on haskell.org somewhere.) But there's a gap where there seems to be nothing. One reason for asking is that in 1998 there was a long debate about Monad/MonadZero, which is a current topic on the the Haskell list. We'd be better informed if we had the old threads to look at. Simon

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Using MonadError within other Monads
by tpledger＠ihug.co.nz 04 Jan '06

04 Jan '06

(In reply to http://www.haskell.org/pipermail/haskell/2005-December/017109.html ) One of the key things about those nested monads is that *often* you don't have to write things like return $ throwError msg but can simply write throwError msg because the nest has all the features of its components. The IO monad doesn't participate fully in this, but the liftIO function (from the MonadIO class) serves as an adapter. > import Control.Monad.Error > f () = do n <- liftIO readLn > when (n == 2) (throwError "2-char string") > sequence (replicate n (liftIO getChar)) > `catchError` (throwError . ("g Error: "++)) (Pay no attention to the () parameter behind the curtain! I'm dodging the monomorphism restriction, and don't want to give an explicit type signature.) The inferred type is f :: (MonadError [Char] m, MonadIO m) => () -> m [Char] i.e. it's usable for any nest of monads that provides the MonadError String and MonadIO features. Now, how to run it? Your type signatures of the form IO (Either String String) are very reminiscent of the ErrorT monad transformer newtype ErrorT e m a = ErrorT {runErrorT :: (m (Either e a))} with IO as m and String as e and a. So, let's test f in ErrorT String IO. *Main> runErrorT (f ()) >>= print 0 Right "" *Main> runErrorT (f ()) >>= print 2 Left "I don't like strings with 2 characters." *Main> runErrorT (f ()) >>= print 4 Too Right "Too\n" Regards, Tom

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Open source project idea
by Craig Ugoretz 03 Jan '06

03 Jan '06

Hello, My name is Craig Ugoretz. For the past eight months, I have been researching an approach to programming a mathematical software application. This application will be based upon a collection of books written by Dr. Florentin Smarandache on the subjects of neutrosphic logic and neutrosophic cognitive maps. The applications of these new mathematical ideas are to better model paradoxes and contradictions in reasoning and the combined opinions of experts regarding sociopolitical situations. The books of interest to me form a subset of the material found on the website http://www.gallup.unm.edu/~smarandache/eBooks-otherformats.htm. The reason that I have written this mailing list is that I am looking for knowledgable Haskell programmers to aid me in writing this software. I have yet to learn Haskell, although I did have some success learning its "functional cousin", OCAML. I picked Haskell for this project because functional programming languages model mathematics more easily, and because I may have a need for computer algebra functionality in the application - so the DoCon Haskell library may be needed, if I understand its purpose correctly. Additionally, if there are people experienced with architecting Haskell programs or managing a Haskell programming project, their help may be invaluable as I finalize the research approach. The final software will be open source, meaning that the binaries and source code will be freely available to the public. If you are interested in participating in this effort, please let me know. I personally find functional programming and the mathematics of neutrosophy to be most interesting, and I derive value from the fact that this software could be used for a purpose that would benefit society. I look forward to your response. If you have concerns about what I have written above, also please let me know. Sincerely, Craig Ugoretz craigugoretz(a)yahoo.com

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Haskell Weekly News: January 3, 2005
by dons＠cse.unsw.edu.au 02 Jan '06

02 Jan '06

Haskell Weekly News: January 3, 2005 Greetings, and thanks for reading the 18th issue of HWN, a weekly newsletter for the Haskell community. Each Monday, new editions will be posted (as text) to [1]the Haskell mailing list and (as HTML) to [2]The Haskell Sequence. This issue brings a change to the Haskell Weekly News as Don Stewart takes over from John Goerzen as editor. Thanks goes to John for his excellent work on the first 17 editions! 1. http://www.haskell.org/mailman/listinfo/haskell 2. http://sequence.complete.org/ New Releases * Process library. Bulat Ziganshin announced a [3]new library abstracting over some of the process and concurrency functions in the standard libraries, using ideas from Unix pipes. 3. http://article.gmane.org/gmane.comp.lang.haskell.general/12728 * Djinn. Lennart Augustsson [4]released Djinn, a theorem prover/coding wizard, that generates Haskell code from a given type. A lambdabot plugin for Djinn was also written, for use in #haskell. 4. http://article.gmane.org/gmane.comp.lang.haskell.general/12747 * Ranged Sets. Paul Johnson released a [5]ranged sets library 0.0.1 and [6]0.0.2. Ranged sets allow programming with sets of values that are described by a list of ranges. A value is a member of the set if it lies within one of the ranges. 5. http://article.gmane.org/gmane.comp.lang.haskell.general/12749 6. http://article.gmane.org/gmane.comp.lang.haskell.general/12827 * Hmp3. Don Stewart [7]announced a stable release of hmp3, an curses-based mp3 player written in Haskell. Portability has improved, and binaries are available for 5 architectures. 7. http://article.gmane.org/gmane.comp.lang.haskell.general/12787 * HSQL. Krasimir Angelov released [8]HSQL 1.7. New features include a driver for Oracle. 8. http://article.gmane.org/gmane.comp.lang.haskell.general/12798 * HDBC. John Goerzen announced the [9]0.5.0, [10]0.6.0 and [11]0.99.0 releases of Haskell Database Connectivity library. Patterned after Perl's DBI, it includes an Sqlite3 and a [12]PostgreSQL backend 9. http://article.gmane.org/gmane.comp.lang.haskell.general/12820 10. http://article.gmane.org/gmane.comp.lang.haskell.general/12833 11. http://article.gmane.org/gmane.comp.lang.haskell.general/1286 12. http://article.gmane.org/gmane.comp.lang.haskell.general/12843 * Shellac. Robert Dockins [13]released Shellac, a framework for building read-eval-print style shells. This should ease the burden of binding readline-style interactive shells in Haskell. 13. http://article.gmane.org/gmane.comp.lang.haskell.general/12823 * Lambda Shell. Robert Dockins also released v0.1 of [14]Lambda Shell, a shell environment for evaluating terms of the pure, untyped lambda calculus. A lambdabot interface for use in #haskell also exists. 14. http://article.gmane.org/gmane.comp.lang.haskell.general/12824 * Shaskell. David Mercer [15]announced version 0.21a of Shaskell, a SHA2 library for sha256 and sha512 hashes, written in pure Haskell. 15. http://article.gmane.org/gmane.comp.lang.haskell.general/12863 * hdbc-missingh. John Goerzen [16]announced the initial release of HDBC-MissingH, a library to add database features to MissingH, allowing the use of a SQL database as storage for a simple DBM-like key/value interface. 16. http://article.gmane.org/gmane.comp.lang.haskell.general/12896 Discussion * Making Haskell More Open. Simon Peyton-Jones reinitiated a [17]discussion on how to make Haskell more open, and in particular how to make it easier for Haskell users to contribute. 17. http://thread.gmane.org/gmane.comp.lang.haskell.general/12804 * The Unboxed Kind. Ashley Yakeley [18]asked about creating type variables with unboxed kind. This lead to an interesting discussion about the difficulties that result, including the problems of polymorphic functions over unboxed values. 18. http://thread.gmane.org/gmane.comp.lang.haskell.general/12849 Haskell Toolchain Fptools in Darcs. John Goerzen has [19]set up live darcs mirrors of fptools, ready for testing. With over 13,000 patches in fptools, you'll want to use --partial. 19. http://article.gmane.org/gmane.comp.lang.haskell.general/12694 Darcs Corner * Darcs 1.0.5. A stable release of [20]Darcs 1.0.5 was made. This release includes fixes for Windows, as well as some new features. 20. http://article.gmane.org/gmane.comp.version-control.darcs.user/9009 * darcsweb. Alberto Bertogli [21]announced darcsweb 0.13, a rather lovely web interface to darcs repositories. 21. http://article.gmane.org/gmane.comp.version-control.darcs.user/9072 Quotes of the Week <sieni> State? <sieni> There is no state :-) <shapr> Haskell separates Church and state. About Haskell Weekly News Want to continue reading HWN? You can help us create new editions of this newsletter. Please see the [22]contributing information, send stories to dons -at- cse.unsw.edu.au. The Darcs repository is available at darcs get http://www.cse.unsw.edu.au/~dons/code/hwn 22. http://sequence.complete.org/hwn-contrib

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HWN Editor Found
by John Goerzen 02 Jan '06

02 Jan '06

I'm pleased to announce that Donald Stewart has agreed to take over as editor of HWN and will be publishing his first issue shortly. Thank you very much, Donald! -- John

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Re: Haskell Digest, Vol 28, Issue 22
by Paul Johnson 31 Dec '05

31 Dec '05

Cale Gibbard wrote: >If something looks like 'article' material, you should feel free to >edit however you like, but usually you should try not to outright >remove valid content. In any event, all the old versions are kept, so >it's no big deal if something goes missing for a while. > Could I also point out the slowly developing WikiBook on Haskell at http://en.wikibooks.org/wiki/Programming:Haskell If what you are writing has a tutorial flavour then see if it would fit there. Paul.

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modern Arrays documented?
by Bulat Ziganshin 31 Dec '05

31 Dec '05

Hello haskell, i'm ready to write my own guide to using modern Arrays library (i mean MArray/IArray machinery, unboxed arrays, diff. arrays and parallel arrays). but may be there is already some docs on this topic (i don't count contents of modules itself)? -- Best regards, Bulat mailto:bulatz@HotPOP.com

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