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Anglo Haskell 2008
by Matthew Sackman 11 Aug '08

11 Aug '08

Anglo Haskell is a gathering of all people Haskell-related from beginners, to seasoned hackers to academic giants. All and more are welcomed by large fuzzy green lambdas. Anglo Haskell has happened for the last two years and we see no reason why it should not happen again this year. For the last two years they've tended to have talks on Fridays and then Other Things on the Saturday (including Punting and Group Hacking, some or more of which may have happened in Pubs). We're proposing the same general format this year. In contrast to the last two years which have been held at MSR Cambridge (UK), we're this year proposing to hold the event at Imperial College, London. London is probably easier to get to and from (though more tedious to get across) than Cambridge and we hope this will attract people who previously have not been able to get out to Cambridge. The proposed dates are Friday the 8th and Saturday the 9th of August. More details are available on the wikipage: http://www.haskell.org/haskellwiki/AngloHaskell/2008 Please feel free to add to this page. If you're at all interested in coming along then please add your name to the wikipage. If you're interested in giving a talk - on literally anything Haskell related: this is not a solely theory day or solely a practical day; anything goes which is Haskell related - then similarly add yourself to the list of speakers. Schedule and other details will be confirmed soon. Lodging, travel and all other related matters will be discussed on the irc channel (and will eventually migrate to the wikipage) #anglohaskell. If you're free that weekend then please come along! Also, if you'd really like to come but can't make those dates and there are many of you then please shout loudly and things could potentially be moved, though with the lack of time left before the event, we'd prefer to avoid this. Matthew

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Lambdabot
by Thomas Davie 11 Aug '08

11 Aug '08

I've been trying to lambdabot running properly recently, and have consistently hit an error "fd:6: hClose: resource vanished (Broken pipe)" whenever I try to run anything that involves executing haskell (including but not limited to evaluating arbitrary expressions, the brainfuck module, unlambda). A quick google revealed that it's a very common error, but not potential solutions. Any ideas on what's up would be very useful. Bob

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I want to upgrade to ghc 6.8.3
by Galchin, Vasili 11 Aug '08

11 Aug '08

Hello, I am building 6.8.3 from my "local" 6.8.2. However, I am getting errors in compiling one of the Main.hs. E.g. Main.hs:76:23: Ambiguous occurrence `flags' It could refer to either `Main.flags', defined at Main.hs:118:0 or `System.Posix.flags', imported from System.Posix at Main.hs:59:0-18 ...... I did a "find . -name Main.hs" and there are several Main.hs. I am not sure which one is causing trouble or why. ?? Kind regards, Vasili

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help
by shoulders 11 Aug '08

11 Aug '08

--------------------------------- 雅虎邮箱，您的终生邮箱！

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please help me to find errors from my first app
by Changying Li 11 Aug '08

11 Aug '08

Hi. I want to write a reverse proxy like perlbal to practive haskell. Now I just write a very simple script to forward any request to www.google.com. but it dosn't work. I run command ' runhaskell Proxy.hs' and 'wget http://localhost:8080/'. but wget just wait forever and runhaskkell can get request. when I break wget, the 'runhaskell' can print response returned from www.google.com. why? module Main where import System.Posix.Process import Network import Prelude hiding (putStr) import System.IO hiding (hGetContents, putStr) import Control.Concurrent import System.Posix.Signals import Data.ByteString.Lazy.Char8 (hGetContents, hPut, putStr,hGet,cons) listenPort = PortNumber 8080 connectToHost = "208.67.219.230" connectToPort = PortNumber 80 main :: IO () main = do hSetBuffering stdout NoBuffering socket <- listenOn listenPort let doLoop = do (hdl, _, _) <- accept socket forkIO $ processRequest hdl doLoop doLoop processRequest :: Handle -> IO () processRequest hRequest = do installHandler sigPIPE Ignore Nothing; hSetBuffering hRequest NoBuffering hSetBuffering stdout NoBuffering request <- hGetContents hRequest putStr $ '>' `cons` (' ' `cons` request) hResponse <- connectTo connectToHost connectToPort hSetBuffering hResponse NoBuffering hPut hResponse request response <- hGetContents hResponse putStr $ '<' `cons` (' ' `cons` response) hPut hRequest response hClose hRequest hClose hResponse -- Thanks & Regards Changying Li

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heap lifetime question
by Galchin, Vasili 10 Aug '08

10 Aug '08

Hello, What is the lifetime of various heap objects ... e.g. created by allocaBytes, alloca, etc? Regards, Vasili

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Re: ANN: interval and polynomial enclosure arithmetics
by Michal Konecny 10 Aug '08

10 Aug '08

Roman Cheplyaka <roma <at> ro-che.info> writes: > * Michal Konecny <mik <at> konecny.aow.cz> [2008-08-08 13:38:56+0100] > > and members of the KEG research group at Aston > > University have used it for reliably solving differential equations > > and numerical constraint satisfaction problems. > > This's very interesting. Do you have any published papers (or other > sources of information) about it? Unfortunately, there isn't much yet but more is on the way. Only the following two papers are available at the moment: http://www-users.aston.ac.uk/~konecnym/papers/cfv08.html is about using our polynomial enclosures to prove NCSPs that arise from floating-point software verification problems. http://www-users.aston.ac.uk/~konecnym/papers/wollic08.html analyses the convergence rate of an ODE solver that uses piecewise constant enclosures (which is rather inefficient). Best regards, Michal -- |o| Michal Konecny |o| http://www-users.aston.ac.uk/~konecnym/ |o| office: (+42) (0)121 204 3462 |o| PGP key http://www-users.aston.ac.uk/~konecnym/ki.aow

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Last Reminder: The Italian Haskellers Summer Meeting takes place tomorrow at Monterosso, 5 Terre
by Titto Assini 10 Aug '08

10 Aug '08

Il titolo dice tutto, maggiori dettagli ad: http://www.haskell.org/haskellwiki/?title=ItaloHaskell/Summer_2008 A domani, titto -- Pasqualino "Titto" Assini, Ph.D. 25 Heath Road - CO79PT Wivenhoe - Colchester - U.K.

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Future of Darcs: Thanks for the poll responses and increase in contributors
by Jason Dagit 10 Aug '08

10 Aug '08

Hello, I just wanted to thank everyone that has shown their support for darcs recently by either stopping by #darcs on freenode or joining in discussions on the darcs-user mailing list. I'm cross posting to haskell-cafe because I suspect many of you came from there. There has been a lot of enthusiasm from people, a lot of discussion about patch theory and excitement about fixing bugs and performance issues. Several people have taken an interest in making darcs work flawlessly on the GHC repository (yes, I know they have already commited to switching, but it gives a great test case to improve on). Eric Kow and myself have been working on a roadmap for future darcs improvements, and we plan to annouce an official version soon. The tentative one can be found here: http://wiki.darcs.net/DarcsWiki/Roadmap Mainly I just wanted to say, Thanks! We're considering the feedback we received from the poll and the future of darcs is not uncertain and we'll do a better job of communicating that message in the future. Now, back to hacking on darcs! Thanks, Jason

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ANN: Haskore tutorial (programming music using Haskell)
by jinjing 09 Aug '08

09 Aug '08

Hi there, Here's the project link: http://github.com/nfjinjing/haskore-guide/tree/master/doc/index.markdown I found Haskore pretty fun :) so I'm documenting it while learning it. Please don't hesitate to give suggestions / corrections. Questions: * How much music theory should be there ? ( I'm gonna learn those anyway ) * What kind of examples would be cool ? regards, jinjing

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