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ANNOUNCE: xmonad 0.2
by Spencer Janssen 31 May '07

31 May '07

The xmonad dev team is pleased to announce the 0.2 release of: xmonad: a tiling window manager http://xmonad.org About: Xmonad is a tiling window manager for X. Windows are arranged automatically to tile the screen without gaps or overlap, maximising screen use. All features of the window manager are accessible from the keyboard: a mouse is strictly optional, greatly increasing productivity in X. Xmonad is written and extensible in Haskell, and custom layout algorithms, and other extesions, may be implemented by the user in config files. Layouts may be applied dynamically, and separate layouts can be used on each workspace. A guiding principle of the user interface is predictability: users should know in advance precisely the window arrangement that will result from any action, leading to an intuitive user interface. Features: * Automatic window tiling and management * First class keyboard support: a mouse is unnecessary * Full multihead/Xinerama support * XRandR support to rotate, add or remove monitors * Per-workspace layout algorithms * Per-screen non-built in status bars, with arbitrary geometry * Dynamic restart/reconfigure preserving workspace state * Tiny code base (~500 lines of Haskell) * Fast, small and simple. No interpreters, no heavy extension languages Since 0.1, the following notable features and bug fixes have appeared: New features: * XRandR support, for dynamically adding, removing or rotating monitors * State-preserving dynamic restart * Popup, customisable status bar support * Multiple clients may appear in the master pane * mod-shift-j/k, to swap windows with their neighbours * mod-n, to resize windows * User-specified layout algorithms may be written in config files * All layouts may be 'mirrored' (rotated) * configurable window border size and colour Design changes: * Reimplemented core of xmonad with a 'zipper' data type to track focus by construction. We believe this is a first. * Use of Neil Mitchell's 'catch' program to verify pattern match safety * Use of ReaderT and StateT to partition read-only and modifiable values * Custom layout messages handled with open data type simulation * More QuickCheck properties Bug fixes: * numlock handling is fixed More information, screenshots, documentation and community resources are available from: http://xmonad.org Xmonad is available from hackage, and via darcs. Happy hacking! The Xmonad Team: Spencer Janssen Don Stewart Jason Creighton Xmonad has also received patches from: Alec Berryman Chris Mears Daniel Wagner David Glasser David Lazar David Roundy Joe Thornber Miikka Koskinen Neil Mitchell Nick Burlett Robert Marlow Sam Hughes Shae Erisson

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Distributing a program with support files
by Neil Mitchell 30 May '07

30 May '07

Hi, I'm wanting to release a Haskell program, but am confused how I should distribute the associated files it needs. On Windows I would use the functions to find the path of the executable, and find the support files relative to that - in Haskell (because of Linux) that isn't the case. The basic setup I have is: foo.exe - main binary library.hs - required by the binary examples\*.hs - a massive tree of examples, which can be used by the binary foo.exe also needs to create temporary files relative to library.hs and the examples. Thanks Neil

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Re: [Haskell] ST vs State
by Bulat Ziganshin 30 May '07

30 May '07

Hello Federico, Wednesday, May 30, 2007, 12:54:35 PM, you wrote: > Control.Monad.ST > And > Control.Monad.State ST monad is just reduced IO monad which like IO organizes sequential (imperative) ordr of execution but unlike IO supports only a small closed set of operations - those working with STRef and STArray State monad provides just two operations - get and put, which provides access to some "monad state". unlike ST/IO monads operations in State monad (and all other monads) can be performed in any order as typical for lazy computations. of course, there are guarantees that put operation will be performed before get that reads appropriate state you may be interested looking at http://haskell.org/haskellwiki/IO_inside although it doesn't say about ST/State monads directly (btw, there is also Lazy.ST monad but it is not used too much :) -- Best regards, Bulat mailto:Bulat.Ziganshin@gmail.com

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Re: [Haskell-cafe] The C Equiv of != in Haskell (Apologies)
by PR Stanley 30 May '07

30 May '07

>>However, I don't think these other individuals had any business >>poking their hooters into this. > >If you don't want other individuals "poking their hooters" in what you >write, I recommend you to avoid sending open questions to public >mailing lists. yes, I was indeed referring to you and your large beak over which you clearly have no control. Nobody invited you to this discussion and as you can see I have already apologized to Neil for the misunderstanding. Yet, you seem to be desperate to keep the thread alive. Uh, save me from the ...

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Data.Generics
by mark＠ixod.org 30 May '07

30 May '07

Do we have a simple example somewhere of how to use gzipWithQ ? I can get things like everything and everywhere working with mkQ and mkT, but I can't work out how to make a curried query thing for gzipWithQ - I'm sure I'm missing the obvious. -- Mark

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Efficiency question
by Evil Bro 30 May '07

30 May '07

I'm pretty new to Haskell, so forgive me if my question is due to my non-functional way of thinking... I have the following code: module Main where main = print solution solution = solve 1000000 solve d = countUniqueFractions d 2 1 0 canBeSimplified (a,b) = gcd a b > 1 countUniqueFractions stopD currentD currentN count | currentD > stopD = count | currentN == currentD = countUniqueFractions stopD (currentD + 1) 1 count | canBeSimplified (currentN, currentD) = countUniqueFractions stopD currentD (currentN+1) count | otherwise = countUniqueFractions stopD currentD (currentN+1) (count + 1) When I run this code, I get a stack overflow. I don't understand why. Could anyone explain please? -- View this message in context: http://www.nabble.com/Efficiency-question-tf3823154.html#a10823572 Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com.

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System.Timeout problems
by Neil Mitchell 30 May '07

30 May '07

Hi I'm using the System.Timeout module from base, copied into my local repo, so that I can work with GHC 6.6.1. My copy is at: http://www.cs.york.ac.uk/fp/darcs/catch/catch_1/System/TimeoutGHC.hs (but it is identical to the one in base) Sadly, it doesn't seem to work for me. Here are the tests I've been using, the results I get, and what I would have liked. All are GHC 6.6 on Windows. -- TEST 1 import System.TimeoutGHC main :: IO () main = do r <- timeout (5 * 10^6) (putStrLn "here") print r Without -threaded: here >> Just () >> wait 5 seconds Without -threaded: here >> wait 5 seconds >> Just () So, either way, I get a 5 second delay - not something I want. -- TEST 2 import System.TimeoutGHC main :: IO () main = do r <- timeout (length [1..]) (putStrLn "here") print r Now, with either -threaded, or without, it never terminates. Basically I can't get the timeout to do anything I would like with any flags. Can someone come to my rescue? Am I getting timeout wrong? Thanks Neil

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Shared libraries in GHC
by Georg Sauthoff 30 May '07

30 May '07

Hi, while searching, if ghc can create packages as shared libraries I found a ticket with a kind of non-accepted status: http://hackage.haskell.org/trac/summer-of-code/ticket/46 But at the google SoC page it looks like an accepted project: http://code.google.com/soc/haskell/appinfo.html?csaid=D0137F8B637176F1 Well what is the status of the project? Does the student have a blog/webpage where one can track the progress of the project? Btw, the problem I want to solve with shared libraries is the case, where I want to program 2 frontends (==2 executables), which share a lot of Haskell-Code. I am afraid, if both frontends are linked statically, the result will look a bit 'bloated' ... Best regards Georg Sauthoff

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Is there a Template lib like Cheetah in python?
by Albert Lee 30 May '07

30 May '07

I am writing some webpage using haskell, I know Xhtml, but I also need some other persons to write simple htmls so I need a template system like cheetah in python, but I didn't find anything through google. any help? -- http://www.kamang.net

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ffi linking problem
by jeff p 30 May '07

30 May '07

Hello, Can anyone give me some tips concerning the following error: myPrompt> ghc --make -fffi f.hs -l mylib.lib ghc --make -fffi f.hs -l mylib.lib [1 of 1] Compiling Main ( f.hs, f.o ) Linking f.exe ... d:\ghc\ghc6.6\gcc-lib\ld.exe: cannot find -l-Ld:/ghc/ghc6.6 collect2: ld returned 1 exit status thanks, Jeff

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