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Re: [darcs-users] Poll: Do you need to be able to build darcs from source on GHC 6.6?
by Juliusz Chroboczek 31 Oct '08

31 Oct '08

> Also, note that Lenny has 6.8, and it is scheduled to become stable Real > Soon Now. That's irrelevant. Lenny going stable will not cause my servers to automatically get upgraded. FWIW, the experimental server is scheduled to switch to lenny in the summer of 2009. There is no ETA for the production servers, which tend to be managed more conservatively still. Juliusz

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Cabal packaging problem - Build-Depends name for Network.Curl.Download?
by Brian Troutwine 31 Oct '08

31 Oct '08

Hello all, I'm having a small bit of trouble using cabal to package a program I'm calling aule. I cannot build the program using cabal but can compile it using ghc directly. Here's my aule.config: Name: Aule Version: 0.2.0 Cabal-Version: >= 1.2 Build-type: Simple Author: Brian L. Troutwine Maintainer: goofyheadedpunk(a)gmail.com Stability: alpha Executable aule Build-Depends: base, network, bytestring, download-curl Main-Is: Main.hs Hs-Source-Dirs: src ghc-options: -Wall -O2 If I decend into src/ the result is as follows. blt@doritos:~/aule/src $ ghc -Wall -O2 --make Main.hs [1 of 1] Compiling Main ( Main.hs, Main.o ) Linking Main ... If I attempt to use cabal the result is the following. blt@doritos:~/aule $ runhaskell Setup.hs configure --prefix=$HOME Configuring Aule-0.2.0... Setup.hs: At least the following dependencies are missing: download-curl -any I've attempted variations on the download-curl name, as well. Also, download-curl was install using the nifty cabal-install tool. I run Ubuntu 8.04 with ghc 6.8.2. Thanks, Brian

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Re: Problems with Windows
by Felix Martini 30 Oct '08

30 Oct '08

Hi John, You don't have to compile hsc2hs yourself. It is part of the standard GHC installation. Cabal should be able to find it. You can check if it does by running runghc Setup.hs configure -v when configuring a package. Compiling network-2.2.0.0 against parsec-3.0.0 with msys/mingw worked fine for me. So if Cabal cannot find hsc2hs you could reinstall GHC or otherwise try to compile network-2.2.0.0 with msys. Regards, Felix

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LAST CALL: Haskell Communities and Activities Report
by Janis Voigtlaender 30 Oct '08

30 Oct '08

Dear Haskellers, It is not yet too late to contribute to the 15th edition of the HC&A Report. In fact, I will wait for a few more days. If you haven't already, please write an entry for your new project or update your old entry. Please mail your entries to hcar(a)haskell.org in plain text or LaTeX format. More information can be found in the original Call for Contributions at http://www.haskell.org/pipermail/haskell/2008-October/020651.html I look forward to receiving your contributions. Thanks a lot, Janis (current editor) -- Dr. Janis Voigtlaender http://wwwtcs.inf.tu-dresden.de/~voigt/ mailto:voigt@tcs.inf.tu-dresden.de

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RE: [Haskell] Making 'Super Nario Bros.' in Haskell‏
by Eli Ford 30 Oct '08

30 Oct '08

That’s great -- easy to follow, even though I can’t read the comments. ^^ It’s not possible for actors to ‘watch’ each other in this system, correct? For instance, if one actor holds a reference to another, it will keep that old version of the actor alive, but it won’t see when the actor moves. This game doesn’t seem to need actors that watch each other, but it’s very common in games. I’ve been using IORefs for that purpose, but I like how pure the Mario game is. Is there a better way than IORefs? ________________________________ From: haskell-bounces(a)haskell.org [mailto:haskell-bounces@haskell.org] On Behalf Of Korcan Hussein Sent: Wednesday, October 29, 2008 4:57 PM To: haskell(a)haskell.org Subject: [Haskell] Making 'Super Nario Bros.' in Haskell‏ Hi I haven't seen this posted any where so I'm sorry in advance if this has been mentioned already but I came across this recent video on youtube: http://uk.youtube.com/watch?v=gVLFGQGRsDw it's a mario clone written in haskell with a link to source code repository (http://svn.coderepos.org/share/lang/haskell/nario/) I thought that it maybe useful to some people. Trustworthiness: Vendor reliability: Privacy: Child safety: ________________________________ For the best free wallpapers from MSN Click here! <http://wallpapers.msn.com/?ocid=%5bB001MSN42A0716B%5d>

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Hugs GraphicsUtils "legacy" code
by Galchin, Vasili 30 Oct '08

30 Oct '08

Hello, What is the suggested migration path from the Hugs GraphicsUtils to contemporary Haskell?? Thanks, Vasili

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[Somewhat OT] Speed
by Andrew Coppin 30 Oct '08

30 Oct '08

Hi guys. This isn't specifically to do with Haskell, but... does anybody have any idea roughly how fast various CPU operations are? For example, is integer arithmetic faster or slower than floating-point? Is addition faster or slower than multiplication? How much slower are the trigonometric functions? etc. Does using 8-bit integers make arithmetic any faster than using wider values? Does anybody have a good resource for this kind of information?

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Problems with Windows
by John Van Enk 30 Oct '08

30 Oct '08

Hello All, I'm trying to reinstall network-2.2.0.0 against Parsec 3 in Windows. Well, this is really hard/impossible to do. Here's what I've done so far: 1) After bashing my face against my desk for a while, I got cabal-install installed in windows. 2) cabal install network --reinstall 3) This freaks out because I don't have hsc2hs installed, but it doesn't tell me that, it just complains about something having to do with sizeof. 4) I figure out that I need hsc2hs installed, and i put cabal-install to use fetching it for me. 5) cabal-install fails because hsc2hs needs the process and directory packages, but they aren't exposed by the cabal file (at least in the version sitting on hackage, I assume this is the right one to use). 6) I give up on using cabal-install to get hsc2hs, so i download the targz for hsc2hs directly. 7) I fix the .cabal file to include process and directory 8) runhaskell Setup configure: >runhaskell Setup configure Configuring hsc2hs-0.67.20061107... Warning: No 'build-type' specified. If you do not need a custom Setup.hs or ./configure script then use 'build-type: Simple'. 9) runhaskell Setup build: Everything works fine. 10) runhaskell Setup install: Everything works fine. 11) Go back to try and install network-2.2.0.0 again with cabal-install. 12) Gets past the sizeof/hsc2hs errors, but then chokes on spaces in build path names: Preprocessing library network-2.2.0.0... gcc.exe: Files\Haskell\parsec-2.1.0.1\ghc-6.8.3: No such file or directory linking dist\build\Network\BSD_hsc_make.o failed command was: C:\ghc\ghc-6.8.3\gcc.exe -BC:\ghc\ghc-6.8.3\gcc-lib -IC:\ghc\ghc-6.8.3\include\mingw -LC:\Program Files\Haskell\parsec-2.1.0.1\ghc-6.8.3 -LC:\ghc\ghc-6.8.3/lib\base-3.0.2.0 -lwsock32 -lmsvcrt -lkernel32 -luser32 -lshell32 -LC:\ghc\ghc-6.8.3 -LC:\ghc\ghc-6.8.3/gcc-lib -lm -lgmp -lwsock32 dist\build\Network\BSD_hsc_make.o -o dist\build\Network\BSD_hsc_make.exe cabal: Error: some packages failed to install: network-2.2.0.0 failed during the building phase. The exception was:exit: ExitFailure 1 13) And this is where I finally gave up and came here. Does any one have any insight into: 1) Why cabal doesn't check for hsc2hs during a configure 2) How I can rebuild network-2.2.0.0 on my Windows box without sacrificing a goat to Bill Gates/GHC Gods? Thanks. /jve

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Re: [Haskell] How to get the binary respentation of the Int/Double.
by Ryan Ingram 29 Oct '08

29 Oct '08

Actually, this is a good question, at least as relating to floating point values. Is there a primitive to view the machine representation of floats? I'm thinking of functions like: reinterpretFloatAsWord :: Float -> Word32 reinterpretWordAsFloat :: Word32 -> Float reinterpretDoubleAsWord :: Double -> Word64 reinterpretWordAsDouble :: Word64 -> Double There are decodeFloat and encodeFloat in the RealFloat class, but these seem to be a bit heavy for inner-loop usage, especially when you are just going to paste the values back together into a word immediately anyways. Are the precision of Float and Double specified by the standard? There's actually lots of nice tricks you can do with these functions; for example, if you know you have a floating point value between 0 and 2^23-1, you can convert it to integer with a floating point add and an integer mask: > magic = 0x00800000 :: Float -- 2^23 > magicMask = 0x007fffff :: Word32 -- 2^23 - 1 > fastFloatToInt23 :: Float -> Word32 > fastFloatToInt23 x = reinterpretFloatAsWord (x + magic) .&. magicMask The add sets the exponent of the float to +23 and arranges it so the low bit of the float corresponds to "1", rounding if necessary. Then you can interpret the result as an integer and mask off the exponent and sign bit from the float, leaving you with just the integer value. This relies on the representation of IEEE single-precision floats, of course. These sorts of tricks come have in handy when working on graphics code; often I've found myself wanting to index into an array with the nearest value after some floating point computation. Texture mapping hardware does this conversion all the time, for example, and sometimes it's useful to emulate that behavior in software. -- ryan On Tue, Oct 28, 2008 at 10:08 AM, Brandon S. Allbery KF8NH <allbery(a)ece.cmu.edu> wrote: > On 2008 Oct 28, at 10:38, haihualin wrote: >> >> I am wondering how to get the binary respentation of the Int/Double. >> So I can save the integer as the binary data so that the C program can >> read it from the file. > > > The Binary package on Hackage (http://hackage.haskell.org) allows you to > serialize Haskell data in any form including C-compatible binary output. > > -- > brandon s. allbery [solaris,freebsd,perl,pugs,haskell] allbery(a)kf8nh.com > system administrator [openafs,heimdal,too many hats] allbery(a)ece.cmu.edu > electrical and computer engineering, carnegie mellon university KF8NH > > > _______________________________________________ > Haskell mailing list > Haskell(a)haskell.org > http://www.haskell.org/mailman/listinfo/haskell >

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How to use lib compat-base3 in ghc 6.10?
by Magicloud 29 Oct '08

29 Oct '08

Hi, Xmonad needs Data.Generics from base3. And I found out that there is a "compat-base3" in ghc 6.10, which has Data.Generics. But `ghc -v` reports that base-3.0.3.0 is hidden. So I wonder how could I compile Xmonad with ghc 6.10? Thanks.

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