Re: [Haskell-cafe] Help on using System.Win32.Com.Automation
Hi Wilkes,
you may want to have a look at a simple example of how to
interop with Windows WMI using the COM package at --
http://haskell.forkio.com/com-examples
Hope it is of some help to you.
--sigbjorn
On 3/19/2009 16:49, Wilkes Joiner wrote:
I'm playing around with the com package, but I'm having a hard time
understanding how to map a COM call to the appropriate methodN or
functionN call. Does anyone have any example code that uses the
method1 or higher. Any help or pointers would be appreciated.
Here's the code I have so far:
import System.Win32.Com
import System.Win32.Com.Automation
dsn = Provider=vfpoledb.1;Data Source=C:\\SomeDirectory\\
main = coInitialize
openConnection = \con -
closeConnection con
openDSN :: String - IDispatch a - IO ()
openDSN dsn con = method0 Open [inString dsn] con
openConnection :: IO (IDispatch a)
openConnection = createObject ADODB.Connection = \con - openDSN
dsn con return con
closeConnection :: IDispatch a - IO ()
closeConnection = method0 Close []
{-
Wraps ADO Connection.Execute
http://msdn.microsoft.com/en-us/library/ms675023(VS.85).aspx
Set recordset = connection.Execute (CommandText, RecordsAffected, Options)
execute :: String - IDispatch a - IO a
execute cmd con = method1 Execute [inString cmd] (inEmpty,resWord64) con
-}
Thank You,
Wilkes
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[Haskell-cafe] MissingH bracketCD (aka bracketCWD) bug -- this is the infamous lazy io, right?
I got bitten by a bug (well, I call it bug) in bracketCD from HSH/MissingH demonstrated by the following code bracketCD is very useful for sysadminny one-offs, I use it all the time, but. I suspect that unless people are very careful, this behavior will affect other users of bracketCD, in potentially very subtle and tricky ways. 1) -- is there a more elegant way to deal with lazy io than the hack below? (putStrLn the last character) 2) -- should MissingH function bracketCD be fixed, and if so how? import System.FilePath.Find (find) import System.Directory (getDirectoryContents, getCurrentDirectory, setCurrentDirectory) import System.Path (bracketCWD) -- from MissingH -- the fixed function, a more restrictive type than bracketCWD which lets you do any io, not just showables myBracketCWD :: Show a = FilePath - IO a - IO a myBracketCWD fp action = do oldcwd - getCurrentDirectory setCurrentDirectory fp a - action putStrLn $ show . last . show $ a -- force evaluation setCurrentDirectory oldcwd return a -- rather than listing /, lists dir this module is in tWrong = bracketCWD / $ return . take 2 = listCurrentWithFind -- this lists filesystem root tRight = myBracketCWD / $ return . take 2 = listCurrentWithFind listCurrentWithFind = System.FilePath.Find.find (return True) (return True) . -- for some reason, bracketCWD does the right thing with get tGetContents = myBracketCWD / $ return . take 2 = getDirectoryContents . Actual code for bracketCWD in MissingH: -- this is from MissingH, seems there's a bug when attempt to wrap a find command bracketCWD :: FilePath - IO a - IO a bracketCWD fp action = do oldcwd - getCurrentDirectory setCurrentDirectory fp finally action (setCurrentDiurectory oldcwd) ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Help on using System.Win32.Com.Automation
Sigbjorn Finne wrote:
Hi Wilkes,
you may want to have a look at a simple example of how to
interop with Windows WMI using the COM package at --
http://haskell.forkio.com/com-examples
I try compile WMIDemo.hs but recive error:
[code]
c:\htestghc --make WMIDemo.hs
[2 of 2] Compiling WMIDemo ( WMIDemo.hs, WMIDemo.o )
WMIDemo.hs:24:2:
Couldn't match expected type `[a]' against inferred type `(a1, b)'
In the pattern: (_, ls)
In a stmt of a 'do' expression: (_, ls) - is # enumVariants
In the second argument of `($)', namely
`do obj - Auto.getObject winmgmts:.\\root\\CIMV2
is - obj
# instancesOf
Win32_OperatingSystem
(Nothing :: Maybe Int)
(Nothing :: Maybe (IDispatch ()))
(_, ls) - is # enumVariants
case ls of {
[]
- fail Hmm..no OS information available; expected at
least one.
(wmi_os : _) - do ... }'
[/code]
ghc 6.10.1
com-1.2.1
Windows Vista Home Ru + sp1
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Re: [Haskell-cafe] MissingH bracketCD (aka bracketCWD) bug -- this is the infamous lazy io, right?
Excerpts from Thomas Hartman's message of Mon Mar 23 09:08:41 +0100 2009: I got bitten by a bug (well, I call it bug) in bracketCD from HSH/MissingH demonstrated by the following code bracketCD is very useful for sysadminny one-offs, I use it all the time, but. I suspect that unless people are very careful, this behavior will affect other users of bracketCD, in potentially very subtle and tricky ways. 1) -- is there a more elegant way to deal with lazy io than the hack below? (putStrLn the last character) Yes without changing the bracketCD function you can use a strict 'return' function to help you avoid leaks. return' :: (Monad m, NFData sa) - sa - m sa return' x = rnf x `seq` return x 2) -- should MissingH function bracketCD be fixed, and if so how? Not completely while staying in the full 'IO' monad. Have a look at the strict-io package [1] that goes in this direction. myBracketCWD :: (NFData sa, Show sa) = FilePath - SIO sa - IO sa myBracketCWD fp action = do oldcwd - getCurrentDirectory setCurrentDirectory fp a - SIO.run action rnf a `seq` setCurrentDirectory oldcwd return a The same function could be more deeply in the 'SIO' monad by returning in the 'SIO' monad. However this would require to first wrap getCurrentDirectory and setCurrentDirectory in the 'SIO' monad. Best regards, [1]: http://hackage.haskell.org/cgi-bin/hackage-scripts/package/strict-io -- Nicolas Pouillard ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] [ANN] Safe Lazy IO in Haskell
Excerpts from Henning Thielemann's message of Sun Mar 22 23:58:44 +0100 2009: On Sun, 22 Mar 2009, nicolas.pouillard wrote: It sounds like a nice idea, it would be great to have a straight-io package to play a bit more with explicit exceptions in things like 'IO'. Maybe I should then restrict lifting to LazyIO to SIO actions. That would not make LazyIO safe, but reduces surprises. By SIO you actually mean straight-io right? I was confused because I also have an SIO monad in the strict-io package. -- Nicolas Pouillard ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] HSTringTemplate and syb-with-class
Hello all, I'm trying to use the generic capabilities of HSTringTemplate. The documentation claims that the package is able to automatically generate instances of ToSElem if syb-with-class is installed but gives no further details. I installed syb-with-class and then installed HSTringTemplate with additional configure parameter syb-with-class=True. But when I import Text.StringTemplate.GenericWithClass and then try deriving ToSElem or $(derive ToSElem), I just get an error like Can't make a derived instance of `ToSElem Any suggestions or pointer to further docs? Kind regards Torsten ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] [ANN] Safe Lazy IO in Haskell
On Mon, 23 Mar 2009, nicolas.pouillard wrote: Excerpts from Henning Thielemann's message of Sun Mar 22 23:58:44 +0100 2009: On Sun, 22 Mar 2009, nicolas.pouillard wrote: It sounds like a nice idea, it would be great to have a straight-io package to play a bit more with explicit exceptions in things like 'IO'. Maybe I should then restrict lifting to LazyIO to SIO actions. That would not make LazyIO safe, but reduces surprises. By SIO you actually mean straight-io right? Yes I was confused because I also have an SIO monad in the strict-io package. Sorry ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] [ANN] Safe Lazy IO in Haskell
Excerpts from Henning Thielemann's message of Mon Mar 23 11:06:20 +0100 2009: On Mon, 23 Mar 2009, nicolas.pouillard wrote: Excerpts from Henning Thielemann's message of Sun Mar 22 23:58:44 +0100 2009: On Sun, 22 Mar 2009, nicolas.pouillard wrote: It sounds like a nice idea, it would be great to have a straight-io package to play a bit more with explicit exceptions in things like 'IO'. Maybe I should then restrict lifting to LazyIO to SIO actions. That would not make LazyIO safe, but reduces surprises. By SIO you actually mean straight-io right? Yes Then what do you mean by lifting to LazyIO to SIO actions? Do you mean liftSIO :: SIO a - LazyIO.T a which says that we only lift computations that explicitly throws exceptions. In that case it be actually safer, but all of this greatly depends on how reasonable is the explicit exception handling. In particular in the case 'IO', using explicit exception is maybe too heavy. -- Nicolas Pouillard ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] [ANN] Safe Lazy IO in Haskell
On Mon, 23 Mar 2009, nicolas.pouillard wrote: Excerpts from Henning Thielemann's message of Mon Mar 23 11:06:20 +0100 2009: Yes Then what do you mean by lifting to LazyIO to SIO actions? Do you mean liftSIO :: SIO a - LazyIO.T a which says that we only lift computations that explicitly throws exceptions. Yes. In that case it be actually safer, but all of this greatly depends on how reasonable is the explicit exception handling. If it does not fit, you can change it. :-) That's the advantage over built-in IO exceptions. In particular in the case 'IO', using explicit exception is maybe too heavy. I think it's precisely the best thing to do, given all the problems with asynchronous, imprecise and what-know-I exceptions. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] ANNOUNCE: WinGhci, a GUI for GHCI on Windows
Hi, I am pleased to announce the first release of WinGhci.
WinGhci is a simple GUI for GHCI on Windows. It is closely based on WinHugs,
and provides similar functionality.
WinGhci project web page:
http://code.google.com/p/winghci/mhtml:{5097F7F7-AA40-4661-A7CF-D5EEC38F084A}mid://0003/!x-usc:http://code.google.com/p/winghci/
Binaries:
http://winghci.googlecode.com/files/WinGhci-1.0-bin.zipmhtml:{5097F7F7-AA40-4661-A7CF-D5EEC38F084A}mid://0003/!x-usc:http://winghci.googlecode.com/files/WinGhci-1.0-bin.zip
Sources:
http://winghci.googlecode.com/files/WinGhci-1.0-src.zipmhtml:{5097F7F7-AA40-4661-A7CF-D5EEC38F084A}mid://0003/!x-usc:http://winghci.googlecode.com/files/WinGhci-1.0-src.zip
Acknowledgements
Much of the code in WinGhci was taken from the Winhugs project. Many thanks
to Neil Mitchell for giving us permission to use his code.
mhtml:{5097F7F7-AA40-4661-A7CF-D5EEC38F084A}mid://0003/!x-usc:http://winghci.googlecode.com/files/WinGhci-1.0-bin.zip
Pepe Gallardo
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[Haskell-cafe] Hackage upload problems?
Hello, Currently I'm trying to upload a minor update of Salvia to Hackage to fix some dependency issues but Hackage times out all the time? Both the CLI tool and the web-interface do not react to my upload request. Any known problems here? Gr, Sebastiaan. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Use unsafePerformIO to catch Exception?
Hi, I just feel it is not comfortable to deal with exceptions only within IO monad, so I defined tryArith :: a - Either ArithException a tryArith = unsafePerformIO . try . evaluate and it works quite good as map (tryArith . (div 5)) [2,1,0,5] evaluates to [Right 2,Right 5,Left divide by zero,Right 1] However, I guess unsafePerformIO definitely has a reason for its name. As I read through the document in System.IO.Unsafe, I can't convince myself whether the use of 'tryArith' is indeed safe or unsafe. I know there have been a lot of discussion around unsafePerformIO, but I still can't figure it out by myself. Can someone share some thoughts on this particular use of unsafePerformIO? Is it safe or not? And why? Thanks, Xiao-Yong -- c/*__o/* \ * (__ */\ ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: SoC idea: interactive profiling
Hello, On Sun, Mar 22, 2009 at 04:08:59PM +0100, Alex Ott wrote: May be providing profiling information for kcachegrind will be a good solution? For example, there are tools for PHP, that allow to view collected information in kcachegrind, and get interactive zooming, etc. This is really awesome idea, you're totally not alone who would want this! -- Tomáš Janoušek, a.k.a. Liskni_si, http://work.lisk.in/ ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: Use unsafePerformIO to catch Exception?
You should ensure that the result of evaluate is in normal form, not just weak head normal form. You can do this with the Control.Parallel.Strategies module: import Control.Exception(ArithException(..),try,evaluate) import Control.Parallel.Strategies(NFData,using,rnf) import System.IO.Unsafe(unsafePerformIO) tryArith :: NFData a = a - Either ArithException a tryArith = unsafePerformIO . try . evaluate . flip using rnf test :: [Either ArithException Integer] test = map (tryArith . (div 5)) [2,1,0,5] testResult = [Right 2,Right 5,Left DivideByZero,Right 1] withPair :: Integer - (Integer,Integer) withPair x = (x,throw Overflow) main = do print (test == testResult) print (tryArith (withPair 7)) print (tryArith' (withPair 7)) in ghci *Main main main True Left arithmetic overflow Right (7,*** Exception: arithmetic overflow This rnf :: Strategy a ensures that the result of evaluate is in normal form. This means it should not have any embedded lazy thunks, so any errors from such thunks will be forced while in the scope of the try. Otherwise a complex type like the result of withPair can hide an error. Xiao-Yong Jin wrote: Hi, I just feel it is not comfortable to deal with exceptions only within IO monad, so I defined tryArith :: a - Either ArithException a tryArith = unsafePerformIO . try . evaluate and it works quite good as map (tryArith . (div 5)) [2,1,0,5] evaluates to [Right 2,Right 5,Left divide by zero,Right 1] However, I guess unsafePerformIO definitely has a reason for its name. As I read through the document in System.IO.Unsafe, I can't convince myself whether the use of 'tryArith' is indeed safe or unsafe. I know there have been a lot of discussion around unsafePerformIO, but I still can't figure it out by myself. Can someone share some thoughts on this particular use of unsafePerformIO? Is it safe or not? And why? Thanks, Xiao-Yong ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: ANNOUNCE: WinGhci, a GUI for GHCI on Windows
This is wonderful--just what I was waiting for! The application looks beautiful, and I'm very happy that GHCi now has a matching GUI application along the lines of WinHugs. It would be even better if you could provide some installation/uninstallation information. I unzipped the contents of WinGhci-1.0-bin.zip into the C:\Documents and Settings\username\My Documents\ folder, but there was no README file. Therefore, I simply ran Install.exe, and pressed Yes at the question to associate file extensions with winghci.exe. After some thought, I then decided that installing the application in the C:\Program Files\ folder would be better, but could not find any information on how to uninstall the application, so I just moved the folder and then re-ran Install.exe, again pressing Yes at the question to associate file extensions with winghci.exe. Is this the correct way to reinstall the application? Then, I ran StartGHCI.exe, but nothing seemed to happen, so I then ran winghci.exe, and the application started. Is this the correct way to start the application? I tried to check the winghci Wiki at http://code.google.com/p/winghci/w/list, but the project had no wiki pages. -- Benjamin L. Russell -- Benjamin L. Russell / DekuDekuplex at Yahoo dot com http://dekudekuplex.wordpress.com/ Translator/Interpreter / Mobile: +011 81 80-3603-6725 Furuike ya, kawazu tobikomu mizu no oto. -- Matsuo Basho^ ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] least fixed points above something
On Friday 20 March 2009 5:23:37 am Ryan Ingram wrote:
On Fri, Mar 20, 2009 at 1:01 AM, Dan Doel dan.d...@gmail.com wrote:
However, to answer Luke's wonder, I don't think fixAbove always finds
fixed points, even when its preconditions are met. Consider:
f [] = []
f (x:xs) = x:x:xs
twos = 2:twos
How about
fixAbove f x = x `lub` fixAbove f (f x)
Probably doesn't work (or give good performance) with the current
implementation of lub :)
But if lub did work properly, it should give the correct answer for
fixAbove f (2:undefined).
This looked good to me at first, too (assuming it works), and it handles my
first example. But alas, we can defeat it, too:
f (x:y:zs) = x:y:x:y:zs
f zs = zs
Now:
f (2:_|_) = _|_
f _|_ = _|_
fix f = _|_
fixAbove f (2:_|_) = 2:_|_ `lub` _|_ `lub` _|_ ...
= 2:_|_
Which is not a fixed point of f. But there are actually multiple choices of
fixed points above 2:_|_
f (2:[]) = 2:[]
forall n. f (cycle [2,n]) = cycle [2,n]
I suppose the important distinction here is that we can't arrive at the
fixed
point simply by iterating our function on our initial value (possibly
infinitely many times). I suspect this example won't be doable without an
oracle of some kind.
Ah well.
-- Dan
Thanks for all comments on my question, especially those bashing my poor
code.
The above approach does not apply to my case. What I have is a monotone
function f on a partial order satisfying f x = x, for all x. Given that the
partial order is in fact a cpo this is enough to guarantee that a least
fixed
point can be found above any point in the partial order simply by iterating
f, although not necessarily in finite time. Taking the lub of x and the
fixed
point of f (over bottom) need not give a fixed point even if one exists.
Think of reachability in a graph from a starting set. Let S be some fixed
set, and let f return all points reachable in 0 or 1 step from the union
of S and the argument to f. Then fix f is the set of points reachable from
S,
which is a fixed point. But adding some point x outside fix f will in
general
not give me a fixed point, even though a unique fixed point exists (the set
reachable from the union of {x} and fix f).
Jens
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[Haskell-cafe] Re: ANNOUNCE: WinGhci, a GUI for GHCI on Windows
Just another couple of thoughts for possible additional improvement: 1. It would be even nicer if WinGhci added a menu entry to the Start menu automatically, as WinHugs does. 2. For the proposed menu entry, it would also probably be a good idea if WinGhci added a folder for that menu entry, and included a link to a README file in there, as WinHugs does also. 3. In order to distinguish WinGhci from GHCi, it might also be helpful if WinGhci had a different icon; the current WinGhci icon is identical to the one for GHCi (perhaps use the forthcoming official Haskell logo here?). Just my two cents for now -- Benjamin L. Russell -- Benjamin L. Russell / DekuDekuplex at Yahoo dot com http://dekudekuplex.wordpress.com/ Translator/Interpreter / Mobile: +011 81 80-3603-6725 Furuike ya, kawazu tobikomu mizu no oto. -- Matsuo Basho^ ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: Use unsafePerformIO to catch Exception?
ChrisK hask...@list.mightyreason.com writes: You should ensure that the result of evaluate is in normal form, not just weak head normal form. You can do this with the Control.Parallel.Strategies module: import Control.Exception(ArithException(..),try,evaluate) import Control.Parallel.Strategies(NFData,using,rnf) import System.IO.Unsafe(unsafePerformIO) tryArith :: NFData a = a - Either ArithException a tryArith = unsafePerformIO . try . evaluate . flip using rnf test :: [Either ArithException Integer] test = map (tryArith . (div 5)) [2,1,0,5] testResult = [Right 2,Right 5,Left DivideByZero,Right 1] withPair :: Integer - (Integer,Integer) withPair x = (x,throw Overflow) main = do print (test == testResult) print (tryArith (withPair 7)) print (tryArith' (withPair 7)) in ghci *Main main main True Left arithmetic overflow Right (7,*** Exception: arithmetic overflow This rnf :: Strategy a ensures that the result of evaluate is in normal form. This means it should not have any embedded lazy thunks, so any errors from such thunks will be forced while in the scope of the try. Otherwise a complex type like the result of withPair can hide an error. Thanks a lot. I found it is much easier to deal with Exception with this than convert all my code to monadic style. -- c/*__o/* \ * (__ */\ ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: ANNOUNCE: WinGhci, a GUI for GHCI on Windows
Benjamin L.Russell wrote: This is wonderful--just what I was waiting for! The application looks beautiful, and I'm very happy that GHCi now has a matching GUI application along the lines of WinHugs. Indeed - me too ! It would be even better if you could provide some installation/uninstallation information. I unzipped the contents of WinGhci-1.0-bin.zip into the C:\Documents and Settings\username\My Documents\ folder, but there was no README file. And version information - I tried it with GHC 6.4 and it died (Not Responding) What version of GHCi does it require? And no, I won't upgrade GHC just yet (this is the latest GHC/wxHaskell combo that works for me with GHCi...) -- Andrew Butterfield Tel: +353-1-896-2517 Fax: +353-1-677-2204 Foundations and Methods Research Group Director. School of Computer Science and Statistics, Room F.13, O'Reilly Institute, Trinity College, University of Dublin http://www.cs.tcd.ie/Andrew.Butterfield/ ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] least fixed points above something
Am Montag, den 23.03.2009, 12:55 + schrieb Jens Blanck: The above approach does not apply to my case. What I have is a monotone function f on a partial order satisfying f x = x, for all x. Given that the partial order is in fact a cpo this is enough to guarantee that a least fixed point can be found above any point in the partial order which implies that every total value is a fixed point. simply by iterating f, although not necessarily in finite time. Since every total value is a fixed point of f, the infimum of all total values above x is an upper bound for the least fixed point above x. This upper bound can be found the following way: 1) Find a position p in x at which the value is bottom::T, such that type T has exactly one constructor. If there is no such position, you are ready. 2) If T has exactly one constructor, then replace the value at position p with that constructor, leaving the constructor arguments undefined for now. Go on with step 1. Let's call this upper bound y and assume a function glb that calculates the greatest lower bound of two values. Then you can 'frame' a value v into the interval [x, y] via the expression ((v `glb` y) `lub` x). This works, because y = x implies that (v `glb` y) and x have an upper bound in the CPO. Also, function f' v = ((f v `glb` y) `lub` x) is monotonic and expanding on the interval [x, y]. So we get: fixAbove f x = fix f' where f' v = (f v `glb` y) `lub` x y= ... -- see above Regards, Holger ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Sometimes I wish there was a global variable
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Rafael Cunha de Almeida wrote: | Hello, | | I am writing a OpenGL program in haskell, it can be found in: | http://github.com/aflag/galo/tree/master | But I hope this e-mail will be self-contained :). | | My main function goes like this: | (...) | rotX - newIORef (0.0::GLfloat) | rotY - newIORef (0.0::GLfloat) | pos - newIORef (0.0::GLfloat, 0.0, 0.0) | | displayCallback $= display (map f range) rotX rotY pos | | keyboardMouseCallback $= Just (keyboardMouse rotX rotY pos) | (...) | | Notice that rotX, rotY and pos are meant to be used as comunication | between the keyboardMouse and display functions. They need to be set as | 0 first, so display won't do anything. Only when they user press a few | buttons that those values change, so display behaves accordanly. | | In a state-based language I would place display and keyboardMouse in one | module and let them communcate to each other like they want. In haskell, | I'm not quite sure how to do it except by that parameter passing style. | | I thought about how state-monad may help with that. But I'm not sure how | I'd make the state variable to be contained inside a | display/keyboardMouse module. Another way to do this would be something like this: ~main = do ~ ... ~ displayCallback $= initialDisplayFunction ~ keyboardMouseCallback $= keyboardMouseFunction ~ ... ~keyboardMouseFunction = do ~ rotX - ... ~ rotY - ... ~ pos - ... ~ ... ~ displayCallback $= display ... rotX rotY rotZ You could even write your own state monad that does this callback reassignment for you (perhaps by wrapping StateT s IO a), then you can forget about all this explicit parameter passing. - - Jake -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.9 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAknHq+kACgkQye5hVyvIUKnX3ACeMLD8FLOTEya8can6veyp6cT3 ClMAnRdfl/DyOshvzlBF8QCtYgTf87fd =Bp4F -END PGP SIGNATURE- ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Hackage upload problems?
sfvisser: Hello, Currently I'm trying to upload a minor update of Salvia to Hackage to fix some dependency issues but Hackage times out all the time? Both the CLI tool and the web-interface do not react to my upload request. Any known problems here? Discussion taking place on libraries@ ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Hackage download and popularity statistics
For the first time, we've got download and popularity statistics from Hackage: http://www.galois.com/blog/2009/03/23/one-million-haskell-downloads/ Find out if your package made the top 100, and when we reach our 1 millionth hackage download! -- Don ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] RE: [ANN] Safe Lazy IO in Haskell
Nicolas Pouillard nicolas.pouillard at gmail.com writes: Hi folks, We have good news (nevertheless we hope) for all the lazy guys standing there. Since their birth, lazy IOs have been a great way to modularly leverage all the good things we have with *pure*, *lazy*, *Haskell* functions to the real world of files. We are happy to present the safe-lazy-io package [1] that does exactly this and is going to be explained and motivated in the rest of this post. Hi, Please let me know if I understood your code correctly. So, the SIO module is used only to ensure that the file processing is finished before the finalizer closes the file, right? In System.IO.Lazy.Input, run is defined as run :: NFData sa = LI sa - IO sa run = run' . fmap return' Can I change it to run = run' . fmap return ? I think the semantics is the same because run' will strictly force the processing anyway? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Help on using System.Win32.Com.Automation
Alexandr N. Zamaraev wrote: Sigbjorn Finne wrote: Hi Wilkes, you may want to have a look at a simple example of how to interop with Windows WMI using the COM package at -- http://haskell.forkio.com/com-examples I try compile WMIDemo.hs but recive error: [code] c:\htestghc --make WMIDemo.hs [2 of 2] Compiling WMIDemo ( WMIDemo.hs, WMIDemo.o ) WMIDemo.hs:24:2: Couldn't match expected type `[a]' against inferred type `(a1, b)' ... Hi, please upgrade to the latest version - 1.2.2 - of the com package for this example, http://hackage.haskell.org/cgi-bin/hackage-scripts/package/com There's been some improvements to the lib, esp. the handling of enumerations (which is where that type error is coming from.) hth --sigbjorn ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] A small display problem using Helium
Hello, I've written something simple: main:: IO () main= do lijn - getLine putStrLn lijn Now if I import it in Helium it will do the following: Test main test -- (here I'm typing test) test it will be displayed two times, why? Because it displays my input and the output of the function. Now I want to write a function that does NOT display my input, any suggestions how I can achieve this? Thanks in advance! ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] System.Random.Shuffle fix
I was looking for a shuffling algorithm to shuffle mp3-playlists so was very happy to see System.Random.Shuffle: http://hackage.haskell.org/cgi-bin/hackage-scripts/package/random-shuffle-0.0.2 However I get errors,non-exhaustive patterns in function shufleTree or extractTree depending how I call it. Errors are at the bottom. I fixed it but I don't have the math skills to see if I perhaps broke it statistically ... Here is my fix, someone (don't remember who, helped me a little): http://hpaste.org/fastcgi/hpaste.fcgi/view?id=2789#a2789 the shuffle at the end is with the fix. *Freet S.shuffle [1..10] [1..3] Loading package syb ... linking ... done. Loading package base-3.0.3.0 ... linking ... done. Loading package old-locale-1.0.0.1 ... linking ... done. Loading package old-time-1.0.0.1 ... linking ... done. Loading package random-1.0.0.1 ... linking ... done. Loading package random-shuffle-0.0.2 ... linking ... done. [2,4,6*** Exception: src\System\Random\Shuffle.hs:(52,6)-(55,30): Non-exhaustive patterns in function shuffleTree *Freet S.shuffle [1..3] [1..10] [2,*** Exception: src\System\Random\Shuffle.hs:(66,6)-(79,27): Non-exhaustive patterns in function extractTree *Freet :load c:/ghc/ghc-6.10.1/progs/Mp3Player/Shuffle.hs [1 of 1] Compiling Shuffle ( C:\ghc\ghc-6.10.1\progs\Mp3Player\Shuffle.hs, interpreted ) Ok, modules loaded: Shuffle. *Shuffle shuffle [1..3] [1..10] [2,1,3] *Shuffle shuffle [1..10] [1..3] [2,4,6*** Exception: C:\ghc\ghc-6.10.1\progs\Mp3Player\Shuffle.hs:(27,13)-(31,30): Non-exhaustive patterns in function shuffle' *Shuffle shuffle [1..10] [1..10] [2,4,6,8,10,3,9,7,5,1] *Shuffle ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] System.Random.Shuffle fix
friggin friggin ha scritto: I was looking for a shuffling algorithm to shuffle mp3-playlists so was very happy to see System.Random.Shuffle: http://hackage.haskell.org/cgi-bin/hackage-scripts/package/random-shuffle-0.0.2 However I get errors,non-exhaustive patterns in function shufleTree or extractTree depending how I call it. Errors are at the bottom. During building you should only get warnings. Non exhaustive patterns are ok, you hit them only if the input data is incorret. Probably in these cases, error should be used. I fixed it but I don't have the math skills to see if I perhaps broke it statistically ... Here is my fix, someone (don't remember who, helped me a little): http://hpaste.org/fastcgi/hpaste.fcgi/view?id=2789#a2789 the shuffle at the end is with the fix. *Freet S.shuffle [1..10] [1..3] Your input is not correct. If you read the source code (in a future version I'll add Haddock support): -- Given a sequence (e1,...en) to shuffle, and a sequence -- (r1,...r[n-1]) of numbers such that r[i] is an independent sample -- from a uniform random distribution [0..n-i], compute the -- corresponding permutation of the input sequence. I have added a convenience function `shuffle'`, where you just need to supply a random number generator. Note that the shuffle' function contains a bug; it should return the new random generator: shuffle' :: RandomGen gen = [a] - Int - gen - ([a], gen) I'm going to fix it in next version. [...] Regards Manlio ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Hugs on iPhone
I saw Miguel Mitrofanov ( http://www.nabble.com/Hugs-on-the-iphone-td19478992.html) successfully ported Hugs to the iPhone. I'm now wondering if anyone has tried to get Apple's blessing to put this in the App Store? It would be really great to be able to try out little Haskell ideas as the mood strikes. Of course, it's kind of essential to have an editor of some kind for more significant programs... Thanks, Kirk ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Hugs on iPhone
1) You'll need a terminal application first, and I'm not sure if there is one in AppStore. In fact, I AM sure there isn't. 2) My iPod Touch is still running 1.1.4 firmware; I've heard it's not that easy on 2.0 and later. 3) Personally, I'd love to see ghc on iPhone. It could even persuade me to upgrade. On 23 Mar 2009, at 21:00, Kirk Martinez wrote: I saw Miguel Mitrofanov (http://www.nabble.com/Hugs-on-the-iphone-td19478992.html ) successfully ported Hugs to the iPhone. I'm now wondering if anyone has tried to get Apple's blessing to put this in the App Store? It would be really great to be able to try out little Haskell ideas as the mood strikes. Of course, it's kind of essential to have an editor of some kind for more significant programs... Thanks, Kirk ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Hugs on iPhone
Unfortunately the developers agreement expressly forbids the use of interpreters that load and run external programs. This is probably for the simple reason that it would be almost impossible to secure, or even guarantee that it wont exceed its space and mem usage bounds required by AppStore apps. Short answer: Jailbreak and install away :) 2009/3/23 Kirk Martinez kirk.marti...@gmail.com I saw Miguel Mitrofanov ( http://www.nabble.com/Hugs-on-the-iphone-td19478992.html) successfully ported Hugs to the iPhone. I'm now wondering if anyone has tried to get Apple's blessing to put this in the App Store? It would be really great to be able to try out little Haskell ideas as the mood strikes. Of course, it's kind of essential to have an editor of some kind for more significant programs... Thanks, Kirk ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- We can't solve problems by using the same kind of thinking we used when we created them. - A. Einstein ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] SOC idea ticket: Rendering Engine
Hi! I've created a ticket for this idea: http://hackage.haskell.org/trac/summer-of-code/ticket/1572 Please write your opinion. I also put the source code here: http://code.google.com/p/lambdacube/ svn checkout *http*://lambdacube.googlecode.com/svn/trunk/lambdacube-read-only Cheers, Csaba Hruska ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Hugs on iPhone
On Mon, Mar 23, 2009 at 11:22 AM, Miguel Mitrofanov miguelim...@yandex.ruwrote: 1) You'll need a terminal application first, and I'm not sure if there is one in AppStore. In fact, I AM sure there isn't. There's SSH terminal programs like Putty based stuff that are in the AppStore. So that sort of thing has been done yes. 2) My iPod Touch is still running 1.1.4 firmware; I've heard it's not that easy on 2.0 and later. that's unfortunate. 3) Personally, I'd love to see ghc on iPhone. It could even persuade me to upgrade. On 23 Mar 2009, at 21:00, Kirk Martinez wrote: I saw Miguel Mitrofanov ( http://www.nabble.com/Hugs-on-the-iphone-td19478992.html) successfully ported Hugs to the iPhone. I'm now wondering if anyone has tried to get Apple's blessing to put this in the App Store? It would be really great to be able to try out little Haskell ideas as the mood strikes. Of course, it's kind of essential to have an editor of some kind for more significant programs... Thanks, Kirk ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Hugs on iPhone
On 23 Mar 2009, at 21:38, David Leimbach wrote: On Mon, Mar 23, 2009 at 11:22 AM, Miguel Mitrofanov miguelim...@yandex.ru wrote: 1) You'll need a terminal application first, and I'm not sure if there is one in AppStore. In fact, I AM sure there isn't. There's SSH terminal programs like Putty based stuff that are in the AppStore. So that sort of thing has been done yes. You sure it can SSH to iPhone itself? Installing Hugs (or GHC) on a desktop PC and connecting to it via ssh is anything but impressive. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Hugs on iPhone
I think he means a program running on the iPhone which allows you to open a terminal over an SSH session to other devices. The instance (I think) you're thinking of is where the SSH *server* runs on the iPhone. On Mon, Mar 23, 2009 at 2:46 PM, Miguel Mitrofanov miguelim...@yandex.ruwrote: On 23 Mar 2009, at 21:38, David Leimbach wrote: On Mon, Mar 23, 2009 at 11:22 AM, Miguel Mitrofanov miguelim...@yandex.ru wrote: 1) You'll need a terminal application first, and I'm not sure if there is one in AppStore. In fact, I AM sure there isn't. There's SSH terminal programs like Putty based stuff that are in the AppStore. So that sort of thing has been done yes. You sure it can SSH to iPhone itself? Installing Hugs (or GHC) on a desktop PC and connecting to it via ssh is anything but impressive. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- /jve ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] SOC idea ticket: Rendering Engine
* Csaba Hruska csaba.hru...@gmail.com [2009-03-23 19:24:19+0100] Hi! I've created a ticket for this idea: http://hackage.haskell.org/trac/summer-of-code/ticket/1572 Please write your opinion. I also put the source code here: http://code.google.com/p/lambdacube/ svn checkout *http*://lambdacube.googlecode.com/svn/trunk/lambdacube-read-only Hi Csaba, this looks very promising! Correct command to checkout: svn checkout http://lambdacube.googlecode.com/svn/trunk/ lambdacube -- Roman I. Cheplyaka :: http://ro-che.info/ Don't let school get in the way of your education. - Mark Twain ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Hugs on iPhone
On Mon, Mar 23, 2009 at 11:46 AM, Miguel Mitrofanov miguelim...@yandex.ruwrote: On 23 Mar 2009, at 21:38, David Leimbach wrote: On Mon, Mar 23, 2009 at 11:22 AM, Miguel Mitrofanov miguelim...@yandex.ru wrote: 1) You'll need a terminal application first, and I'm not sure if there is one in AppStore. In fact, I AM sure there isn't. There's SSH terminal programs like Putty based stuff that are in the AppStore. So that sort of thing has been done yes. You sure it can SSH to iPhone itself? Installing Hugs (or GHC) on a desktop PC and connecting to it via ssh is anything but impressive. It sure can't... but you said a terminal application, not a terminal on the iphone :-) If you meant you wanted a shell on the iPhone for that, that's something different, but if you wanted the ability to deal with terminal sessions from a serial-like stream, that does exist. I agree ssh'ng to another server isn't that interesting but someone just committed a GHCI GUI for windows... I thought Hugs had such a thing already. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Hugs on iPhone
On Mon, Mar 23, 2009 at 11:53 AM, John Van Enk vane...@gmail.com wrote: I think he means a program running on the iPhone which allows you to open a terminal over an SSH session to other devices. The instance (I think) you're thinking of is where the SSH *server* runs on the iPhone. Yeah I was talking about a terminal capability that can deal with all the lovely control codes of serial terminals. I thought this could serve as a front-end for something running with curses bindings, not that you need to open up the whole darned iphone to do this stuff. Dave On Mon, Mar 23, 2009 at 2:46 PM, Miguel Mitrofanov miguelim...@yandex.ruwrote: On 23 Mar 2009, at 21:38, David Leimbach wrote: On Mon, Mar 23, 2009 at 11:22 AM, Miguel Mitrofanov miguelim...@yandex.ru wrote: 1) You'll need a terminal application first, and I'm not sure if there is one in AppStore. In fact, I AM sure there isn't. There's SSH terminal programs like Putty based stuff that are in the AppStore. So that sort of thing has been done yes. You sure it can SSH to iPhone itself? Installing Hugs (or GHC) on a desktop PC and connecting to it via ssh is anything but impressive. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- /jve ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: SOC idea ticket: Rendering Engine
Csaba Hruska csaba.hru...@gmail.com wrote: svn checkout *http*://lambdacube.googlecode.com/svn/trunk/lambdacube-read-only I think you mean svn co http://lambdacube.googlecode.com/svn/trunk I didn't do anything yet, except running the sample program. I get to see an ogre head and this: 8 k...@solaris trunk % ./example1 [.,..,car,.svn,packs,materials,models] [.,..,.svn,toonf2.frag,toonf2.vert,Example_CelShading.frag,Example_CelShading.vert,texturemapping.frag,texturemapping.vert,diffuse.frag,diffuse.vert,ambient.frag,ambient.vert] [.,..,.svn,todo,Ogre.material,jaiqua.material,Scene.material,ogrehead.material,Robot.material,RZR-002.material] load: Ogre.material load: jaiqua.material load: Scene.material load: ogrehead.material load: Robot.material load: RZR-002.material [.,..,.svn,cel_shading_diffuse.png,r2skin.jpg,RZR-002.png,cel_shading_specular.png,cel_shading_edge.png,GreenSkin.jpg,spheremap.png,WeirdEye.png,dirt01.jpg,blue_jaiqua.jpg] [.,..,.svn,Cube.mesh.xml,ogrehead.mesh.xml,athene.mesh.xml,ninja.mesh.xml,Suzanne.mesh.xml,RZR-002.mesh.xml,facial.mesh.xml,robot.skeleton.xml,robot.mesh.xml,jaiqua.mesh.xml] [.,..,.svn,scooby_body.mesh.xml,scooby_body.material,ventanas.jpg,chasis.jpg,chasis_a.jpg] load: scooby_body.material creating entity: OgreHead from mesh: ogrehead.mesh.xml parsing XML file [Ogre/Tusks,Ogre/Earring,Ogre/Skin,Ogre/Eyes] compiling material: Ogre/Eyes WeirdEye.png loaded resolution = 256 x 256, 3 bytes per pixel compiling material: Ogre/Skin GreenSkin.jpg loaded resolution = 256 x 256, 3 bytes per pixel compiling material: Ogre/Earring spheremap.png loaded resolution = 256 x 256, 3 bytes per pixel compiling material: Ogre/Tusks dirt01.jpg loaded resolution = 96 x 96, 3 bytes per pixel done creating entity: Robot from mesh: robot2.mesh.xml parsing XML file [Examples/Robot] compiling material: Examples/Robot r2skin.jpg loaded resolution = 512 x 512, 3 bytes per pixel Compiling program: (Just Examples/AmbientShadingVP,Just Examples/AmbientShadingFP) Shader info log for 'Examples/AmbientShadingVP': Shader info log for 'Examples/AmbientShadingFP': Program info log: done creating entity: Car from mesh: scooby_body.mesh.xml parsing XML file [Ac3d/Scooby_Body/Mat001_Tex03,Ac3d/Scooby_Body/Mat001_Tex02,Ac3d/Scooby_Body/Mat001_Tex01] compiling material: Ac3d/Scooby_Body/Mat001_Tex01 chasis.jpg loaded resolution = 512 x 512, 3 bytes per pixel compiling material: Ac3d/Scooby_Body/Mat001_Tex02 ventanas.jpg loaded resolution = 512 x 512, 3 bytes per pixel compiling material: Ac3d/Scooby_Body/Mat001_Tex03 chasis_a.jpg loaded resolution = 128 x 256, 3 bytes per pixel done 1 frames in 13.45548 seconds = 7.431916215549353e-2 FPS zsh: abort ./example1 8 I _think_ example1 is killed by SIGABRT, but I could be wrong, I've never seen this before. Anyway, it's a strange thing. OpenGL vendor string: NVIDIA Corporation OpenGL renderer string: GeForce 7600 GS/PCI/SSE2 OpenGL version string: 2.1.2 NVIDIA 177.82 OpenGL shading language version string: 1.20 NVIDIA via Cg compiler X.Org X Server 1.5.3 Linux solaris 2.6.28-tuxonice-r1 #20 PREEMPT Tue Mar 10 19:07:36 CET 2009 x86_64 AMD Athlon(tm) 64 Processor 3200+ AuthenticAMD GNU/Linux The Glorious Glasgow Haskell Compilation System, version 6.10.1 -- (c) this sig last receiving data processing entity. Inspect headers for copyright history. All rights reserved. Copying, hiring, renting, performance and/or quoting of this signature prohibited. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: SOC idea ticket: Rendering Engine
2009/3/23 Achim Schneider bars...@web.de Csaba Hruska csaba.hru...@gmail.com wrote: svn checkout *http*://lambdacube.googlecode.com/svn/trunk/lambdacube-read-only I think you mean svn co http://lambdacube.googlecode.com/svn/trunk I didn't do anything yet, except running the sample program. I get to see an ogre head and this: 8 k...@solaris trunk % ./example1 [.,..,car,.svn,packs,materials,models] [.,..,.svn,toonf2.frag,toonf2.vert,Example_CelShading.frag,Example_CelShading.vert,texturemapping.frag,texturemapping.vert,diffuse.frag,diffuse.vert,ambient.frag,ambient.vert] [.,..,.svn,todo,Ogre.material,jaiqua.material,Scene.material,ogrehead.material,Robot.material,RZR-002.material] load: Ogre.material load: jaiqua.material load: Scene.material load: ogrehead.material load: Robot.material load: RZR-002.material [.,..,.svn,cel_shading_diffuse.png,r2skin.jpg,RZR-002.png,cel_shading_specular.png,cel_shading_edge.png,GreenSkin.jpg,spheremap.png,WeirdEye.png,dirt01.jpg,blue_jaiqua.jpg] [.,..,.svn,Cube.mesh.xml,ogrehead.mesh.xml,athene.mesh.xml,ninja.mesh.xml,Suzanne.mesh.xml,RZR-002.mesh.xml,facial.mesh.xml,robot.skeleton.xml,robot.mesh.xml,jaiqua.mesh.xml] [.,..,.svn,scooby_body.mesh.xml,scooby_body.material,ventanas.jpg,chasis.jpg,chasis_a.jpg] load: scooby_body.material creating entity: OgreHead from mesh: ogrehead.mesh.xml parsing XML file [Ogre/Tusks,Ogre/Earring,Ogre/Skin,Ogre/Eyes] compiling material: Ogre/Eyes WeirdEye.png loaded resolution = 256 x 256, 3 bytes per pixel compiling material: Ogre/Skin GreenSkin.jpg loaded resolution = 256 x 256, 3 bytes per pixel compiling material: Ogre/Earring spheremap.png loaded resolution = 256 x 256, 3 bytes per pixel compiling material: Ogre/Tusks dirt01.jpg loaded resolution = 96 x 96, 3 bytes per pixel done creating entity: Robot from mesh: robot2.mesh.xml parsing XML file [Examples/Robot] compiling material: Examples/Robot r2skin.jpg loaded resolution = 512 x 512, 3 bytes per pixel Compiling program: (Just Examples/AmbientShadingVP,Just Examples/AmbientShadingFP) Shader info log for 'Examples/AmbientShadingVP': Shader info log for 'Examples/AmbientShadingFP': Program info log: done creating entity: Car from mesh: scooby_body.mesh.xml parsing XML file [Ac3d/Scooby_Body/Mat001_Tex03,Ac3d/Scooby_Body/Mat001_Tex02,Ac3d/Scooby_Body/Mat001_Tex01] compiling material: Ac3d/Scooby_Body/Mat001_Tex01 chasis.jpg loaded resolution = 512 x 512, 3 bytes per pixel compiling material: Ac3d/Scooby_Body/Mat001_Tex02 ventanas.jpg loaded resolution = 512 x 512, 3 bytes per pixel compiling material: Ac3d/Scooby_Body/Mat001_Tex03 chasis_a.jpg loaded resolution = 128 x 256, 3 bytes per pixel done Until this point it is OK. (sorry for the lots of debug info, i'll remove them later) 1 frames in 13.45548 seconds = 7.431916215549353e-2 FPS The FPS calculation is wrong at first frame. I have a geforce 7300 GS and its running at ~670 FPS in 640x480 sized window. The example uses glsl shader. (if you remove robot from the scene then it will be compatible with older graphic cards too) Please press ESC to exit from example program instead of closing the window. The screenshot (http://code.google.com/p/lambdacube/) is taken from example1, you should get same one. zsh: abort ./example1 8 I _think_ example1 is killed by SIGABRT, but I could be wrong, I've never seen this before. Anyway, it's a strange thing. Does the program exit immediatly after the first rendered frame? OpenGL vendor string: NVIDIA Corporation OpenGL renderer string: GeForce 7600 GS/PCI/SSE2 OpenGL version string: 2.1.2 NVIDIA 177.82 OpenGL shading language version string: 1.20 NVIDIA via Cg compiler X.Org X Server 1.5.3 Linux solaris 2.6.28-tuxonice-r1 #20 PREEMPT Tue Mar 10 19:07:36 CET 2009 x86_64 AMD Athlon(tm) 64 Processor 3200+ AuthenticAMD GNU/Linux The Glorious Glasgow Haskell Compilation System, version 6.10.1 I've tested with ghc 6.10.1 on amd sempron 1800+ 32 bit gnu/linux geforce 7300gs. -- (c) this sig last receiving data processing entity. Inspect headers for copyright history. All rights reserved. Copying, hiring, renting, performance and/or quoting of this signature prohibited. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: SOC idea ticket: Rendering Engine
Csaba Hruska csaba.hru...@gmail.com wrote: I _think_ example1 is killed by SIGABRT, but I could be wrong, I've never seen this before. Anyway, it's a strange thing. Does the program exit immediatly after the first rendered frame? Usually yes, sometimes I'm seeing the ogre being rotated before SIGABRT. At first I thought it might be the app getting confused by xmonad resizing it, but switching to twm or kwm didn't help. I'm going to investigate a bit further as soon as I figured out why xmonad doesn't use xinerama(again) after re-compilation. -- (c) this sig last receiving data processing entity. Inspect headers for copyright history. All rights reserved. Copying, hiring, renting, performance and/or quoting of this signature prohibited. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
RE: [Haskell-cafe] Hugs on iPhone
Doesn't Apple Store restrict applications (by policy) so they cannot generate or execute arbitrary code? (That's the reason there's no Flash for iPhone.) That restriction seems like it'd block any interpreter or compiler from being sold, no? -Michael From: haskell-cafe-boun...@haskell.org [mailto:haskell-cafe-boun...@haskell.org] On Behalf Of David Leimbach Sent: Monday, March 23, 2009 12:59 PM To: John Van Enk Cc: haskell-cafe@haskell.org; Miguel Mitrofanov Subject: Re: [Haskell-cafe] Hugs on iPhone On Mon, Mar 23, 2009 at 11:53 AM, John Van Enk vane...@gmail.commailto:vane...@gmail.com wrote: I think he means a program running on the iPhone which allows you to open a terminal over an SSH session to other devices. The instance (I think) you're thinking of is where the SSH *server* runs on the iPhone. Yeah I was talking about a terminal capability that can deal with all the lovely control codes of serial terminals. I thought this could serve as a front-end for something running with curses bindings, not that you need to open up the whole darned iphone to do this stuff. Dave On Mon, Mar 23, 2009 at 2:46 PM, Miguel Mitrofanov miguelim...@yandex.rumailto:miguelim...@yandex.ru wrote: On 23 Mar 2009, at 21:38, David Leimbach wrote: On Mon, Mar 23, 2009 at 11:22 AM, Miguel Mitrofanov miguelim...@yandex.rumailto:miguelim...@yandex.ru wrote: 1) You'll need a terminal application first, and I'm not sure if there is one in AppStore. In fact, I AM sure there isn't. There's SSH terminal programs like Putty based stuff that are in the AppStore. So that sort of thing has been done yes. You sure it can SSH to iPhone itself? Installing Hugs (or GHC) on a desktop PC and connecting to it via ssh is anything but impressive. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.orgmailto:Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- /jve ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: Hugs on iPhone
Miguel Mitrofanov wrote: 3) Personally, I'd love to see ghc on iPhone. It could even persuade me to upgrade. See the GHC-on-ARM page[1] for my work on it last summer, among others'. GHC is tough to port because bootstrapping to new architectures has been broken for a long time, since soon after 6.6.2. My attempts to cross-compile 6.6.1 using the development environment for my Nokia N810 failed, as can be seen in [1]. I attempted several times to build Hugs for it: it would build successfully and then fail to run either on the device, in scratchbox, or natively compiled on x86 because it failed to find the Prelude. I suspect I was doing something wrong in building Hugs, something unrelated to the ARM platform. The good news is that jhc's portable C code works perfectly well -- but of course that is simply running precompiled Haskell apps and not a compiler or interpreter running on the device. Since jhc is not self-hosting (yet?) but instead is built with GHC, that's the best we can do with that approach for now. Braden Shepherdson shepheb [1] http://hackage.haskell.org/trac/ghc/wiki/ArmLinuxGhc ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Hugs on iPhone
http://www.readwriteweb.com/archives/confirmed_apple_and_adobe_coll.php On 23 Mar 2009, at 23:29, Michael Giagnocavo wrote: Doesn’t Apple Store restrict applications (by policy) so they cannot generate or execute arbitrary code? (That’s the reason there’s no Flash for iPhone.) That restriction seems like it’d block any interpreter or compiler from being sold, no? -Michael From: haskell-cafe-boun...@haskell.org [mailto:haskell-cafe-boun...@haskell.org ] On Behalf Of David Leimbach Sent: Monday, March 23, 2009 12:59 PM To: John Van Enk Cc: haskell-cafe@haskell.org; Miguel Mitrofanov Subject: Re: [Haskell-cafe] Hugs on iPhone On Mon, Mar 23, 2009 at 11:53 AM, John Van Enk vane...@gmail.com wrote: I think he means a program running on the iPhone which allows you to open a terminal over an SSH session to other devices. The instance (I think) you're thinking of is where the SSH *server* runs on the iPhone. Yeah I was talking about a terminal capability that can deal with all the lovely control codes of serial terminals. I thought this could serve as a front-end for something running with curses bindings, not that you need to open up the whole darned iphone to do this stuff. Dave On Mon, Mar 23, 2009 at 2:46 PM, Miguel Mitrofanov miguelim...@yandex.ru wrote: On 23 Mar 2009, at 21:38, David Leimbach wrote: On Mon, Mar 23, 2009 at 11:22 AM, Miguel Mitrofanov miguelim...@yandex.ru wrote: 1) You'll need a terminal application first, and I'm not sure if there is one in AppStore. In fact, I AM sure there isn't. There's SSH terminal programs like Putty based stuff that are in the AppStore. So that sort of thing has been done yes. You sure it can SSH to iPhone itself? Installing Hugs (or GHC) on a desktop PC and connecting to it via ssh is anything but impressive. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- /jve ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
RE: [Haskell-cafe] Hugs on iPhone
Guess they ended up making an exception for Flash, finally. Will be interesting to see how they prevent 3rd party stores from running arbitrary Flash games and whatnot. Maybe they'll blacklist any popular sites that are stealing marketshare from the AppStore? -Michael -Original Message- From: Miguel Mitrofanov [mailto:miguelim...@yandex.ru] Sent: Monday, March 23, 2009 2:52 PM To: Michael Giagnocavo Cc: David Leimbach; John Van Enk; haskell-cafe@haskell.org Subject: Re: [Haskell-cafe] Hugs on iPhone http://www.readwriteweb.com/archives/confirmed_apple_and_adobe_coll.php On 23 Mar 2009, at 23:29, Michael Giagnocavo wrote: Doesn't Apple Store restrict applications (by policy) so they cannot generate or execute arbitrary code? (That's the reason there's no Flash for iPhone.) That restriction seems like it'd block any interpreter or compiler from being sold, no? -Michael From: haskell-cafe-boun...@haskell.org [mailto:haskell-cafe-boun...@haskell.org ] On Behalf Of David Leimbach Sent: Monday, March 23, 2009 12:59 PM To: John Van Enk Cc: haskell-cafe@haskell.org; Miguel Mitrofanov Subject: Re: [Haskell-cafe] Hugs on iPhone On Mon, Mar 23, 2009 at 11:53 AM, John Van Enk vane...@gmail.com wrote: I think he means a program running on the iPhone which allows you to open a terminal over an SSH session to other devices. The instance (I think) you're thinking of is where the SSH *server* runs on the iPhone. Yeah I was talking about a terminal capability that can deal with all the lovely control codes of serial terminals. I thought this could serve as a front-end for something running with curses bindings, not that you need to open up the whole darned iphone to do this stuff. Dave On Mon, Mar 23, 2009 at 2:46 PM, Miguel Mitrofanov miguelim...@yandex.ru wrote: On 23 Mar 2009, at 21:38, David Leimbach wrote: On Mon, Mar 23, 2009 at 11:22 AM, Miguel Mitrofanov miguelim...@yandex.ru wrote: 1) You'll need a terminal application first, and I'm not sure if there is one in AppStore. In fact, I AM sure there isn't. There's SSH terminal programs like Putty based stuff that are in the AppStore. So that sort of thing has been done yes. You sure it can SSH to iPhone itself? Installing Hugs (or GHC) on a desktop PC and connecting to it via ssh is anything but impressive. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- /jve ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Function to cast types
On 23 Mar 2009, at 2:20 am, Anonymous Anonymous wrote: Hello, I'm new to haskell, I'm wondering how can you write a function that will do the following: fromIntToString :: Int - String this is a cast function to cast an Int to a String. It cannot be. What could it possibly mean to cast an Int to anything, let alone a string? Haskell isn't C. (Nor is it PL/I.) What to do depends on what you _want_ to do. For example, fromIntToString n = replicate n 'I' will convert 1 to I, 2 to II, 3 to III, and so on. Assuming that you mean that you want a decimal representation of the integer, Read The Fine Manual to find out what 'show' will do. This may well be a homework question, in which case consider: you want to construct an element of a recursively defined data type (list of character). do you *have* a recursively defined data type to start from? If you first distinguish between negative and non-negative integers, do you have a recursively defined data type then? How could you use `div` and `mod` to treat non-negative integers _as if_ they formed a recursively defined data type? What would the base case be? What would the step case be? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: Hugs on iPhone
On Mon, Mar 23, 2009 at 04:41:04PM -0400, Braden Shepherdson wrote: The good news is that jhc's portable C code works perfectly well -- but of course that is simply running precompiled Haskell apps and not a compiler or interpreter running on the device. Since jhc is not self-hosting (yet?) but instead is built with GHC, that's the best we can do with that approach for now. I wondered what would happen if I submitted some jhc generated C for approval, it _almost_ looks like it could have been hand written by someone with an unusual penchant for gotos and their own inscrutable hungarian notation. John -- John Meacham - ⑆repetae.net⑆john⑈ ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] HSTringTemplate and syb-with-class
You don't need to derive ToSElem -- you get the instance for free if you derive Data. Import GenericWithClass to get the instance for Data from syb-with-class, and import GenericStandard for use with Data from the vanilla syb that comes with GHC. Cheers, Sterl. 2009/3/23 Kemps-Benedix Torsten torsten.kemps-bene...@sks-ub.de: Hello all, I’m trying to use the generic capabilities of HSTringTemplate. The documentation claims that the package is able to automatically generate instances of ToSElem if syb-with-class is installed but gives no further details. I installed syb-with-class and then installed HSTringTemplate with additional configure parameter syb-with-class=True. But when I import Text.StringTemplate.GenericWithClass and then try deriving ToSElem or $(derive ToSElem), I just get an error like “Can't make a derived instance of `ToSElem …”. Any suggestions or pointer to further docs? Kind regards Torsten ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Re: Hugs on iPhone
This is solely the reason for my interest in JHC. The agreement doesn't specifically prohibit the use of interpreters (just those than run external code). It also doesn't say anything about machine generated code. The only thing one would have to ensure is that the dependencies of JHC are all compiled in, or statically linked. Shared libs are disallowed in any app. If it has a runtime dependency on gcc (is there such a thing?) Then you would have to statically link it and therefore couldn't sell your application. (gotta love GPL) JHC also helps with another issue: There is some concern about garbage collection schemes, Apple removed their own garbage collector in the iPhone SDK and the docs mention that GC isn't allowed. But there is nothing about that in the Developer Agreement. JHC's region based memory management very closely reflects Apples own convention for using memory pools for all allocation. I speculate that this would less likely to be rejected. . There is also some discussion on both the GHC and JHC mailing list WRT this a month or two ago. I will attempt exactly this scheme later next month, will let you know how it goes. :) On Mon, Mar 23, 2009 at 5:45 PM, John Meacham j...@repetae.net wrote: On Mon, Mar 23, 2009 at 04:41:04PM -0400, Braden Shepherdson wrote: The good news is that jhc's portable C code works perfectly well -- but of course that is simply running precompiled Haskell apps and not a compiler or interpreter running on the device. Since jhc is not self-hosting (yet?) but instead is built with GHC, that's the best we can do with that approach for now. I wondered what would happen if I submitted some jhc generated C for approval, it _almost_ looks like it could have been hand written by someone with an unusual penchant for gotos and their own inscrutable hungarian notation. John -- John Meacham - ⑆repetae.net⑆john⑈ ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- We can't solve problems by using the same kind of thinking we used when we created them. - A. Einstein ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] generalized shuffle
Hi. I have implemented a generalized shuffle function, for the random-shuffle package http://hackage.haskell.org/cgi-bin/hackage-scripts/package/random-shuffle I have not yet commited the change, before that I would like to receive some feedbacks (especially by the original author of the shuffle function, in Cc) The new function is defined in this example: http://hpaste.org/fastcgi/hpaste.fcgi/view?id=2808 Note that it make use of functions not exported by the System.Random.Shuffle module. I have generalized the original shuffle function in two ways: 1) It is now possible to obtain a random sample from a sequence, by doing, as an example: shuffles [1..10] [2, 3, 4, 2, 1] Note that this is equivalent at taking the first 5 elements of the full shuffled sequence, and the performance are pratically the same. 2) It is now possible to pass an infinite r-sequence to the shuffle function, as an example: shuffles [1..10] $ cycle [9, 8 .. 1] The result is an infinite list, with elements cyclically extracted from the r-sequence. When the r-sequence contains random numbers, we get an infinite sequence containing all possible random choices of elements in the original sequence. Why I'm doing this? The reason is that in a project I need to extract random elements from a list (and I need to extract a lot of them), and using normal methods [1] seems to be rather inefficient. Using the `shuffles` function should be much more efficient, since it uses a tree, and this tree is built only once. [1] by normal method I mean: extract a random number, in the range [0, n] (where n is the length of the sequence), and get the element indexed by that number. Indexing for a list if very expensive. And it is not very fast, even using arrays (unless you use non portable unsafeRead). Thanks Manlio Perillo ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Use unsafePerformIO to catch Exception?
On Mon, 23 Mar 2009, Xiao-Yong Jin wrote: Hi, I just feel it is not comfortable to deal with exceptions only within IO monad, so I defined tryArith :: a - Either ArithException a tryArith = unsafePerformIO . try . evaluate and it works quite good as map (tryArith . (div 5)) [2,1,0,5] evaluates to [Right 2,Right 5,Left divide by zero,Right 1] However, I guess unsafePerformIO definitely has a reason for its name. As I read through the document in System.IO.Unsafe, I can't convince myself whether the use of 'tryArith' is indeed safe or unsafe. Try to never use exception handling for catching programming errors! Division by zero is undefined, thus a programming error when it occurs. http://www.haskell.org/haskellwiki/Error http://www.haskell.org/haskellwiki/Exception I'm afraid, a Maybe or Either or Exceptional (see explicit-exception package) return value is the only way to handle exceptional return values properly. Maybe in the larger context of your problem zero denominators can be avoided? Then go this way. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Use unsafePerformIO to catch Exception?
Xiao-Yong Jin wrote: Hi, I just feel it is not comfortable to deal with exceptions only within IO monad, so I defined tryArith :: a - Either ArithException a tryArith = unsafePerformIO . try . evaluate [...] However, I guess unsafePerformIO definitely has a reason for its name. As I read through the document in System.IO.Unsafe, I can't convince myself whether the use of 'tryArith' is indeed safe or unsafe. I know there have been a lot of discussion around unsafePerformIO, but I still can't figure it out by myself. Can someone share some thoughts on this particular use of unsafePerformIO? Is it safe or not? And why? This use of unsafePerformIO is safe, because the original expression you're given is pure[1]. The evaluate lifts the pure value into IO in order to give evaluation-ordering guarantees, though otherwise has no effects. The unsafePerformIO voids those effects, since it makes the value pure again and thus it does not need to grab the RealWorld baton. Note that the correctness argument assumes the value is indeed pure. Some idiot could have passed in (unsafePerformIO launchTheMissiles), which is not safe and the impurity will taint anything that uses it (tryArith, (+1), whatever). But it's the unsafePerformIO in this expression which is bad, not the one in tryArith. tryArith is basically the same as a function I have in my personal utility code: http://community.haskell.org/~wren/wren-extras/Control/Exception/Extras.hs The safely function is somewhat different in that it's a combinator for making *functions* safe, rather than making *expressions* safe as tryArith does. This is necessary because exceptional control flow (by definition) does not honor the boundaries of expressions, but rather attaches semantics to the evaluation of functions. Thus safely is more safe because it ensures you can't force the exception prematurely via sharing: let x = 5`div`0 in ... seq x ... tryArith x -- too late to catch it! oops. Whereas with safely we'd have: let f y = safely (div y) in let x = 5 `f` 0 in ... seq x ... x -- doesn't matter where f or x are used. [1] Ha! If it were _pure_ then it wouldn't be throwing exceptions, now would it :) -- Live well, ~wren ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Learning Haskell
How long did it take you to become proficient in Haskell? By that, I mean - how long until you were just as comfortable with Haskell as you were with your strongest language at that time? -- View this message in context: http://www.nabble.com/Learning-Haskell-tp22673552p22673552.html Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Learning Haskell
I've been messing with Haskell since the Middle of January on evenings and weekends. Just now I'm getting to the point where I can construct nontrivial programs with little help from #haskell. It is by no means my most proficient language, I've been coding C++ and other languages for over 10 years. It is by far my favorite, however, and if I could do it full time I would. On Mon, Mar 23, 2009 at 11:08 PM, Tom.Amundsen tomamund...@gmail.comwrote: How long did it take you to become proficient in Haskell? By that, I mean - how long until you were just as comfortable with Haskell as you were with your strongest language at that time? -- View this message in context: http://www.nabble.com/Learning-Haskell-tp22673552p22673552.html Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- We can't solve problems by using the same kind of thinking we used when we created them. - A. Einstein ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Learning Haskell
I second that! Haskell is a very fun and engaging language (with its accompanying corpus of theorems, and its great community)... My timing is a little bit longer than Rick's... I've been eyeing Haskell for about 8 months, reading books, poking around etc. I've started to feel comfortable enough in the last month to begin a serious(ish) project. For my debut, I'm trying to build a game with HOpenGL. I wouldn't take my 8-month timeline as much of a benchmark, however, since I have not been very deeply involved in studying the language (I have no projects that require day-to-day coding in Haskell). Duane Johnson http://blog.inquirylabs.com/ On Mar 23, 2009, at 9:13 PM, Rick R wrote: I've been messing with Haskell since the Middle of January on evenings and weekends. Just now I'm getting to the point where I can construct nontrivial programs with little help from #haskell. It is by no means my most proficient language, I've been coding C++ and other languages for over 10 years. It is by far my favorite, however, and if I could do it full time I would. On Mon, Mar 23, 2009 at 11:08 PM, Tom.Amundsen tomamund...@gmail.com wrote: How long did it take you to become proficient in Haskell? By that, I mean - how long until you were just as comfortable with Haskell as you were with your strongest language at that time? -- View this message in context: http://www.nabble.com/Learning-Haskell-tp22673552p22673552.html Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- We can't solve problems by using the same kind of thinking we used when we created them. - A. Einstein ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Learning Haskell
Still struggling after almost year (I learn it along with Prolog, Lua, and many other non-C family languages), because I'm not very good at describing solutions. My imperative background is quite strong, but I've been able to switch more easily these days (after taking Functional Programming class at college). -- View this message in context: http://www.nabble.com/Learning-Haskell-tp22673552p22673952.html Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
