"sleep" in Haskell

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Re: [Haskell-beginners] "sleep" in...

Michael Mossey

14 Oct 2009 14 Oct '09

4:50 p.m.

I can't find a "sleep" function in Haskell. This relates to my wish to use PortMidi and control the timing of actions. Maybe there is another way to do this sort of thing in Haskell. Can anyone help, either with PortMidi or just a general explanation of how IO operations could be placed at certain points in time? Thanks, Mike

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Joe Fredette

14 Oct 14 Oct

4:51 p.m.

As I recall, System.Thread (or something similar) provides "threadSleep". A quick hoogle ought to find it. hoogle -> haskell.org/hoogle On Oct 14, 2009, at 4:50 PM, Michael Mossey wrote:

...

I can't find a "sleep" function in Haskell. This relates to my wish to use PortMidi and control the timing of actions. Maybe there is another way to do this sort of thing in Haskell. Can anyone help, either with PortMidi or just a general explanation of how IO operations could be placed at certain points in time?

Thanks, Mike _______________________________________________ Beginners mailing list Beginners@haskell.org http://www.haskell.org/mailman/listinfo/beginners

Michael Mossey

4:54 p.m.

Hi Joe, My program does not need to be threaded, so initially I ignored System.Thread, but perhaps either (1) This particular function can be used in a single-thread process or (2) I need to learn how to use threads if I want to place IO operations in time. ? Joe Fredette wrote:

...

As I recall, System.Thread (or something similar) provides "threadSleep". A quick hoogle ought to find it.

hoogle -> haskell.org/hoogle

On Oct 14, 2009, at 4:50 PM, Michael Mossey wrote:

...
I can't find a "sleep" function in Haskell. This relates to my wish to use PortMidi and control the timing of actions. Maybe there is another way to do this sort of thing in Haskell. Can anyone help, either with PortMidi or just a general explanation of how IO operations could be placed at certain points in time?

Thanks, Mike _______________________________________________ Beginners mailing list Beginners@haskell.org http://www.haskell.org/mailman/listinfo/beginners

Joe Fredette

4:58 p.m.

Your program may not be multithreaded, but it is threaded. :) so threadSleep <ms> will still work, it'll just pause the thread it's executed in, namely the main thread, which is the one you want. So I guess the answer to your first question is yes, it can be used. And 2, no you don't need to learn to use threads, beyond the very basic calling of threadSleep. On Oct 14, 2009, at 4:54 PM, Michael Mossey wrote:

...

Hi Joe,

My program does not need to be threaded, so initially I ignored System.Thread, but perhaps either

(1) This particular function can be used in a single-thread process

or

(2) I need to learn how to use threads if I want to place IO operations in time.

?

Joe Fredette wrote:

...
As I recall, System.Thread (or something similar) provides "threadSleep". A quick hoogle ought to find it. hoogle -> haskell.org/hoogle On Oct 14, 2009, at 4:50 PM, Michael Mossey wrote:

...
I can't find a "sleep" function in Haskell. This relates to my wish to use PortMidi and control the timing of actions. Maybe there is another way to do this sort of thing in Haskell. Can anyone help, either with PortMidi or just a general explanation of how IO operations could be placed at certain points in time?

Thanks, Mike _______________________________________________ Beginners mailing list Beginners@haskell.org http://www.haskell.org/mailman/listinfo/beginners

Beginners mailing list Beginners@haskell.org http://www.haskell.org/mailman/listinfo/beginners

Michael Mossey

7:14 p.m.

Hmm, I can't find anything like this. Do you have any other ideas? Joe Fredette wrote:

...

As I recall, System.Thread (or something similar) provides "threadSleep". A quick hoogle ought to find it.

hoogle -> haskell.org/hoogle

On Oct 14, 2009, at 4:50 PM, Michael Mossey wrote:

...
I can't find a "sleep" function in Haskell. This relates to my wish to use PortMidi and control the timing of actions. Maybe there is another way to do this sort of thing in Haskell. Can anyone help, either with PortMidi or just a general explanation of how IO operations could be placed at certain points in time?

Thanks, Mike _______________________________________________ Beginners mailing list Beginners@haskell.org http://www.haskell.org/mailman/listinfo/beginners

Brandon S. Allbery KF8NH

7:16 p.m.

On Oct 14, 2009, at 19:14 , Michael Mossey wrote:

...

Hmm, I can't find anything like this. Do you have any other ideas?

It's actually in Control.Concurrent. -- brandon s. allbery [solaris,freebsd,perl,pugs,haskell] allbery@kf8nh.com system administrator [openafs,heimdal,too many hats] allbery@ece.cmu.edu electrical and computer engineering, carnegie mellon university KF8NH

aditya siram

7:20 p.m.

Look here: http://haskell.org/ghc/docs/latest/html/libraries/base/Control-Concurrent.ht... Here is a sample function that delays for 3 seconds and then dies: main :: IO () main = do threadDelay 30000 return () -deech On Wed, Oct 14, 2009 at 6:16 PM, Brandon S. Allbery KF8NH < allbery@ece.cmu.edu> wrote:

...

On Oct 14, 2009, at 19:14 , Michael Mossey wrote:

...
Hmm, I can't find anything like this. Do you have any other ideas?

It's actually in Control.Concurrent.

-- brandon s. allbery [solaris,freebsd,perl,pugs,haskell] allbery@kf8nh.com system administrator [openafs,heimdal,too many hats] allbery@ece.cmu.edu electrical and computer engineering, carnegie mellon university KF8NH

_______________________________________________ Beginners mailing list Beginners@haskell.org http://www.haskell.org/mailman/listinfo/beginners

Magnus Therning

15 Oct 15 Oct

3:49 a.m.

On Thu, Oct 15, 2009 at 12:20 AM, aditya siram wrote:

...

Look here: http://haskell.org/ghc/docs/latest/html/libraries/base/Control-Concurrent.ht...

Here is a sample function that delays for 3 seconds and then dies: main :: IO () main = do threadDelay 30000 return ()

Sorry, but I can't help myself... the above is equivalent to main :: IO () main = threadDelay 3000 /M -- Magnus Therning (OpenPGP: 0xAB4DFBA4) magnus＠therning．org Jabber: magnus＠therning．org http://therning.org/magnus identi.ca|twitter: magthe

Lorcan McDonald

4:03 a.m.

Hi, I was looking at something similar recently and I found the examples in the hmidi package to be useful for this. cabal install hmidi and the examples are in ~/.cabal/packages/hackage.haskell.org/hmidi/0.1/hmidi-0.1.tar.gz (on Mac OS X) On Thu, Oct 15, 2009 at 8:49 AM, Magnus Therning wrote:

...

On Thu, Oct 15, 2009 at 12:20 AM, aditya siram wrote:

...
Look here: http://haskell.org/ghc/docs/latest/html/libraries/base/Control-Concurrent.ht...

Here is a sample function that delays for 3 seconds and then dies: main :: IO () main = do threadDelay 30000 return ()

Sorry, but I can't help myself... the above is equivalent to

main :: IO () main = threadDelay 3000

/M

-- Magnus Therning (OpenPGP: 0xAB4DFBA4) magnus＠therning．org Jabber: magnus＠therning．org http://therning.org/magnus identi.ca|twitter: magthe _______________________________________________ Beginners mailing list Beginners@haskell.org http://www.haskell.org/mailman/listinfo/beginners

Michael Mossey

4:30 a.m.

That's very helpful info. I'm glad hmidi comes with an example. I can't find one for PortMidi, but maybe I'll figure out some basics with hmidi. Lorcan McDonald wrote:

...

Hi,

I was looking at something similar recently and I found the examples in the hmidi package to be useful for this.

cabal install hmidi and the examples are in ~/.cabal/packages/hackage.haskell.org/hmidi/0.1/hmidi-0.1.tar.gz (on Mac OS X)

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aditya siram
Brandon S. Allbery KF8NH
Joe Fredette
Lorcan McDonald
Magnus Therning
Michael Mossey

"sleep" in Haskell

Michael Mossey

Joe Fredette

Michael Mossey

Joe Fredette

Michael Mossey

Brandon S. Allbery KF8NH

aditya siram

Magnus Therning

Lorcan McDonald

Michael Mossey

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