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Today's Topics:
1. Re: Problem to compile an example of Data Parallel Haskell
(Brent Yorgey)
2. Re: using quickcheck for blackbox testing for 3rd party
apps. (Brent Yorgey)
3. Re: using quickcheck for blackbox testing for 3rd party
apps. (Daniel Fischer)
4. new locale? (Robert Wills)
5. "sleep" in Haskell (Michael Mossey)
6. Re: "sleep" in Haskell (Joe Fredette)
7. Re: "sleep" in Haskell (Michael Mossey)
8. Re: "sleep" in Haskell (Michael Mossey)
9. Re: "sleep" in Haskell (Joe Fredette)
10. Re: "sleep" in Haskell (Joe Fredette)
----------------------------------------------------------------------
Message: 1
Date: Tue, 13 Oct 2009 11:51:39 -0400
From: Brent Yorgey <byor...@seas.upenn.edu>
Subject: Re: [Haskell-beginners] Problem to compile an example of Data
Parallel Haskell
To: beginners@haskell.org
Message-ID: <20091013155139.ga2...@seas.upenn.edu>
Content-Type: text/plain; charset=us-ascii
On Mon, Oct 12, 2009 at 02:26:28PM +0200, Edgar GOMES DE ARAUJO wrote:
> Hi,
>
> I have tried to compile an example of DPH (Data prallel Haskell) but I am
> not getting any success.
> The target is the concmop.hs
> (http://darcs.haskell.org/ghc-6.10/packages/dph/examples/concomp/) for
> calculate connected components in a graph. I am using GHC 6.10.4 compiled
> with extras libs (which also includes DPH 0.3.0).
> I've got this error. Seems that GHC can't find these functions/types.
>
> ---------------------------------------------------------------------------------------------------------------------
> ed...@edgar-ubuntu:~/Desktop/dph$ ghc --make -fdph-par -XTypeOperators
> ./concomp.hs
> [1 of 4] Compiling Graph ( Graph.hs, Graph.o )
>
> Graph.hs:11:45: Not in scope: type constructor or class `:*:'
>
> Graph.hs:23:6: Not in scope: `hPutU'
>
> Graph.hs:33:15: Not in scope: `hGetU'
> ---------------------------------------------------------------------------------------------------------------------
Perhaps that file is just missing an import? IIRC these things are
from Data.Array.Vector, from the uvector package.
-Brent
------------------------------
Message: 2
Date: Tue, 13 Oct 2009 12:04:52 -0400
From: Brent Yorgey <byor...@seas.upenn.edu>
Subject: Re: [Haskell-beginners] using quickcheck for blackbox testing
for 3rd party apps.
To: beginners@haskell.org
Message-ID: <20091013160452.gb2...@seas.upenn.edu>
Content-Type: text/plain; charset=us-ascii
On Mon, Oct 12, 2009 at 11:51:49AM +0530, Srikanth K wrote:
>
> However, being a newbie, I am not able to understand how I can extract the
> "Response" part from the IO Response.
>
> I want something as follows
> prop_App state_x command_y = (abstract_App state_x command_y ) == (real_App
> state_x command_y)
>
>
> The issue here is that since the reall_App would return a "IO Response" and
> not "Response" I cannot really compare the abstract_App with the real_App.
>
> Any thought on how I can extract the value from the "IO Response" so that I
> can compare the the two implementations for equvivalence.
Hi Srikanth,
The short answer is: you can't extract a Response from an IO Response.
Once something is infected with IO, there's no cure!* However, you can
compare the responses if you make the result of prop_App an IO action
itself:
prop_App :: State -> Command -> IO Bool
prop_App state_x command_y = do
realResponse <- real_App state_x command_y
return $ abstract_App state_x command_y == realResponse
Off the top of my head I'm not sure of the proper way to run such
monadic tests with QuickCheck, but it can definitely be done.
-Brent
* Some smart-alecks might pipe up with something about unsafePerformIO
here. But that's not a cure, it's more like performing an emergency
tracheotomy with a ballpoint pen.
------------------------------
Message: 3
Date: Tue, 13 Oct 2009 19:34:36 +0200
From: Daniel Fischer <daniel.is.fisc...@web.de>
Subject: Re: [Haskell-beginners] using quickcheck for blackbox testing
for 3rd party apps.
To: beginners@haskell.org, haskell-c...@haskell.org
Message-ID: <200910131934.36808.daniel.is.fisc...@web.de>
Content-Type: text/plain; charset="iso-8859-1"
Am Dienstag 13 Oktober 2009 18:04:52 schrieb Brent Yorgey:
> Brent
>
> * Some smart-alecks might pipe up with something about unsafePerformIO
> here. But that's not a cure, it's more like performing an emergency
> tracheotomy with a ballpoint pen.
Quote of the month!
------------------------------
Message: 4
Date: Wed, 14 Oct 2009 05:44:34 +0100
From: Robert Wills <wrwi...@gmail.com>
Subject: [Haskell-beginners] new locale?
To: beginners@haskell.org
Message-ID: <4ad55732.6010...@gmail.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Hello,
http://hackage.haskell.org/package/old-locale-1.0.0.1
says "This package provides the old locale library. For new code, the
new locale library is recommended."
Does anyone know where I would find the new library?
Thanks,
Rob
------------------------------
Message: 5
Date: Wed, 14 Oct 2009 13:50:11 -0700
From: Michael Mossey <m...@alumni.caltech.edu>
Subject: [Haskell-beginners] "sleep" in Haskell
To: beginners <beginners@haskell.org>
Message-ID: <4ad63983.8000...@alumni.caltech.edu>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
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
------------------------------
Message: 6
Date: Wed, 14 Oct 2009 16:51:50 -0400
From: Joe Fredette <jfred...@gmail.com>
Subject: Re: [Haskell-beginners] "sleep" in Haskell
To: Michael Mossey <m...@alumni.caltech.edu>
Cc: beginners <beginners@haskell.org>
Message-ID: <2815f39f-aeb3-49d6-9337-b44690da0...@gmail.com>
Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes
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
------------------------------
Message: 7
Date: Wed, 14 Oct 2009 13:54:43 -0700
From: Michael Mossey <m...@alumni.caltech.edu>
Subject: Re: [Haskell-beginners] "sleep" in Haskell
To: beginners <beginners@haskell.org>
Message-ID: <4ad63a93.2040...@alumni.caltech.edu>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
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
>
------------------------------
Message: 8
Date: Wed, 14 Oct 2009 13:58:00 -0700
From: Michael Mossey <m...@alumni.caltech.edu>
Subject: Re: [Haskell-beginners] "sleep" in Haskell
To: beginners <beginners@haskell.org>
Message-ID: <4ad63b58.5060...@alumni.caltech.edu>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Hi Philippa,
I think you have the right idea, and I want to try that too, but right now
I'm using a kind of scattershot approach to try and learn everything I can,
both about MIDI and Haskell in general. Since nothing is currently working,
getting anything to work would be a learning experience.
Thanks,
Mike
Philippa Cowderoy wrote:
> 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?
>>
>
> Y'know, I can't think of a single language where I'd consider using the
> sleep function to time MIDI output. It's normally done with buffered
> I/O. I don't know PortMidi, though.
>
------------------------------
Message: 9
Date: Wed, 14 Oct 2009 16:58:55 -0400
From: Joe Fredette <jfred...@gmail.com>
Subject: Re: [Haskell-beginners] "sleep" in Haskell
To: Michael Mossey <m...@alumni.caltech.edu>
Cc: beginners <beginners@haskell.org>
Message-ID: <c944d186-01bc-4e15-a5e9-fa6392a91...@gmail.com>
Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes
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
------------------------------
Message: 10
Date: Wed, 14 Oct 2009 17:00:07 -0400
From: Joe Fredette <jfred...@gmail.com>
Subject: Re: [Haskell-beginners] "sleep" in Haskell
To: Michael Mossey <m...@alumni.caltech.edu>
Cc: beginners <beginners@haskell.org>
Message-ID: <650292fe-20bc-40c1-b6c1-0c54a7295...@gmail.com>
Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes
>> Second reply to the same email, completely off topic.
MIDI + Haskell = Computer Music, I'm already excited to see results,
make sure you put stuff on hackage!
/Joe
On Oct 14, 2009, at 4:58 PM, Michael Mossey wrote:
> Hi Philippa,
>
> I think you have the right idea, and I want to try that too, but
> right now I'm using a kind of scattershot approach to try and learn
> everything I can, both about MIDI and Haskell in general. Since
> nothing is currently working, getting anything to work would be a
> learning experience.
>
> Thanks,
> Mike
>
> Philippa Cowderoy wrote:
>> 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?
>>>
>> Y'know, I can't think of a single language where I'd consider using
>> the sleep function to time MIDI output. It's normally done with
>> buffered I/O. I don't know PortMidi, though.
> _______________________________________________
> Beginners mailing list
> Beginners@haskell.org
> http://www.haskell.org/mailman/listinfo/beginners
------------------------------
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