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Today's Topics:
1. Re: [Haskell-cafe] What is an "expected type" ... (michael rice)
2. Re: High precision doubles (Felipe Lessa)
3. Re: Rigid type variables match error (Felipe Lessa)
4. Re: High precision doubles (Matthew Eastman)
5. GHC compiling for different platforms (Bernhard Lehnert)
6. Re: GHC compiling for different platforms (Magnus Therning)
----------------------------------------------------------------------
Message: 1
Date: Sun, 28 Jun 2009 09:39:37 -0700 (PDT)
From: michael rice <[email protected]>
Subject: [Haskell-beginners] Re: [Haskell-cafe] What is an "expected
type" ...
To: "Brandon S. Allbery KF8NH" <[email protected]>
Cc: [email protected], Haskell Cafe mailing list
<[email protected]>
Message-ID: <[email protected]>
Content-Type: text/plain; charset="iso-8859-1"
How else? ;-)
Thanks,
Michael
--- On Sun, 6/28/09, Brandon S. Allbery KF8NH <[email protected]> wrote:
From: Brandon S. Allbery KF8NH <[email protected]>
Subject: Re: [Haskell-cafe] What is an "expected type" ...
To: "michael rice" <[email protected]>
Cc: "Brandon S. Allbery KF8NH" <[email protected]>, "Joe Fredette"
<[email protected]>, [email protected], "Haskell Cafe mailing list"
<[email protected]>
Date: Sunday, June 28, 2009, 12:06 PM
On Jun 28, 2009, at 12:02 , michael rice wrote:dec2bin :: Integer -> [Integer]
dec2bin n = dec2bin' n []
where dec2bin' n acc
| n == 0 = acc
| otherwise = let r = rem n 2
m = div (n - r) 2
in dec2bin' m (r : acc)
is there any way to assign a type signature to the helper function?
Same way you do for a top level binding:
dec2bin :: Integer -> [Integer]
dec2bin n = dec2bin' n []
where dec2bin' :: Integer -> [Integer] -> [Integer]
dec2bin' n acc
| n == 0 = acc
| otherwise = let r = rem n 2
m = div (n - r) 2
in dec2bin' m (r : acc)
-- brandon s. allbery [solaris,freebsd,perl,pugs,haskell]
[email protected] administrator [openafs,heimdal,too many hats]
[email protected] and computer engineering, carnegie mellon
university KF8NH
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Message: 2
Date: Sun, 28 Jun 2009 23:55:54 -0300
From: Felipe Lessa <[email protected]>
Subject: Re: [Haskell-beginners] High precision doubles
To: [email protected]
Message-ID: <[email protected]>
Content-Type: text/plain; charset=us-ascii
On Sun, Jun 28, 2009 at 10:34:51PM -0400, Matthew Eastman wrote:
> Just for fun, one of the mazes it made:
>
> ___ ___ ___ ___ ___
> ___/ \___/ \___/ \___/ \___/ \___
> / \ \ / / / \ \
> \ \___/ ___/ ___/ / \ /
> / \___/ ___ \ \___/ \ / \
> \ / \___/ \ / \ / \___ \ /
> / / ___/ \___/ ___ \___/ \
> \___/ / \___ \___/ \___ \ /
> / \ / ___ ___/ \___/ \
> \___ \___/ \ \ / ___/
> / ___ \___/ \___/ \___/ \___ \
> \___/ \___/ \___/ \___/ \___/ \___/
This is beautiful! Do you plan releasing something to Hackage?
--
Felipe.
------------------------------
Message: 3
Date: Mon, 29 Jun 2009 00:09:23 -0300
From: Felipe Lessa <[email protected]>
Subject: Re: [Haskell-beginners] Rigid type variables match error
To: [email protected]
Message-ID: <[email protected]>
Content-Type: text/plain; charset=us-ascii
On Sat, Jun 27, 2009 at 10:18:02AM +0930, Darryn wrote:
> class A a where
> a1 :: a
> a2 :: a -> a
> a3 :: (B b) => b -> a
It is clear here that 'b' is different from 'a' on 'a3's
definition, right? Now let's rename 'b' to 'c' on your instance:
> -- note that 'a = Ainst c' here.
> instance (B c) => A (Ainst c) where
> a1 :: Ainst c
> a1 = I
> a2 :: Ainst c -> Ainst c
> a2 = J
> a3 :: (B b) => b -> Ainst c
> a3 = ...
Oops! We have 'K :: (B b) => b -> Ainst b', but 'a3 :: (B b) =>
b -> Ainst c' is more general than that.
Hope that helps,
--
Felipe.
------------------------------
Message: 4
Date: Mon, 29 Jun 2009 11:03:25 -0400
From: Matthew Eastman <[email protected]>
Subject: Re: [Haskell-beginners] High precision doubles
To: [email protected]
Message-ID: <[email protected]>
Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes
Sure, I can put it on Hackage. I'll have to figure out how to use
Cabal, and tidy up the code, but I'll upload it sooner or later.
On 28-Jun-09, at 10:55 PM, Felipe Lessa wrote:
> On Sun, Jun 28, 2009 at 10:34:51PM -0400, Matthew Eastman wrote:
>> Just for fun, one of the mazes it made:
>>
>> ___ ___ ___ ___ ___
>> ___/ \___/ \___/ \___/ \___/ \___
>> / \ \ / / / \ \
>> \ \___/ ___/ ___/ / \ /
>> / \___/ ___ \ \___/ \ / \
>> \ / \___/ \ / \ / \___ \ /
>> / / ___/ \___/ ___ \___/ \
>> \___/ / \___ \___/ \___ \ /
>> / \ / ___ ___/ \___/ \
>> \___ \___/ \ \ / ___/
>> / ___ \___/ \___/ \___/ \___ \
>> \___/ \___/ \___/ \___/ \___/ \___/
>
> This is beautiful! Do you plan releasing something to Hackage?
>
> --
> Felipe.
> _______________________________________________
> Beginners mailing list
> [email protected]
> http://www.haskell.org/mailman/listinfo/beginners
------------------------------
Message: 5
Date: Mon, 29 Jun 2009 22:53:22 +0200
From: Bernhard Lehnert <[email protected]>
Subject: [Haskell-beginners] GHC compiling for different platforms
To: [email protected]
Message-ID: <1246308802.12903.16.ca...@sol>
Content-Type: text/plain
Hi folks!
When I compile a program under windows - will the .exe run under any
windows? Do I have to distribute only the .exe or more files?
When I compile a program under a 64bit-Linux on an AMD-CPU, will the
executable run under 32bit and/or Intel-CPU as well? Are there any, say,
compiler flags, to improve portability?
Thanks,
Bernhard
------------------------------
Message: 6
Date: Mon, 29 Jun 2009 23:05:36 +0100
From: Magnus Therning <[email protected]>
Subject: Re: [Haskell-beginners] GHC compiling for different platforms
To: [email protected]
Message-ID: <[email protected]>
Content-Type: text/plain; charset="utf-8"
Bernhard Lehnert wrote:
> Hi folks!
>
> When I compile a program under windows - will the .exe run under any
> windows? Do I have to distribute only the .exe or more files?
In my experience, yes. But I have really only taken .exe's compiled on XP to
run on Vista and w2k3.
> When I compile a program under a 64bit-Linux on an AMD-CPU, will the
> executable run under 32bit and/or Intel-CPU as well? Are there any, say,
> compiler flags, to improve portability?
I don't think you'll have any success in running a 64-bit executable on a 32
bit system.
However, I think most 64-bit systems are able to run 32-bit executables. I
suspect GHC, with its static linking is a rather easier platform than C/C++
with its typically large set of shared objects.
/M
--
Magnus Therning (OpenPGP: 0xAB4DFBA4)
magnusï¼ therningï¼org Jabber: magnusï¼ therningï¼org
http://therning.org/magnus identi.ca|twitter: magthe
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