And for those functions there are often generic counterparts defined in the List module eg genericLength that take Integral types. On 23 June 2010 15:52, Ertugrul Soeylemez wrote:

Hello Lyndon,

it seems to me that Integer /is/ the default. Probably you're unifying with some Int, for example when using functions like 'take' or 'length':

length :: [a] -> Int take :: Int -> [a] -> [a]

Greets, Ertugrul

Lyndon Maydwell wrote:

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Hi beginners.

Is there a way to get the prelude functions to use Integer by default rather than Int?

I often have issues with Ints silently overflowing silently, but don't often have speed issues.

Somehow I don't think that this is possible, but... Maybe?

-- nightmare = unsafePerformIO (getWrongWife >>= sex) http://blog.ertes.de/

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Ah, that's probably it. I suppose there's no way of making the overflow throw an exception without sacrificing significant performance.

On Wednesday 23 June 2010 18:08:18, Colin Paul Adams wrote:

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"Ertugrul" == Ertugrul Soeylemez writes:

Ertugrul> -- nightmare = unsafePerformIO (getWrongWife >>= sex)

I can't work out the signature for nightmare (in your signature).

:-)

My guess: getWrongWife :: IO Partner sex :: Partner -> IO Offspring

On Wed, Jun 23, 2010 at 05:20:16PM +0100, Colin Paul Adams wrote:

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"Daniel" == Daniel Fischer writes:

Daniel> On Wednesday 23 June 2010 18:08:18, Colin Paul Adams wrote: >> >>>>> "Ertugrul" == Ertugrul Soeylemez writes: >> Ertugrul> -- nightmare = unsafePerformIO (getWrongWife >>= sex) >> >> I can't work out the signature for nightmare (in your signature). >> >> :-)

Daniel> My guess:

Daniel> getWrongWife :: IO Partner sex :: Partner -> IO Offspring

So

nightmare :: Offspring ?

I guess it would be better to have sex :: Partner -> IO (Maybe Offspring) or, if you are lucky/unlucky: sex :: Partner -> IO [Offspring] -- Felipe.

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"Patrick" == Patrick LeBoutillier writes:

>>> >>> So >>> >>> nightmare :: Offspring ? >> If you make Patrick> sex :: Partner -> IO [STD] Patrick> then perhaps Patrick> nightmare :: [STD] Patrick> becomes more universal... What's an STD? -- Colin Adams Preston Lancashire () ascii ribbon campaign - against html e-mail /\ www.asciiribbon.org - against proprietary attachments

Daniel Fischer wrote:

On Wednesday 23 June 2010 19:01:21, Colin Paul Adams wrote:

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> "Patrick" == Patrick LeBoutillier writes: >>> So >>> >>> nightmare :: Offspring ?

If you make

Patrick> sex :: Partner -> IO [STD]

Patrick> then perhaps

Patrick> nightmare :: [STD]

Patrick> becomes more universal...

What's an STD?

Sexually transmitted disease

Anyway, don't perform IO unsafely. You might regret it. Sex is another form of -- well -- input and output. Here are the types: getWrongWife :: IO BadWife sex :: F___able a => a -> IO (MVar Offspring, Set Disease) Of course you don't get offspring, if you don't "take" it. Greets, Ertugrul -- nightmare = unsafePerformIO (getWrongWife >>= sex) http://blog.ertes.de/

On Wed, 2010-06-23 at 11:51 -0300, Felipe Lessa wrote:

On Wed, Jun 23, 2010 at 09:38:24PM +0800, Lyndon Maydwell wrote:

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Is there a way to get the prelude functions to use Integer by default rather than Int?

In general, I think it is cleaner to use explicit type signatures instead of defaulting. Running GHC with -Wall will warn you whenever you default to something.

Cheers,

-- Felipe.

Also it helps a lot tracking type errors (and other errors are nearly non-existing in Haskell ;) ). Regards