[Haskell-cafe] Re: [Haskell] Re: sizeFM type
ketil+haskell at ii.uib.no
Tue Apr 27 10:44:40 EDT 2004
[Moved to -cafe at SPJ's request]
"Serge D. Mechveliani" <mechvel at botik.ru> writes:
> On Mon, Apr 26, 2004 at 10:09:18PM +0200, Ketil Malde wrote:
>> "Serge D. Mechveliani" <mechvel at botik.ru> writes:
>>> length :: [a] -> Integer
>>> smallLength :: [a] -> Int
>> Hmm...isn't it possible to use a class here? Perhaps even Num?
> I think, for many functions, like length, it is most natural to
> return Integer only.
Well, perhaps Integral is a better choice. I was perhaps thinking of
average xs = sum xs / length xs
I'd rather have a polymorphic "length", than different versions for
each possible return type. One problem could be that with
average xs = sum xs / fromIntegral (length xs)
the return type of length becomes ambigous?
If I haven't seen further, it is by standing in the footprints of giants
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