[Haskell-beginners] function defenition. Do I understand it right?

Ozgur Akgun ozgurakgun at gmail.com
Tue Jul 12 16:05:11 CEST 2011


Hi,

On 12 July 2011 16:15, Brent Yorgey <byorgey at seas.upenn.edu> wrote:

> This message is just because it cannot figure out the type of [] in
> 'putStrLn $ show $ halve []'.  You can write
>
>  putStrLn $ show $ halve ([] :: [Int])
>
> to give it an explicit type.  It's a bit annoying since we happen to
> know that the type of the list makes no difference, but the compiler
> can't figure that out.
>

Actually, the type of the list does make a difference due to different show
instances. Try:

putStrLn $ show $ halve ([] :: [Char])

Cheers,
Ozgur
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