Hi,

W dniu 02.03.2014 22:44, Roelof Wobben pisze:

Hello,

I now have to use foldr to find the max value in a list.

So I do this:

import Data.Char

x = foldr max [5,10,2,8.1]
-- Note that comments are preceded by two hyphens
{- or enclosed
   in curly brace/hypens pairs. -}
main = print x

But now I see this error message:

main.hs@7:8-7:13
    No instance for (Show ([[t0]] -> [t0])) arising from a use of `print' Possible fix: add an instance declaration for (Show ([[t0]] -> [t0])) In the expression: print x In an equation for `main': main = print x

  Please look at foldr type and documentation. There is one argument missing in your code.

Regards,
Emanuel

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