[Haskell-beginners] A "show" error

[Ozgur Akgun]

Hi again,

What interpreter do you use? With ghci, I don't get any errors.

*Main> f (Branch 12 (Branch 15 Empty Empty) (Branch 28 Empty Empty))
(12,15,Empty,Empty,28,Empty,Empty)

On 11 March 2012 19:10, bahadýr altan <doaltan at yahoo.co.uk> wrote:

> Hi,
> I'm trying to process on a tree with this function :
>
> f (Branch x (Branch y y1 y2) (Branch z z1 z2)) = (x,y,y1,y2,z,z1,z2)
>
> and my tree declaration is this :
>
> data Tree = Empty | Branch Integer Tree Tree deriving (Show)
>
> And I'm getting this error :
>
> Main> f (Branch 12 (Branch 15 Empty Empty) (Branch 28 Empty Empty))
> ERROR - Cannot find "show" function for:
> *** Expression : f (Branch 12 (Branch 15 Empty Empty) (Branch 28 Empty
> Empty))
> *** Of type    : (Integer,Integer,Tree,Tree,Integer,Tree,Tree)
>
> I'll be happy if you help me to get rid of this error..
>

-- 
Ozgur Akgun
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