[Haskell-cafe] Monad for binary tree data structure

[Александр]

Hello,

I built binary tree with:


data Tree a = Empty  
              | Node a (Tree a) (Tree a) 
              deriving (Eq, Ord, Read, Show)

How can i make Monad type class instance for this tree? And can i make it on not?

i try:


instance Monad Tree where
    return x = Node x Empty Empty 
    Empty >>= f = Empty
    (Node x Empty Empty) >>= f = f x 

But i can't make (>>=) for Node x left right. 
Thank you. 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.haskell.org/pipermail/haskell-cafe/attachments/20110723/6bed6eec/attachment.htm>