Hi!
When I was trying to sleep last night I though I could implement Search Trees
in Haskell.
And not only that, I would try to implement them as monads.
The problem is that search trees require context Ord a.
What I want is something like the following:
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module SearchTree where
data Ord a => SearchTree a = Empty
| T a (SearchTree a) (SearchTree a)
instance Monad SearchTree where
(T a l r) >>= f = (f a) ++ (l >>= f) ++ (r >>= f)
Empty >>= f = Empty
return a = T a Empty Empty
instance MonadZero SearchTree where
zero = Empty
instance MonadPlus SearchTree where
Empty ++ x = x
x ++ Empty = x
(T a l r) ++ y@(T b _ _) | b > a = T a l (r ++ y)
| True = T a (l ++ y) r
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Since Ord a is required for SearchTree a, I would want this to work.
Does anyone know if this is possible to do in Haskell?
Please reply by mail directly to me as well.
n.
-----[ norpan ]---------[ [EMAIL PROTECTED] ]--------[ martin norb{ck ]-----
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