RosettaCodeData/Task/Parametric-polymorphism/Clean/parametric-polymorphism-1.clean
Ingy döt Net b83f433714 tasks a-s
2013-04-10 23:57:08 -07:00

5 lines
181 B
Text

::Tree a = Empty | Node a (Tree a) (Tree a)
mapTree :: (a -> b) (Tree a) -> (Tree b)
mapTree f Empty = Empty
mapTree f (Node x l r) = Node (f x) (mapTree f l) (mapTree f r)