sortTreeBy :: (Tree a -> Tree a -> Ordering) -> Tree a -> Tree a
sortTreeBy f (Node x xs) = Node x (sortForestBy f xs)
sortTreeBy :: (Tree a -> Tree a -> Ordering) -> Tree a -> Tree a
sortTreeBy f (Node x xs) = Node x (sortForestBy f xs)
sortTreeBy f (Node x xs) = Node x (sortForestBy f xs)