Updates for 0.7

Author: paf31

examples/Collatz.purs

@@ -1,5 +1,7 @@
 module Main where
 
+import Prelude
+
 import Data.Tuple
 import Data.Maybe
 import Data.Array
@@ -8,7 +10,7 @@ import Data.Int
 
 import Console
 
-collatz :: Int -> [Int]
+collatz :: Int -> Array Int
 collatz = unfoldr step 
   where
   step n | n == one = Nothing

src/Data/Unfoldable.purs

@@ -6,6 +6,8 @@
 
 module Data.Unfoldable where
 
+import Prelude
+
 import Data.Maybe
 import Data.Tuple
 import Data.Array.ST
@@ -23,7 +25,7 @@ import Control.Monad.ST
 class Unfoldable t where
   unfoldr :: forall a b. (b -> Maybe (Tuple a b)) -> b -> t a
 
-instance unfoldableArray :: Unfoldable [] where
+instance unfoldableArray :: Unfoldable Array where
   unfoldr f b = runPure (runSTArray (do
     arr  <- emptySTArray
     seed <- newSTRef b