+import Data.Typeable
+
+{- $intro
+Haskell provides indexable /arrays/, which may be thought of as functions
+whose domains are isomorphic to contiguous subsets of the integers.
+Functions restricted in this way can be implemented efficiently;
+in particular, a programmer may reasonably expect rapid access to
+the components. To ensure the possibility of such an implementation,
+arrays are treated as data, not as general functions.
+
+Since most array functions involve the class 'Ix', this module is exported
+from "Data.Array" so that modules need not import both "Data.Array" and
+"Data.Ix".
+-}