diff --git a/Data/Array/Base.hs b/Data/Array/Base.hs
--- a/Data/Array/Base.hs
+++ b/Data/Array/Base.hs
@@ -1,4 +1,4 @@
-{-# OPTIONS_GHC -XNoBangPatterns -fno-warn-unused-imports #-}
+{-# OPTIONS_GHC -XBangPatterns -fno-warn-unused-imports #-}
 {-# OPTIONS_HADDOCK hide #-}
 -- XXX With a GHC 6.9 we get a spurious
 -- Data/Array/Base.hs:26:0:
@@ -295,7 +295,7 @@
 {-# INLINE (!) #-}
 -- | Returns the element of an immutable array at the specified index.
 (!) :: (IArray a e, Ix i) => a i e -> i -> e
-arr ! i = case bounds arr of
+(!) arr i = case bounds arr of
               (l,u) -> unsafeAt arr $ safeIndex (l,u) (numElements arr) i
 
 {-# INLINE indices #-}
diff --git a/Data/Array/IO.hs b/Data/Array/IO.hs
--- a/Data/Array/IO.hs
+++ b/Data/Array/IO.hs
@@ -74,8 +74,8 @@
       -- we would like to read directly into the buffer, but we can't
       -- be sure that the MutableByteArray# is pinned, so we have to
       -- allocate a separate area of memory and copy.
-      allocaBytes n $ \p -> do
-        r <- hGetBuf handle p n
+      allocaBytes count $ \p -> do
+        r <- hGetBuf handle p count
         memcpy_ba_ptr ptr p (fromIntegral r)
         return r
 
@@ -98,9 +98,9 @@
   | otherwise = do
       -- as in hGetArray, we would like to use the array directly, but
       -- we can't be sure that the MutableByteArray# is pinned.
-     allocaBytes n $ \p -> do
-       memcpy_ptr_ba p raw (fromIntegral n)
-       hPutBuf handle p n
+     allocaBytes count $ \p -> do
+       memcpy_ptr_ba p raw (fromIntegral count)
+       hPutBuf handle p count
 
 foreign import ccall unsafe "memcpy"
    memcpy_ptr_ba :: Ptr a -> MutableByteArray# RealWorld -> CSize -> IO (Ptr ())
diff --git a/array.cabal b/array.cabal
--- a/array.cabal
+++ b/array.cabal
@@ -1,5 +1,5 @@
 name:       array
-version:    0.3.0.2
+version:    0.3.0.3
 license:    BSD3
 license-file:    LICENSE
 maintainer:    libraries@haskell.org
@@ -15,8 +15,8 @@
 extra-source-files: include/Typeable.h
 
 source-repository head
-    type:     darcs
-    location: http://darcs.haskell.org/packages/array/
+    type:     git
+    location: http://darcs.haskell.org/packages/array.git/
 
 library
   build-depends: base >= 4.2 && < 5
@@ -40,6 +40,8 @@
       TypeSynonymInstances
   if impl(ghc)
     extensions:
+      DeriveDataTypeable,
+      StandaloneDeriving,
       Rank2Types,
       MagicHash,
       UnboxedTuples,
diff --git a/include/Typeable.h b/include/Typeable.h
--- a/include/Typeable.h
+++ b/include/Typeable.h
@@ -14,32 +14,22 @@
 #ifndef TYPEABLE_H
 #define TYPEABLE_H
 
-#define INSTANCE_TYPEABLE0(tycon,tcname,str) \
-tcname :: TyCon; \
-tcname = mkTyCon str; \
-instance Typeable tycon where { typeOf _ = mkTyConApp tcname [] }
-
 #ifdef __GLASGOW_HASKELL__
 
---  // For GHC, the extra instances follow from general instance declarations
---  // defined in Data.Typeable.
+--  // For GHC, we can use DeriveDataTypeable + StandaloneDeriving to
+--  // generate the instances.
 
-#define INSTANCE_TYPEABLE1(tycon,tcname,str) \
-tcname :: TyCon; \
-tcname = mkTyCon str; \
-instance Typeable1 tycon where { typeOf1 _ = mkTyConApp tcname [] }
+#define INSTANCE_TYPEABLE0(tycon,tcname,str) deriving instance Typeable tycon
+#define INSTANCE_TYPEABLE1(tycon,tcname,str) deriving instance Typeable1 tycon
+#define INSTANCE_TYPEABLE2(tycon,tcname,str) deriving instance Typeable2 tycon
+#define INSTANCE_TYPEABLE3(tycon,tcname,str) deriving instance Typeable3 tycon
 
-#define INSTANCE_TYPEABLE2(tycon,tcname,str) \
-tcname :: TyCon; \
-tcname = mkTyCon str; \
-instance Typeable2 tycon where { typeOf2 _ = mkTyConApp tcname [] }
+#else /* !__GLASGOW_HASKELL__ */
 
-#define INSTANCE_TYPEABLE3(tycon,tcname,str) \
+#define INSTANCE_TYPEABLE0(tycon,tcname,str) \
 tcname :: TyCon; \
 tcname = mkTyCon str; \
-instance Typeable3 tycon where { typeOf3 _ = mkTyConApp tcname [] }
-
-#else /* !__GLASGOW_HASKELL__ */
+instance Typeable tycon where { typeOf _ = mkTyConApp tcname [] }
 
 #define INSTANCE_TYPEABLE1(tycon,tcname,str) \
 tcname = mkTyCon str; \