   capsNormalize,
   capsFromString,
   capsToString,
-  
+
+-- * Caps Mutation
   CapsM,
   capsCreate,
   capsModify,
-  capsAppend,
-  capsMerge,
   capsAppendStructure,
   capsMergeStructure,
   capsRemoveStructure,

marshalCapsModify mkCaps (CapsM action) =
    unsafePerformIO $
        do ptr <- mkCaps
           caps <- liftM Caps $ newForeignPtr_ ptr
           result <- action caps
           caps' <- takeCaps ptr
           return (caps', result)

capsCreate :: CapsM a
           -> (Caps, a)
capsCreate action =

        {# call caps_union #} caps1 caps2 >>=
            takeCaps

-- | Creates a new caps containing all the formats that are in the
--   first but not the second.
capsSubtract :: Caps
             -> Caps
             -> Caps
