@@ -136,7 +136,7 @@ lookup k = M.lookup k . unpack
136136{-# INLINE lookup #-}
137137
138138-- | /O(log n)/ Return the value to which the specified key is mapped,
139−-- or 'Nothing' if this map contains no mapping for the key.
139+-- or mempty if this map contains no mapping for the key.
140140lookupM :: (Eq k, Hashable k, Monoid v) => k -> MonoidalHashMap k v -> v
141141lookupM k = fromMaybe mempty . M.lookup k . unpack
142142{-# INLINE lookupM #-}