------------------------------------------------------------------------------
-- |Monoid Laws
prop_leftId :: ArbMapSyntax String Int -> Bool
prop_leftId a = runMap (mempty `mappend` m) == runMap m
  where m = unArbSyntax a
prop_leftId :: ArbMapSyntax String Int -> Bool
prop_leftId a = runMap (mempty `mappend` m) == runMap m
  where m = unArbSyntax a
prop_leftId a = runMap (mempty `mappend` m) == runMap m
  where m = unArbSyntax a