depGraphLookup :: Ord a =>
                  DepGraph a b c -> a -> Maybe (b, Set.Set a, Set.Set c)
depGraphLookup gr x = Map.lookup x $ dataMap gr
depGraphLookup :: Ord a =>
                  DepGraph a b c -> a -> Maybe (b, Set.Set a, Set.Set c)
depGraphLookup gr x = Map.lookup x $ dataMap gr
depGraphLookup gr x = Map.lookup x $ dataMap gr