prop_foldr_foldl :: BagTest Int bag => bag Int -> bag Int -> Bool
prop_foldr_foldl bag xs =
    foldr (:) [] xs == toOrdList xs
    &&
    foldl (flip (:)) [] xs == Prelude.reverse (toOrdList xs)
prop_foldr_foldl :: BagTest Int bag => bag Int -> bag Int -> Bool
prop_foldr_foldl bag xs =
    foldr (:) [] xs == toOrdList xs
    &&
    foldl (flip (:)) [] xs == Prelude.reverse (toOrdList xs)
prop_foldr_foldl bag xs =
    foldr (:) [] xs == toOrdList xs
    &&
    foldl (flip (:)) [] xs == Prelude.reverse (toOrdList xs)