prop_null_size :: BagTest Int bag => bag Int -> bag Int -> Bool
prop_null_size bag xs =
    null xs == (size xs == 0)
    &&
    size xs == Prelude.length (toOrdList xs)
prop_null_size :: BagTest Int bag => bag Int -> bag Int -> Bool
prop_null_size bag xs =
    null xs == (size xs == 0)
    &&
    size xs == Prelude.length (toOrdList xs)
prop_null_size bag xs =
    null xs == (size xs == 0)
    &&
    size xs == Prelude.length (toOrdList xs)