prop_fromSeq :: BagTest Int bag => bag Int -> Seq Int -> Bool
prop_fromSeq bag xs =
    fromSeq xs `asTypeOf` bag === S.foldr insert empty xs
prop_fromSeq :: BagTest Int bag => bag Int -> Seq Int -> Bool
prop_fromSeq bag xs =
    fromSeq xs `asTypeOf` bag === S.foldr insert empty xs
prop_fromSeq bag xs =
    fromSeq xs `asTypeOf` bag === S.foldr insert empty xs