How to make [std::operator""s] visible in a namespace?

If you want to have all the chrono literals then you can use

using namespace std::chrono_literals;

If you just want operator""s then you can use

using std::chrono_literals::operator""s;

Do note that at least on coliru gcc issues a warning for the above line but clang does not. To me there should be no warning. I have asked a follow up question about this at Should a using command issue a warning when using a reserved identifier?