Objects of class high_resolution_clock represent clocks with the shortest tick period. high_resolution_clock may be a synonym for system_clock or steady_clock.
class high_resolution_clock { public: typedef unspecified rep; typedef ratio<unspecified, unspecified> period; typedef chrono::duration<rep, period> duration; typedef chrono::time_point<unspecified, duration> time_point; static constexpr bool is_steady = unspecified; static time_point now() noexcept; };