20 General utilities library [utilities]

20.17 Time utilities [time]

20.17.7 Clocks [time.clock]

20.17.7.3 Class high_resolution_clock [time.clock.hires]

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:
  using rep        = unspecified;
  using period     = ratio<unspecified, unspecified>;
  using duration   = chrono::duration<rep, period>;
  using time_point = chrono::time_point<unspecified, duration>;
  static constexpr bool is_steady = unspecified;

  static time_point now() noexcept;
};