std::chrono::time_of_day<Duration>::time_of_day

time_of_day() = default;
 (1) 
explicit constexpr time_of_day(precision since_midnight) noexcept;
 (2)

Constructs a time_of_day object.

1) Default constructor leaves the object uninitialized.
2) Constructs a time_of_day object in 24 hour format corresponding to since_midnight after 00:00:00. As applicable:
  • hours() returns the integral number of hours since_midnight is after 00:00:00.
  • minutes() returns the integral number of minutes since_midnight is after (00:00:00 + hours()).
  • seconds() returns the integral number of seconds since_midnight is after (00:00:00 + hours() + minutes()).
  • subseconds() returns the integral number of fractional seconds since_midnight is after (00:00:00 + hours() + minutes() + seconds()).

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