23 General utilities library [utilities]

23.17 Time utilities [time]

23.17.6 Class template time_­point [time.point]

23.17.6.3 time_­point arithmetic [time.point.arithmetic]

constexpr time_point& operator+=(const duration& d);
Effects: As if by: d_­ += d;
Returns: *this.
constexpr time_point& operator-=(const duration& d);
Effects: As if by: d_­ -= d;
Returns: *this.