TimeStamp operator+(const TimeDelta &t) const { return TimeStamp(usec+t.raw()); }
TimeStamp &operator+=(const TimeDelta &t) { usec+=t.raw(); return *this; }
TimeStamp operator+(const TimeDelta &t) const { return TimeStamp(usec+t.raw()); }
TimeStamp &operator+=(const TimeDelta &t) { usec+=t.raw(); return *this; }