The interval to merge with this interval.
Note: There is no overload for merge which takes a NegInfInterval, because an interval going from negative infinity to positive infinity is not possible.
assert(PosInfInterval!Date(Date(1996, 1, 2)).merge( PosInfInterval!Date(Date(1990, 7, 6))) == PosInfInterval!Date(Date(1990, 7 , 6))); assert(PosInfInterval!Date(Date(1996, 1, 2)).merge( PosInfInterval!Date(Date(1999, 1, 12))) == PosInfInterval!Date(Date(1996, 1 , 2)));
Returns the union of two intervals