The interval to create a span together with this interval.
Note: There is no overload for span which takes a PosInfInterval, because an interval going from negative infinity to positive infinity is not possible.
assert(NegInfInterval!Date(Date(2012, 3, 1)).span( NegInfInterval!Date(Date(1999, 7, 6))) == NegInfInterval!Date(Date(2012, 3 , 1))); assert(NegInfInterval!Date(Date(2012, 3, 1)).span( NegInfInterval!Date(Date(2013, 1, 12))) == NegInfInterval!Date(Date(2013, 1 , 12)));
Returns an interval that covers from the earliest time point of two intervals up to (but not including) the latest time point of two intervals.