public Range intersection(Range other) {
            if ( ! overlaps(other)) return empty;
            return new Range(from.max(other.from), to.min(other.to));
        }
Returns the intersection of this and the given range.
If the ranges does not overlap, an empty range is returned.
container-search/src/main/java/com/yahoo/search/querytransform/RangeQueryOptimizer.java