Method intersect

regex/regex-syntax/src/hir/interval.rs:365–373

Intersect this range with the given range and return the result. If the intersection is empty, then this returns `None`.

(&self, other: &Self)

    ///
    /// If the intersection is empty, then this returns `None`.
    fn intersect(&self, other: &Self) -> Option<Self> {
        let lower = cmp::max(self.lower(), other.lower());
        let upper = cmp::min(self.upper(), other.upper());
        if lower <= upper {
            Some(Self::create(lower, upper))
        } else {
            None
        }
    }

    /// Subtract the given range from this range and return the resulting
    /// ranges.