fn lift<T>(f: impl Fn(T, T) -> T) -> impl Fn(Option<T>, Option<T>) -> Option<T> {
    move |a, b| match (a, b) {
        (Some(a), Some(b)) => Some(f(a, b)),
        _ => None
    }
}

fn main() {
    let add = lift(std::ops::Add::add);
    println!("{:?}", add(Some(1), Some(2)));
}