// $ rustc ownersystem_2_borrowing.rs 
// $ ./ownersystem_2_borrowing
struct Bob {
    n: Vec<i32>
}

impl Bob {
    fn new() -> Bob {
        Bob { n: Vec::new() }
    }
}

fn func_1() {
    let n = Bob::new();
    func_2(&n);
    //is now in scope as func_2 just got a read only reference.
    println!("{}", n.n[0]);
}

fn func_2(b: &Bob) {
    println!("{}", b.n[0]);
}

fn main() {
    func_1();
}