alias.rs

fn main() {
    let mut x = 1;
    let mut y = 0;
    {
      let z = alias(&mut x,&mut y); 
      *z = 1;
    }
    println!("y is now {}", y);
}

fn alias<'a>(x:&'a mut i32, y:&'a mut i32) -> &'a mut i32 {
    if *x == 0 {
        x
    } else {
        y
    }
}