1pub fn add(left: u64, right: u64) -> u64 { 2 left + right 3} 4 5#[cfg(test)] 6mod tests { 7 use super::*; 8 9 #[test] 10 fn it_works() { 11 12 13 let result = add(2, 2); 14 assert_eq!(result, 4); 15 } 16}