2 Checks for `match vec[idx]` or `match vec[n..m]`.
5 This can panic at runtime.
9 let arr = vec![0, 1, 2, 3];
13 0 => println!("{}", 0),
14 1 => println!("{}", 3),
21 let arr = vec![0, 1, 2, 3];
25 Some(0) => println!("{}", 0),
26 Some(1) => println!("{}", 3),