Rust for C-Programmers

21.11 OR Patterns and Combined Guards

Use the | operator to combine multiple patterns into a single match arm:

fn check_char(c: char) {
    match c {
        'a' | 'A' => println!("Found an 'a'!"),
        _ => println!("Not an 'a'"),
    }
}

fn main() {
    check_char('A');
    check_char('z');
}

You can also mix guards with OR patterns:

fn main() {
    let x = 4;
    let b = false;
    match x {
        // Matches if x is 4, 5, or 6, AND b == true
        4 | 5 | 6 if b => println!("yes"),
        _ => println!("no"),
    }
}

The guard (if b) applies only after the pattern itself matches one of 4, 5, or 6.