comprehensive-rust/src/pattern-matching.md

Pattern Matching

The match keyword let you match a value against one or more patterns. The comparisons are done from top to bottom and the first match wins.

The patterns can be simple values, similarly to switch in C and C++:

fn main() {
    let input = 'x';

    match input {
        'q'                   => println!("Quitting"),
        'a' | 's' | 'w' | 'd' => println!("Moving around"),
        '0'..='9'             => println!("Number input"),
        _                     => println!("Something else"),
    }
}

The _ pattern is a wildcard pattern which matches any value.