match

Rust provides pattern matching via the match keyword, which can be used like a C switch. The first matching arm is evaluated and all possible values must be covered.

fn main() {
 let number = 13;
 // TODO ^ Try different values for `number`

 println!("Tell me about {}", number);
 match number {
 // Match a single value
 1 => println!("One!"),
 // Match several values
 2 | 3 | 5 | 7 | 11 => println!("This is a prime"),
 // TODO ^ Try adding 13 to the list of prime values
 // Match an inclusive range
 13..=19 => println!("A teen"),
 // Handle the rest of cases
 _ => println!("Ain't special"),
 // TODO ^ Try commenting out this catch-all arm
 }

 let boolean = true;
 // Match is an expression too
 let binary = match boolean {
 // The arms of a match must cover all the possible values
 false => 0,
 true => 1,
 // TODO ^ Try commenting out one of these arms
 };

 println!("{} -> {}", boolean, binary);
}