Binding

Indirectly accessing a variable makes it impossible to branch and use that variable without re-binding. match provides the @ sigil for binding values to names:

1. // A function `age` which returns a `u32`.
2. fn age() -> u32 {
3. 15
4. }

6. fn main() {
7. println!("Tell me type of person you are");

9. match age() {
10. 0             => println!("I'm not born yet I guess"),
11. // Could `match` 1 ... 12 directly but then what age
12. // would the child be? Instead, bind to `n` for the
13. // sequence of 1 .. 12. Now the age can be reported.
14. n @ 1  ... 12 => println!("I'm a child of age {:?}", n),
15. n @ 13 ... 19 => println!("I'm a teen of age {:?}", n),
16. // Nothing bound. Return the result.
17. n             => println!("I'm an old person of age {:?}", n),
18. }
19. }

See also:

functions