rust/src/test/run-pass/alt-join.rs

use std;
import option;

fn foo<T>(y: option<T>) {
    let mut x: int;
    let mut rs: ~[int] = ~[];
    /* tests that x doesn't get put in the precondition for the
       entire if expression */

    if true {
    } else {
        alt y {
          none::<T> => x = 17,
          _ => x = 42
        }
        rs += ~[x];
    }
    return;
}

fn main() { debug!{"hello"}; foo::<int>(some::<int>(5)); }