rust/src/test/run-pass/use-uninit-alt2.rs

fn foo[T](&myoption[T] o) -> int {
  let int x;

  alt (o) {
    case (none[T]) { fail; }
    case (some[T](?t)) {
      x = 5;
    }
  }
  
  ret x;
}

tag myoption[T] {
  none;
  some(T);
}

fn main() {
  log(5);
}