rust/src/test/run-pass/fact.rs

// -*- rust -*-
fn f(x: int) -> int {
    // debug!("in f:");

    log(debug, x);
    if x == 1 {
        // debug!("bottoming out");

        return 1;
    } else {
        // debug!("recurring");

        let y: int = x * f(x - 1);
        // debug!("returned");

        log(debug, y);
        return y;
    }
}

fn main() {
    assert (f(5) == 120);
    // debug!("all done");

}