rust/src/test/run-pass/tail-cps.rs

// -*- rust -*-
fn checktrue(rs: bool) -> bool { assert (rs); ret true; }

fn main() { let k = checktrue; evenk(42, k); oddk(45, k); }

fn evenk(n: int, k: extern fn(bool) -> bool) -> bool {
    debug!{"evenk"};
    log(debug, n);
    if n == 0 { ret k(true); } else { ret oddk(n - 1, k); }
}

fn oddk(n: int, k: extern fn(bool) -> bool) -> bool {
    debug!{"oddk"};
    log(debug, n);
    if n == 0 { ret k(false); } else { ret evenk(n - 1, k); }
}