gistfile1.txt

(* this *)
sub map(xs, f, go result = list()) {
    if empty?(xs) {
        result;
    } else {
        go(tail(result), f, f(head(xs)) :: result);
    }
}

(* is transformed into this *)
sub map(xs, f) {
    sub __go(xs, f, result) {
        if empty?(xs) {
            result;
        } else {
            __go(tail(result), f, f(head(xs)) :: result);
        }
    }
    __go(xs, f, list());
}