static boolean nl_extends(PsiBuilder b, int l) {
    if (!recursion_guard_(b, l, "nl_extends")) return false;
    boolean r;
    r = nl_non_empty_extends(b, l + 1);
    if (!r) r = empty_extends_clause(b, l + 1);
    return r;
  }
static boolean nl_extends(PsiBuilder b, int l)