interface ihello
{
  in bool hello();

  behaviour
  {
    on hello: reply(false);
  }
}

component hello_tail_recursive_function
{
  provides ihello h;

  behaviour
  {
    bool b = false;
    void f() {
      b = !b;
      if(b) f();
    }
    on h.hello(): {f(); reply(b);}
  }
}