interface RGuardthreetopon
{
  in void e();
  out void a();
  behaviour {
    on e: illegal;
  }
}

interface IGuardthreetopon
{
  in void e();
  in void t();
  in void s();
  out void a();
  behaviour
    {
      bool b = false;
      [true ] {
        on e: [b] { a; }
        on e: [!b] { a; }
      }
      on t: [!b] { a; }
      on t: [b] { a; }
      on t: [!b] { a; }
      on s: { a; }
    }
}

component Guardthreetopon
{
  provides IGuardthreetopon i;
  requires RGuardthreetopon r;

  behaviour
    {
      bool b = false;
      [true] {
        on i.e(): [b] { i.a(); }
        on i.e(): [!b] { bool c = true; if (c) i.a(); }
      }
      on i.t(): [b] i.a();
      on r.a(): {}
      on i.t(): [!b] i.a();
      on i.s(): i.a();
    }
}