interface Intf {
  in void evt();
  behaviour {
    on evt: {}
  }
}

component Comp {
  provides Intf p;
  requires Intf r;
  behaviour {
    on p.evt(): {}
  }
}

component System {
  provides Intf p1;
  requires Intf r1;
  
  system {
    Comp comp1;
    Comp comp2;
    Comp comp3;
    comp1.p <=> comp2.p;
    comp1.r <=> comp2.r;
    p1 <=> comp3.r;
    r1 <=> comp3.p;
  }
}