Canonical form for synchronous requests

The next example show the canonical form for when you want to code a pattern that specifies two or more synchronous requests.

event RequestA { integer requestId; ... }
event ResponseA { integer requestId; ... }
event RequestB { integer requestId; ... }
event ResponseB { integer requestId; ... }

monitor Client {
   action doWork() {
      //do some processing
      integer requestId := integer.getUnique();
      route RequestA(requestId,...);
      ResponseA ra;
      on ResponseA(id=requestId):ra doWork2(ra);
   }
   action doWork2(ResponseA ra) {
      //do some more processing
      integer requestId := integer.getUnique();
      route RequestB(requestId,...);
      Response rb;
      on ResponseB(id=requestId):rb doWork3(rb);
   }
   action doWork3(ResponseB rb) {
      //do yet more processing
   }
}