code: def __bad_transition(self, state):
          
          statemsg = ""
          oldState = self.stateNames[ self.get_state() ]
          newState = self.stateNames[ state ]
          msg = "Invalid state transition (%s -> %s)" \
                " for breakpoint at address %s"
          msg = msg % (oldState, newState, HexDump.address(self.get_address()))
          raise AssertionError(msg)
docs: Raises an C{AssertionError} exception for an invalid state transition.
  
          @see: L{stateNames}
  
          @type  state: int
          @param state: Intended breakpoint state.
  
          @raise Exception: Always.