The module SharedRep provides the part of the implementation of shared objects SharedObj.T that is independent of any particular shared object. It is not intended that any client accesses any of the fields of the SharedObj.T directly. Only the generated code references this interface.

INTERFACE SharedObjRep;

IMPORT SharedObj, RdWrMutex, Thread, EventWireRep, EventCounter,
       WeakRefList, Wr, Rd, Event, EventStubLib, ThreadF;

TYPE WireRep = EventWireRep.T;

The wire representation of our objects is represented using the WireRep provided by the event package.

REVEAL
  SharedObj.T = SharedObj.Public BRANDED SharedObj.Brand OBJECT
      (* Is it ok, or has an update raised a fatal error? *)
      ok      : BITS 1 FOR BOOLEAN := TRUE;

      (* Who is performing an update right now? *)
      updating: ThreadF.Id := -1;

      (* A shareable lock. *)
      mu    : RdWrMutex.T := NIL;

      (* The wire representation of the object. *)
      wrep  : WireRep := EventWireRep.NullT;

      (* Current sequence number. *)
      seqNoCnt: EventCounter.T := NIL;

      (* How fast do we require updates? *)
      timeliness: SharedObj.Timeliness := 0;

      (* the currently registered callbacks on this object.  Stored
         as "WeakRef.T"s *)
      callbacks: WeakRefList.T := NIL;
    METHODS
      applyUpdate(ev: Event.T; h: EventStubLib.Handle)
        RAISES {SharedObj.Error, SharedObj.Fatal, Event.Error,
                Rd.Failure, Wr.Failure, Thread.Alerted};
    END;

PROCEDURE ToText(self: SharedObj.T): TEXT;

END SharedObjRep.