anchor.diff:  //            ()
   //    end
   
  -    type FSS(port:int) = class
  +    /// Function to handle an exception raised during the handling of a request.
  +    type ErrorHandler = System.Exception -> Response
  +
  +    type FSS(port:int, errorHandler:ErrorHandler option) = class
           let mutable minLogLevel = 4
           let myLock = (1,2) // Need object not value for locking
           
  
positive.code:         let lockThreadTracker() = Monitor.Enter(myLock)
          let unlockThreadTracker() = Monitor.Exit(myLock)
          let tcpListener = new TcpListener(System.Net.IPAddress.Any,port)
  
          ///
          let log level (s:string) =
  
negative.code:                                     this.doPost id bs sw path headers 
                              | _ -> Response(500,"text/html")
                      with x ->
                          errorHandler x
                                 
                  // Start constructing the reply starting with the response code   
                  sprintf "fss%d: finished getting connection, sending response code\n" id |> log 1
  