anchor.diff:                  let alert = new UIAlertView (Title = "Room Deleted", Message = "This room no longer exists.")
                   alert.AddButton "Leave" |> ignore
                   alert.Show ()
  -                alert.Clicked.Add(fun _ -> 
  -                    Async.startInBackgroundWithContinuation
  -                        (fun _ -> DB.removeChatHistoryById room.Id)
  -                        (fun _ ->
  -                            controller.Leave room.Id
  -                            Navigation.navigate "/home" None
  -                        )
  -                )
  +                alert.Clicked.Add(fun _ -> leave())
               | error -> controller.HandleApiFailure error)
   
   
  
positive.code:     let join (room:Entity) =
          let _, controller =
              let controllerAdd = new ChatRoomViewController (room)
              controllerAdd.Leave <- leave
              rooms.AddOrUpdate (
                      room.Id,
                      (fun _ -> room, controllerAdd),
  
negative.code:                             | Api.ApiOk _ -> starred <- not starred
                              | error -> controller.HandleApiFailure error 
                          )
                  | 1 -> leave ()
                  | _ -> ()
              )))
  
  