anchor.diff:                               State2 = setelement(17, State1, 0),
                                inc_session_count(State2).
   
  --spec session_count(state()) -> state().
  +-spec session_count(state()) -> non_neg_integer().
   session_count(State) -> element(18, State).
   -spec inc_session_count(state()) -> state().
   inc_session_count(State) -> setelement(18, State, session_count(State) + 1).
  
positive.code: -compile({inline, [dest_ip/1, dest_port/1, local_listen_port/1, channel/1,
                     socket/1, set_socket/2,
                     started/1,
                     s_msg_count/1, inc_s_msg_count/1,
                     r_msg_count/1, inc_r_msg_count/1,
                     msg_queue/1, set_msg_queue/2,
                     msg_queue_len/1, set_msg_queue_len/2,
                     desired_bundle_size/1, set_desired_bundle_size/2,
  
negative.code:     State3 = inc_r_msg_count(State2, length(Msg)),
      setelement(20, State3, NewList).
  
  -spec save_n_msgs([msg_or_tag()] | msg_or_tag(), fun((state(), [msg_or_tag()]) -> state()), state()) -> state().
  save_n_msgs(Msg, SaveFun, State) when is_tuple(Msg) ->
      save_n_msgs([{single, Msg}], SaveFun, State);
  save_n_msgs(Msgs, SaveFun, State) when is_list(Msgs) ->
  