anchor.diff:  -export([start_link/1, activate/1, deactivate/0, start_gossip_task/2, stop_gossip_task/1, remove_all_tombstones/0]).
   
   % interaction with the ring maintenance:
  --export([rm_my_range_changed/3, rm_send_new_range/4]).
  +-export([rm_filter_slide_msg/3, rm_send_activation_msg/4, rm_my_range_changed/3, rm_send_new_range/4]).
   
   % testing
   -export([tester_create_state/9, is_state/1]).
  
positive.code: 
  % called by dht_node_join, results in on_active
  -spec activate(Range::intervals:interval()) -> ok.
  activate(MyRange) ->
      Pid = pid_groups:get_my(gossip2),
      comm:send_local(Pid, {activate_gossip, MyRange}).
  
  
  %% @doc Deactivates all gossip processes.
  
negative.code:     Msg = {?send_to_group_member, gossip2, {remove_all_tombstones}},
      bulkowner:issue_bulk_owner(uid:get_global_uid(), intervals:all(), Msg).
  
  
  %% @doc Checks whether the received notification is a {slide_finished, succ} or
  %%      {slide_finished, pred} msg. Used as filter function for the ring maintanance.
  -spec rm_filter_slide_msg(Neighbors, Neighbors, Reason) -> boolean() when
                            Neighbors :: nodelist:neighborhood(),
                            Reason :: rm_loop:reason().
  rm_filter_slide_msg(_OldNeighbors, _NewNeighbors, Reason) ->
          Reason =:= {slide_finished, pred} orelse Reason =:= {slide_finished, succ}.
  
  %% @doc Sends the activation message to the behaviour module (this module)
  %%      Used to subscribe to the ring maintenance for {slide_finished, succ} or
  %%      {slide_finished, pred} msg.
  -spec rm_send_activation_msg(Subscriber, ?MODULE, Neighbours, Neighbours) -> ok when
                               Subscriber :: pid(),
                               Neighbours::nodelist:neighborhood().
  rm_send_activation_msg(_Pid, ?MODULE, _OldNeighbours, NewNeighbours) ->
      %% io:format("Pid: ~w. Self: ~w. PidGossip: ~w~n", [Pid, self(), Pid2]),
      MyRange = nodelist:node_range(NewNeighbours),
      Pid = pid_groups:get_my(gossip2),
      comm:send_local(Pid, {activate_gossip, MyRange}).
  
  
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  