anchor.diff:  
   
   handle_call(_Request, _From, State) ->
  +    io:format("exometer_report:handle_call(??): ~p~n", [ _Request ]),
       Reply = ok,
       {reply, Reply, State}.
   
  
positive.code: 	 }).
  
  
  -record(st, { 
  	  subscribers:: [ #subscriber{} ]
  	 }).
  
  %%%===================================================================
  
negative.code: %% @end
  %%--------------------------------------------------------------------
  start_link() ->
      {ok, Opts} = application:get_env(exometer, exometer_report),
      gen_server:start_link({local, ?SERVER}, ?MODULE,  Opts, []).
  
  
  subscribe(Recipient, Probe, DataPoint, Interval) when is_pid(Recipient) ->
      gen_server:call(?MODULE, { subscribe, pid, Recipient, Probe, DataPoint, Interval });
  
  subscribe(Recipient, Probe, DataPoint, Interval) when is_atom(Recipient) ->
      gen_server:call(?MODULE, { subscribe, module, Recipient, Probe, DataPoint, Interval }).
  
  	
  %%%===================================================================
  %%% gen_server callbacks
  %%%===================================================================
  