anchor.diff:  %%                                      {stop, Reason, State}
   %% Description: Handling call messages
   %%--------------------------------------------------------------------
  +-spec handle_call({dump}, any(), #state{}) -> {reply, any(), #state{}}.
   handle_call({dump}, _From, State) ->
       Reply = {State#state.map, State#state.start},
       {reply, Reply, State};
  
positive.code: 
  -behaviour(gen_server).
  
  %% API
  -export([start_link/0]).
  
  
negative.code: %%                                      {stop, Reason, State}
  %% Description: Handling cast messages
  %%--------------------------------------------------------------------
  -spec handle_cast({log, atom(), integer()}, #state{}) -> {noreply, #state{}}.
  handle_cast({log, Tag, Size}, State) ->
      case gb_trees:lookup(Tag, State#state.map) of
          none ->
  