anchor.diff:           terminate/2,
            code_change/3]).
   
  --record(state, {trace=[], identifier=undefined, current_trace_file=undefined}).
  +-record(state, {previous_trace=[],
  +                trace=[], 
  +                replay=false,
  +                identifier=undefined, 
  +                current_trace_file=undefined}).
   
   %%%===================================================================
   %%% API
  
positive.code: handle_call({identify, Identifier}, _From, State) ->
      lager:info("~p: identifying trace: ~p", [?MODULE, Identifier]),
      {reply, ok, State#state{identifier=Identifier}};
  handle_call(print, _From, #state{trace=Trace, current_trace_file=CurrentTraceFile}=State) ->
      lager:info("~p: printing trace", [?MODULE]),
  
      lists:foldl(fun({Type, Message}, Count) ->
  
negative.code:     end, 1, Trace),
  
      %% Write trace.
      case Replay of 
          true ->
              lager:info("~p: not writing trace, replay mode.", [?MODULE]),
              ok;
          false ->
              lager:info("~p: writing trace.", [?MODULE]),
  
              lists:foreach(fun(Line) ->
                  io:format(CurrentTraceFile, "~p~n", [Line])
                  end, Trace)
      end,
  
      {reply, ok, State};
  handle_call(Msg, _From, State) ->
  