anchor.diff:           trace/2,
            replay/2,
            reset/0,
  +         enable/0,
            identify/1,
            print/0,
            perform_preloads/0]).
  
positive.code:         false ->
              %% This is not a replay, so store the current trace.
              replay_debug("recording trace to file.", []),
              #state{trace=[], blocked_processes=[], identifier=undefined};
          _ ->
              %% Mark that we are in replay mode.
              partisan_config:set(replaying, true),
  
negative.code: %% @doc Replay trace.
  replay(Type, Message) ->
      gen_server:call({global, ?MODULE}, {replay, Type, Message}, infinity).
  
  %% @doc Enable trace.
  enable() ->
      gen_server:call({global, ?MODULE}, enable, infinity).
  
  %% @doc Reset trace.
  reset() ->
  