anchor.diff:              {ok, State} = Module:process(RealizedCache, ReadState),
   
               %% Wait.
  -            loop(Module, State, Cache)
  +            loop(Parent, Debug1, Module, State, Cache)
       end.
  +
  +%% @private
  +write_debug(Dev, Event, Name) ->
  +        io:format(Dev, "~p event = ~p~n", [Name, Event]).
  
positive.code:     %% Wait for responses.
      receive
          {ok, X, V} ->
              %% Update cache.
              Cache = orddict:store(X, V, DefaultedCache),
  
  
negative.code: -export([start_link/2]).
  
  %% Callbacks
  -export([init/3]).
  
  %%%===================================================================
  %%% Behaviour
  