anchor.diff:      %% Wait for responses.
       receive
           {ok, X, V} ->
  +            %% Log result.
  +            Debug1 = sys:handle_debug(Debug,
  +                                      fun write_debug/3,
  +                                      ?MODULE,
  +                                      {ok, X, V}),
  +
               %% Update cache.
               Cache = orddict:store(X, V, DefaultedCache),
   
  
positive.code: %%%===================================================================
  
  start_link(Module, Args) ->
      proc_lib:start_link(?MODULE, start, [self(), Module, Args]).
  
  %%%===================================================================
  %%% Callbacks
  %%%===================================================================
  
  %% @doc TODO
  start(Parent, Module, Args) ->
      %% Initialize state.
      {ok, State} = case Module:init(Args) of
          {ok, InitState} ->
  
negative.code:         {error, Reason} ->
              exit(Reason)
      end,
  
      %% Create debugging structure.
      Debug = sys:debug_options([]),
  
      loop(Parent, Debug, Module, State, orddict:new()).
  
  %% @doc TODO
  loop(Parent, Debug, Module, State0, Cache0) ->
      %% Get self.
      Self = self(),
  
  