anchor.diff:  	      end
         end, false, Nodes).
   
  --spec lookup(atom(), any()) -> {ok, any()} | error.
  +-spec lookup(atom(), any()) -> {ok, any()} | any().
   lookup(Name, Key) ->
       lookup(Name, Key, undefined).
   
  --spec lookup(atom(), any(), read_fun() | undefined) -> {ok, any()} | error.
  +-spec lookup(atom(), any(), read_fun() | undefined) -> {ok, any()} | any().
   lookup(Name, Key, ReadFun) ->
       try ets:lookup(Name, Key) of
   	[{_, Val, _} = Obj] ->
  
positive.code: 	    Val = case ReadFun() of
  		      {ok, Val1} -> {ok, Val1};
  		      error -> error;
  		      Other -> {error, Other}
  		  end,
  	    case Val of
  
negative.code: 			 ok -> Val;
  			 {ok, Val1} -> {ok, Val1};
  			 error -> error;
  			 {error, notfound} -> error;
  			 Other -> {error, Other}
  		     end,
  	    case NewVal of
  