anchor.diff:  %%
   %% APIs
   %%
  -test() -> ng.
  +test() ->
  +	remove_all(),
  +
  +	T1 = add("0123"),
  +	ok = check("0123", T1),
  +	ng = check("0124", T1),
  +
  +	T2 = add("0123", -1),
  +	ng = check("0123", T2),
  +	ng = check("0124", T2),
  +
  +	ok.
   
   add(Id) ->
   	Reply = gen_server:call(?MODULE, {add, Id}).
  +	{ok, V} = Reply,
  +	V.
  +
  +add(Id, ExpireUnixtime) ->
  +	Reply = gen_server:call(?MODULE, {add, Id, ExpireUnixtime}),
  +	{ok, V} = Reply,
  +	V.
   
   remove_all() ->
   	Reply = gen_server:call(?MODULE, {remove_all}).
  
positive.code: 	MetaData = riakc_obj:get_update_metadata(Obj1),
  	io:format("~p~n", [MetaData]),
  
  	MD1 = riakc_obj:set_secondary_index(MetaData, [{{integer_index, "expire_unixtime"}, [V#loc.map_id]}]),
  
  	Obj2 = riakc_obj:update_metadata(Obj1, MD1),
  
  	riakc_pb_socket:put(Pid, Obj2),
  	{reply, ok, State};
  
  handle_call({remove_all}, From, State) ->
  	Pid = State,
  
negative.code: 		{ok, Fetched1} -> true;
  		{error, notfound} -> false
  	end.
  
  impl_online(Pid, Id, Token) when is_list(Id) ->
  	BinId = erlang:list_to_binary(Id),
  