anchor.diff:      ?assertEqual([], get_metadatas(O)),
       ?assertEqual([], get_values(O)),
       ?assertEqual([], get_contents(O)),
  -    ?assertThrow(no_metadata, get_metadata(O)),
       ?assertThrow(no_value, get_value(O)).
   
   contents1_test() ->
  
positive.code: 
  %% @doc Assert that this riakc_obj has no siblings and return its
  %%       associated metadata.  This function will throw `siblings' if
  %%       the object has siblings (value_count() > 1), or `no_metadata'
  %%       if the object has no metadata.
  %% @throws siblings | no_metadata
  -spec get_metadata(Object::riakc_obj()) -> metadata().
  get_metadata(O=#riakc_obj{}) ->
      case get_contents(O) of
          [] ->
              throw(no_metadata);
          [{MD,_V}] ->
              MD;
          _ ->
  
negative.code: 
  %% @doc Return the content type of the value if there are no siblings.
  %% @see get_metadata/1
  %% @throws siblings
  -spec get_content_type(Object::riakc_obj()) -> content_type().
  get_content_type(Object=#riakc_obj{}) ->
      UM = get_metadata(Object),
  