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)).    
   
   contents0_test() ->
  
positive.code: get_update_metadata(#riakc_obj{updatemetadata=UM}=Object) ->
      case UM of
          undefined ->
              try
                  get_metadata(Object)
              catch 
                  throw:no_metadata ->
                      dict:new()
              end;
          UM ->
              UM
      end.
  
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),
  