anchor.diff:  %%      </ul>
   %%      See type spec for details on which keys are allowed on which records.
   -spec data_get(any(), unknown) -> unknown;
  -             (name, load_data()) -> atom();
  +             (name, load_data() | load_data_skipped()) -> atom();
                (avg, load_data()) -> avg();
                (avg2, load_data()) -> avg();
                (min, load_data()) -> min();
                (max, load_data()) -> max();
                (histo, load_data()) -> histogram();
                (size_inv, ring_data()) -> avg();
  -             (avg_kr, ring_data()) -> avg_kr().
  +             (avg_kr, ring_data()) -> avg_kr();
  +             (avg | avg2 | min | max | histo | size_inv | avg_kr, load_data_skipped()) -> unknown.
   data_get(_Key, unknown) -> unknown;
   data_get(name, {load_data, Name, skip}) ->
       Name;
  
positive.code:     #ring_data{}.
  
  -spec get_default_load_data(unknown) -> unknown;
                             (load_data_list()) -> load_data().
  get_default_load_data(unknown) -> unknown;
  get_default_load_data(LoadDataList) ->
      %% name is the second element of record tuple
  
negative.code:     AvgKr.
  
  -spec get_current_estimate(Key::avg | avg2,
                             unknown | load_data() | load_data_skipped()) -> float() | unknown;
                            (Key::size_inv | avg_kr,
                             unknown | ring_data()) -> float() | unknown.
  get_current_estimate(_Key, unknown) -> unknown;
  