anchor.diff:      tester:unregister_value_creator({typedef, rdht_tx, encoded_value}),
       true.
   
  -tester_type_check_util(_Config) ->
  +tester_type_check_histogram(_Config) ->
       Count = 500,
       config:write(no_print_ring_data, true),
       tester:register_type_checker({typedef, histogram, histogram}, histogram, tester_is_valid_histogram),
       tester:register_value_creator({typedef, histogram, histogram}, histogram, tester_create_histogram, 2),
  +    %% [{modulename, [excludelist = {fun, arity}]}]
  +    Modules =
  +        [ {histogram,
  +           [ {find_smallest_interval, 1}, % private API, needs feeder
  +             {merge_interval, 2}, % private API, needs feeder
  +             {find_largest_window, 2} % needs feeder for correct window size
  +           ],
  +           [ {resize, 1}, % needs feeder
  +             {sliding_window_max, 7} % fed by find_largest_window/2
  +           ]}
  +        ],
  +    _ = [ tester:type_check_module(Mod, Excl, ExclPriv, Count)
  +          || {Mod, Excl, ExclPriv} <- Modules ],
  +    tester:unregister_type_checker({typedef, histogram, histogram}),
  +    tester:unregister_value_creator({typedef, histogram, histogram}),
  +    true.
  +
  +tester_type_check_util(_Config) ->
  +    Count = 500,
  +    config:write(no_print_ring_data, true),
       %% [{modulename, [excludelist = {fun, arity}]}]
       Modules =
           [ {comm,
  
positive.code:            ], []},
            %% {fix_queue, [], []}, %% queue as builtin type not supported yet
  
            {histogram,
             [ {find_smallest_interval, 1}, % private API, needs feeder
               {merge_interval, 2}, % private API, needs feeder
               {find_largest_window, 2} % needs feeder for correct window size
             ],
             [ {resize, 1}, % needs feeder
               {sliding_window_max, 7} % fed by find_largest_window/2
             ]},
            {msg_queue, [], []},
            {pdb, [], []},
            {pid_groups,
  
negative.code:         ],
      _ = [ tester:type_check_module(Mod, Excl, ExclPriv, Count)
            || {Mod, Excl, ExclPriv} <- Modules ],
  %% feeders are found automatically - sample explicit call would be:
  %%    tester:test(util, readable_utc_time, 1, 25, [with_feeder]),
  
  