anchor.diff:      true ->
         ok
     end.
  +
  +create_mf(Name, Help, Type, Data) ->
  +  prometheus_model_helpers:create_mf(Name, Help, Type, ?MODULE, Data).
  
positive.code:          register/1,
           deregister/1,
           collect_mf/2,
           collect_metrics/3]).
  
  -include("prometheus.hrl").
  -behaviour(prometheus_collector).
  
negative.code:   ets:match_delete(?TABLE, {{Registry, '_', '_'}, '_'}).
  
  collect_mf(Callback, Registry) ->
    [Callback(create_mf(Name, gauge, Help, {Labels, Registry})) ||
      [Name, Labels, Help, _] <- prometheus_metric:metrics(?TABLE, Registry)].
  
  collect_metrics(Name, {Labels, Registry}) ->
    [gauge_metric(lists:zip(Labels, LabelValues), Value) ||
      [LabelValues, Value] <- ets:match(?TABLE, {{Registry, Name, '$1'}, '$2'})].
  
  %%====================================================================
  