docs: public static IntervalCounter get(Registry registry, Id id) {
      ConcurrentMap<Id, Object> state = registry.state();
      Object c = Utils.computeIfAbsent(state, id, i -> new IntervalCounter(registry, i));
      if (!(c instanceof IntervalCounter)) {
        Utils.propagateTypeError(registry, id, IntervalCounter.class, c.getClass());
        c = new IntervalCounter(new NoopRegistry(), id);
      }
      return (IntervalCounter) c;
    }