: CompactHashMap.this.removeHelper(o) != NOT_FOUND;
    }

    @Override
    public Iterator<K> iterator() {
      return keySetIterator();
    }

    @Override
    public void clear() {
      CompactHashMap.this.clear();
    }
  }

  Iterator<K> keySetIterator() {
    Map<K, V> delegate = delegateOrNull();
    if (delegate != null) {
      return delegate.keySet().iterator();
    }