private function namespaceBlock() {
    $node = new StatementBlockNode();
    $this->matchHidden($node);
    while ($this->currentType !== NULL) {
      if ($this->currentType === T_NAMESPACE && !$this->isLookAhead(T_NS_SEPARATOR)) {
        break;
      }
      $node->addChild($this->topStatement());
      $this->matchHidden($node);
    }
    $this->matchHidden($node);
    return $node;
  }