private function varClass(Node $class_name) {
    $colon_node = new PartialNode();
    $this->mustMatch(T_DOUBLE_COLON, $colon_node);
    if ($this->currentType === T_STRING) {
      $method_name = $this->mustMatchToken(T_STRING);
      return $this->classMethodCall($class_name, $colon_node, $method_name);
    }
    else {
      return $this->classVariable($class_name, $colon_node);
    }
  }