public function addGroupHeader(array $properties = array()) { foreach ($this->optionValidators as $validator) { $validator->validate(array_add(array(), $option, $value)); } $this->markFunctionTypeProperty($properties); if (!isset($this->groupHeaderOptions['groupHeaders'])) { $this->groupHeaderOptions['groupHeaders'] = array(); } array_push($this->groupHeaderOptions['groupHeaders'], $properties); return $this; }