72      * @param mixed  $default The default to return if the property doesn't exist.
76     public function getField($field, $default = null)  argument
82         return $default;
89      * @param mixed  $default The default to return if the property doesn't exist.
96     public function getProperty($field, $default = null)  argument
98         return $this->getField($field, $default);
106      * @param mixed  $default     The default to return if the property doesn't exist.
110     public function getChildProperty($parentField, $field, $default = null)  argument
113             return $default;
117             return $default;
127      * @param mixed  $default The default to return if the property doesn't exist.
131     public function getErrorProperty($field, $default = null)  argument
133         return $this->getChildProperty('error', $field, $default);
140      * @param mixed  $default The default to return if the property doesn't exist.
144     public function getMetadataProperty($field, $default = null)  argument
146         return $this->getChildProperty('metadata', $field, $default);