protected function extract($path)
{
$parts = explode('.', $path);
if (count($parts) == 1) {
return isset($this->meta[$path]) ? $this->meta[$path] : null;
}
$current =& $this->meta;
foreach ($parts as $field) {
if (!isset($current[$field])) {
return null;
}
$current =& $current[$field];
}
return $current;
}