public static function isCallable($callback, $allowGlobalFunctions = FALSE, $silent = TRUE)
{
if ($callback instanceof \Closure) {
return $callback;
} elseif (is_string($callback) && $allowGlobalFunctions || self::isCallableArray($callback)) {
return is_callable($callback) ? $callback : NULL;
} elseif ($silent) {
return NULL;
}
throw new \InvalidArgumentException('Invalid callback argument');
} /**
* @param mixed $content
* @param bool $includeTextNodes
* @param int $limit
* @return array|\Traversable null
*/
private function getNodeList($content, $includeTextNodes = TRUE, $limit = -1)
{
if ($callback = Constraints::isCallable($content)) {
$content = $callback();
}
if ($content instanceof \DOMElement) {
return array($content);
} elseif ($includeTextNodes && Constraints::isNode($content)) {
return array($content);
} elseif (Constraints::isNodeList($content)) {
return $this->getLimitedArray($content, $limit);
}
return NULL;
}