/**
* Construction of a collection
*
* @param array|string $items_collection The array of the collection content (optional)
* @throws \InvalidArgumentException if the collection argument is not an array
*/
public function __construct($items_collection = array())
{
if (empty($items_collection)) {
throw new \InvalidArgumentException(sprintf('Creation of a "%s" instance with no items collection is not allowed!', __CLASS__));
}
if (!is_array($items_collection)) {
$items_collection = array($items_collection);
}
parent::__construct($items_collection);
}
