/**
* Unset the item at a given offset.
*
* @param mixed $key
*/
public function offsetUnset($key)
{
try {
parent::offsetUnset($key);
} catch (UnderflowException $e) {
// pass, the Multiset is empty
} catch (OutOfBoundsException $e) {
// the Multiset is not have that value. no need to scream here.
}
}
