/**
* {@inheritdoc}
*/
public function sortOn($fn, $order = Sort\ASC)
{
return new self(Sort\comparison($this->items, $fn, $order));
}
/**
* {@inheritdoc}
*/
public function sortOn($fn, $order = Sort\ASC)
{
$this->items = Sort\comparison($this->items, $fn, $order);
return $this;
}
