I'm having a bit of trouble with a presenter i'm writing. In essence, I want to run a function to organise a bunch of data once, then let other functions utilise that organised data without altering it.

I've mocked up a simple example: http://laravel.io/bin/REkO8

If I run $payslip->present()->paymentsAbove(10) it alters each contract->transactions entity within $itemsByContract, so if I were to run $payslip->present()->paymentsBelow(10) it wouldn't return any items because the first function already filtered them out.

Is there anything I can do short of running something like this each time I want to use one of the functions?

private function cloneStuff()
{
	$_items = $this->itemsByContract;

	$items = new Collection;

	foreach ($_items as $_item) {
		$item = clone $_item;
		$items->push($item);
	}

	return $items;
}