<?php
##
#	v3_sort; Abstract class for decorate/sort/undecorate sorts.
#	         Extending classes supply their own {un}decorate
#	         and compare methods.
##
	abstract class v3_sort
	{
		abstract public function   decorate(&$item);
		abstract public function undecorate(&$item);
		abstract public function compare($item_a, $item_b);

		public function sort(&$array)
		{
			if(($num_entries = count($array)) === 0)
				return true;

			foreach($array as &$item)
				$this->decorate($item);

			if(usort($array, array($this, 'compare')) === false)
				return false;

			foreach($array as &$item)
				$this->undecorate($item);

			return true;
		}
	}
?>