Sort

gistfile1.txt

<?php

class Test
{
    public $id;
    public function __construct($id)
    {
        $this->id = $id;
    }
}

class Sort
{
    public $priorities;
    public $objects;

    public function __construct()
    {
        $this->priorities = array( 2, 4, 7, 13 );
        $this->objects = array( new Test(4), new Test(13), new Test(2), new Test(7) );
    }

    public function doSort()
    {
        usort( $this->objects, array( $this, 'compare' ) );
    }

    public function compare( Test $first, Test $second )
    {
        $firstPriority = array_search( $first->id, $this->priorities );
        $secondPriority = array_search( $second->id, $this->priorities );

        if ( $firstPriority == $secondPriority )
        {
            return 0;
        }

        return ( $firstPriority < $secondPriority ) ? -1 : 1;
    }
}

$sort = new Sort();
$sort->doSort();

var_dump( $sort->objects );