::class feature of PHP 5.5

test-class-loading.php

<?php
namespace Baz;
use Bar\Foo;
define('LF', chr(10));
spl_autoload_register(function($className){
	echo 'trying to load class: ' . $className . LF;
});

echo LF . 'starting ...' . LF;
$a = Foo::class;
echo 'class name calculated: ' . $a . LF;

class_exists($a);

echo 'finished!' . LF . LF;