--TEST-- SPL: SplObjectStorage: recursive var_dump --FILE-- <?php $o = new SplObjectStorage(); $o[new StdClass] = $o; var_dump($o); --EXPECTF-- object(SplObjectStorage)#%d (1) { ["storage":"SplObjectStorage":private]=> array(1) { ["%s"]=> array(2) { ["obj"]=> object(stdClass)#%d (0) { } ["inf"]=> *RECURSION* } } }