- spl_object_hash: documentation ( source)
<?php
$a = new \stdClass();
$b = new \stdClass();
$a->foo = 'bar';
$b->foo = 'bar';
$ah = spl_object_hash($a);
$bh = spl_object_hash($b);
echo $ah . PHP_EOL;
echo $bh . PHP_EOL;
echo $ah == $bh ? 'true' : 'false';