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run code in 200+ php & hhvm versions
Bugs & Features
<?php class A {} $a = new A(); $b = new A(); $a->m = $b; var_dump(serialize($a));
Output for 5.0.0 - 7.3.0rc4
string(32) "O:1:"A":1:{s:1:"m";O:1:"A":0:{}}"
Output for 4.3.0 - 4.4.9
string(32) "O:1:"a":1:{s:1:"m";O:1:"a":0:{}}"