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<?php class Widget implements Serializable { public $references = array(); public function serialize() { $vars = get_object_vars($this); $serialized = serialize($vars); return $serialized; } public function unserialize($serialized) { $array = unserialize($serialized); foreach($array as $k => $v) $this->$k = $v; } } class Placeholder { public $id; public function __construct($id) { $this->id = $id; } } unserialize('a:4:{i:0;C:6:"Widget":70:{a:1:{s:10:"references";a:1:{i:0;O:11:"Placeholder":1:{s:2:"id";i:1;}}}}i:1;C:6:"Widget":70:{a:1:{s:10:"references";a:1:{i:0;O:11:"Placeholder":1:{s:2:"id";i:2;}}}}i:2;C:6:"Widget":70:{a:1:{s:10:"references";a:1:{i:0;O:11:"Placeholder":1:{s:2:"id";i:1;}}}}i:3;C:6:"Widget":70:{a:1:{s:10:"references";a:1:{i:0;O:11:"Placeholder":1:{s:2:"id";i:1;}}}}}');

preferences:
29.2 ms | 402 KiB | 5 Q