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<?php class kissa implements Serializable { private $foo = 8; public $bar = 'kissa'; protected $baz = []; public function serialize() { return json_encode( get_class_vars( self::class ) ); } public function unserialize( $s ) {} } var_dump( serialize(new kissa()) );

preferences:
73.31 ms | 402 KiB | 5 Q