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run code in 300+ PHP versions simultaneously
<?php $o = new stdClass; $id = -99; $a = array('id' => $id, 'name' => 'bill'); $o->$id = $a; var_export($o);
Output for 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
(object) array( '-99' => array ( 'id' => -99, 'name' => 'bill', ), )
Output for 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33
stdClass::__set_state(array( '-99' => array ( 'id' => -99, 'name' => 'bill', ), ))
Output for 5.0.0 - 5.0.5
class stdClass { public $-99 = array ( 'id' => -99, 'name' => 'bill', ); }
Output for 4.3.3 - 4.3.11, 4.4.0 - 4.4.9
class stdClass { }
Output for 4.3.0 - 4.3.2
class stdClass { var $-99 = array ( 'id' => -99, 'name' => 'bill', ); }

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285.64 ms | 401 KiB | 460 Q