3v4l.org

run code in 300+ PHP versions simultaneously
<?php function func(&$data) { foreach ($data as $key => $value) { if (is_array($value)) { func($data[$key]); } } } $data = [ ['k' => [0]], ['k' => [1]], ]; ob_start(); debug_zval_dump($data[1]['k']); echo explode("\n", ob_get_clean())[0]."\n"; // refcount(2) func($data); ob_start(); debug_zval_dump($data[1]['k']); echo explode("\n", ob_get_clean())[0]."\n"; // refcount(3) array_replace_recursive($data[0], $data[1]); echo json_encode($data);
Output for 8.4.1 - 8.4.2
array(1) packed refcount(2){ array(1) packed refcount(3){ [{"k":[0]},{"k":[1]}]
Output for 7.0.6 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.31, 8.2.0 - 8.2.26, 8.3.0 - 8.3.15
array(1) refcount(2){ array(1) refcount(3){ [{"k":[0]},{"k":[1]}]
Output for 7.0.0 - 7.0.5
array(1) refcount(2){ array(1) refcount(3){ [{"k":[1]},{"k":[1]}]
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.40
array(1) refcount(2){ array(1) refcount(2){ [{"k":[0]},{"k":[1]}]
preferences:
38.67 ms | 409 KiB | 5 Q