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<?php function get_refcount($v) { ob_start(); debug_zval_dump($v); $m = null; preg_match('@refcount\(\d+\)@', ob_get_clean(), $m); return $m[0]; } function func(&$data) { foreach ($data as $key => $value) { if (is_array($value)) { func($data[$key]); } } } $data = [ ['k' => [0]], ['k' => [1]], ]; echo get_refcount($data[1]['k'])."\n"; //refcount(2) func($data); echo get_refcount($data[1]['k'])."\n"; //refcount(3) array_replace_recursive($data[0], $data[1]); echo json_encode($data);
Output for 7.0.6 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
refcount(3) refcount(4) [{"k":[0]},{"k":[1]}]
Output for 7.0.0 - 7.0.5
refcount(3) refcount(4) [{"k":[1]},{"k":[1]}]
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.28
refcount(4) refcount(4) [{"k":[0]},{"k":[1]}]

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