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<?php function index() { $a = 2; $b = 8; $arr[] = $a; $arr[] = &$a; $arr[] = $a; dmp($arr); $arr[1] = $b; echo $a.PHP_EOL; dmp($arr); $a++; $b++; echo $a.PHP_EOL; dmp($arr); } function dmp($val) { echo '<pre>'; var_dump($val); echo '</pre>'; } index();
Output for 7.1.25 - 7.1.30, 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 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.7
<pre>array(3) { [0]=> int(2) [1]=> &int(2) [2]=> int(2) } </pre>8 <pre>array(3) { [0]=> int(2) [1]=> &int(8) [2]=> int(2) } </pre>9 <pre>array(3) { [0]=> int(2) [1]=> &int(9) [2]=> int(2) } </pre>

preferences:
135.31 ms | 403 KiB | 170 Q