3v4l.org

run code in 300+ PHP versions simultaneously
<?php $s = 'string'; $a = []; $a['foo'] =& $s; var_dump($a); $a = []; $a['foo'] = $s; var_dump($a);
Output for 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.26, 8.1.0 - 8.1.13
array(1) { ["foo"]=> &string(6) "string" } array(1) { ["foo"]=> string(6) "string" }

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62.39 ms | 409 KiB | 5 Q