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run code in 300+ PHP versions simultaneously
<?php $array = []; $array['a'] =& $array['b']; $array['b'] = 1; var_dump($array);
Output for 5.6.0 - 5.6.26, 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
array(2) { ["b"]=> &int(1) ["a"]=> &int(1) }
Output for 7.0.0 - 7.0.20
array(2) { ["a"]=> &int(1) ["b"]=> &int(1) }
preferences:
104.62 ms | 407 KiB | 5 Q