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run code in 300+ PHP versions simultaneously
<?php $d = ['old']; $c = &$d[0]; $d = ['new']; $d[0] = 2; var_dump($c);
Output for 7.1.25 - 7.1.28, 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 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
string(3) "old"
preferences:
108.64 ms | 1408 KiB | 4 Q