3v4l.org

run code in 300+ PHP versions simultaneously
<?php $original = [-7 => 'first', -6 => 'second']; $original[] = 'third'; print_r($original);
Output for 8.0.1 - 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
Array ( [-7] => first [-6] => second [-5] => third )
Output for 7.4.0 - 7.4.33
Array ( [-7] => first [-6] => second [0] => third )

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