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run code in 300+ PHP versions simultaneously
<?php error_reporting(0); $undef; $undef2 = null; $undef3 = null; unset($undef3); echo '$undef === $undef2?'; var_dump($undef === $undef2); echo '$undef === $undef3?'; var_dump($unedf === $undef3); echo '$undef2 === $undef3?'; var_dump($undef2 === $undef3); get_defined_vars();
Output for 5.4.2 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
$undef === $undef2?bool(true) $undef === $undef3?bool(true) $undef2 === $undef3?bool(true)
preferences:
199.12 ms | 404 KiB | 225 Q