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run code in 300+ PHP versions simultaneously
<?php var_dump(isset($a)); $a = null; var_dump(isset($a));
Output for 7.1.0 - 7.1.33, 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 - 8.1.30, 8.2.0 - 8.2.26, 8.3.0 - 8.3.14, 8.4.1
bool(false) bool(false)
preferences:
82.25 ms | 407 KiB | 5 Q