3v4l.org

run code in 300+ PHP versions simultaneously
<?php $h = "asdasd __asdasd__ frer __ desg df -+ br __"; preg_match_all('/_\_(.*?)_\_/i', $h, $r); $rr = preg_replace('/_\_(.*?)_\_/i', '$$$', $h); print_r($r);
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.17 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Array ( [0] => Array ( [0] => __asdasd__ [1] => __ desg df -+ br __ ) [1] => Array ( [0] => asdasd [1] => desg df -+ br ) )

preferences:
300.95 ms | 406 KiB | 377 Q