3v4l.org

run code in 300+ PHP versions simultaneously
<?php $string = "You may organize to find or seek a neighbor or a pastor in a harbor or orchard."; echo preg_replace('~(?<!\bor) (?!or\b)~', '_', $string);
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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
You_may_organize_to_find or seek_a_neighbor or a_pastor_in_a_harbor or orchard.
preferences:
145.17 ms | 407 KiB | 5 Q