3v4l.org

run code in 500+ PHP versions simultaneously
<?php $input_lines="any word here related to #English must #be replaced."; $output = preg_replace("/(#\w+)/", "<a href='bla bla'>$1</a>", $input_lines); echo $output;
Output for 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.32, 8.3.0 - 8.3.33, 8.4.1 - 8.4.24, 8.5.0 - 8.5.9
any word here related to <a href='bla bla'>#English</a> must <a href='bla bla'>#be</a> replaced.

preferences:
92.97 ms | 1592 KiB | 4 Q