3v4l.org

run code in 300+ PHP versions simultaneously
<?php $phrase = "The key is now set to :key"; $key = ":key"; $var = "if > $1000"; $re = "/(.+?)(" . $key . ")(.*)/"; $subst = "\1'" . $var . "'\3"; echo preg_replace($re, $subst, $phrase);
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 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 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.7
'if > 00'
preferences:
241.24 ms | 404 KiB | 378 Q