3v4l.org

run code in 300+ PHP versions simultaneously
<?php $string = 'aaAAąAŚĆżź'; echo preg_replace_callback( '/(\p{Lu})|(\p{Ll})/u', function($m) { return $m[1] ? mb_strtolower($m[1]) : mb_strtoupper($m[2]); }, $string );
Output for git.master, git.master_jit, rfc.property-hooks
AAaaĄaśćŻŹ

This tab shows result from various feature-branches currently under review by the php developers. Contact me to have additional branches featured.

Active branches

Archived branches

Once feature-branches are merged or declined, they are no longer available. Their functionality (when merged) can be viewed from the main output page

preferences:
67.76 ms | 401 KiB | 8 Q