3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $txt = <<<TXT jkDDDJJJJjjjjJJlk jhlkj_sdHHhhHhhHHHHHHH kjhlkjh_JJJjjkkkkIIIIiiii TXT; echo preg_replace('/(.)(.*)/', "\u\\1\L\\2\E", $txt);
Output for 4.3.0 - 7.1.10
\uj\LkDDDJJJJjjjjJJlk\E \uj\Lhlkj_sdHHhhHhhHHHHHHH\E \uk\Ljhlkjh_JJJjjkkkkIIIIiiii\E