3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $_content = '$1$2'; preg_match('#(.*)#',$_content, $matches); $_content = preg_replace('#(?:.*)#', '<span name="iframe_stretch">$0</span>', $_content); echo $_content; var_dump($matches);
based on gR9Dr
Output for 4.3.0 - 7.1.0
<span name="iframe_stretch">$1$2</span><span name="iframe_stretch"></span>array(2) { [0]=> string(4) "$1$2" [1]=> string(4) "$1$2" }