run code in 300+ PHP versions simultaneously
<?php $a="a / b"; $a=preg_replace('/\//','\\',$a); echo "First version: {$a}\n"; $a=preg_replace('/\//','\\\\',$a); echo "Second version: {$a}\n"; ?>

Shows result from various feature-branches currently under review from the php developers. Contact me to have additional branches featured.

Output for branch master
First version: a \ b Second version: a \ b

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