3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $null = NULL; $empty = ''; $start=microtime(TRUE); for($i=0;$i<1000000000;$i++) { if($empty === '') { } } var_export(microtime(TRUE)-$start); echo "\n"; $start=microtime(TRUE); for($i=0;$i<1000000000;$i++) { if(!isset($null)) { } } var_export(microtime(TRUE)-$start); echo "\n";
Output for 5.3.7 - 7.1.0

Process exited with code 137.