3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $not_allowed_symbols = '[^a-z0-9:;,!\'\s*.?()"-]'; //$letter = nl2br("aaa\nbbb\nccc"); //print_r($letter); if(preg_match("/$not_allowed_symbols/i", $letter)){ echo "There are not allowed symbols in the text"; }else{ echo "There are allowed symbols in the text"; }
Output for 5.0.4 - 7.1.0
Notice: Undefined variable: letter in /in/jV1h1 on line 5 There are allowed symbols in the text
Output for 4.3.0 - 5.0.3
Notice: Undefined variable: letter in /in/jV1h1 on line 5 There are allowed symbols in the text