3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php var_dump( mb_substr('some string' , 2, null) );
Output for 5.4.8 - 5.6.28, hhvm-3.10.0 - 3.12.0, 7.0.0 - 7.1.0
string(9) "me string"
Output for 4.3.0 - 5.4.7
string(0) ""