3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php var_dump(mb_convert_case('asdf', MB_CASE_UPPER, ''));
based on CLvHm
Output for 5.2.6 - 7.2.0
Warning: mb_convert_case(): Unknown encoding "" in /in/dktGi on line 3 bool(false)
Output for 4.3.2 - 5.2.5
Warning: mb_convert_case(): Illegal character encoding specified in /in/dktGi on line 3 string(4) "ASDF"
Output for 4.3.0 - 4.3.1
Warning: mb_convert_case() [http://www.php.net/function.mb-convert-case]: Illegal character encoding specified in /in/dktGi on line 3 string(4) "ASDF"