3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $arr = [1=>"a",3=>'b']; $result = (string)json_encode($arr); echo $result; ?>
based on hEi3E
Output for 5.4.0 - 7.2.0
{"1":"a","3":"b"}
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.3.29
Parse error: syntax error, unexpected '[' in /in/K79Xs on line 3
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected '[' in /in/K79Xs on line 3
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/K79Xs on line 3
Process exited with code 255.