3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $arr = [1 => 1, 3 => 3]; // [1 => 1, 2 => 3] will print both keys foreach($arr as $key => &$val) { // without & will print both keys echo "See key {$key}\n"; $arr[0] = 0; // without this line will print both keys unset($arr[0]); }
Output for 5.4.0 - 5.6.38, hhvm-3.10.1 - 3.22.0, 7.0.0 - 7.1.25, 7.2.11 - 7.3.0
See key 1 See key 3
Output for 7.2.0 - 7.2.10
See key 1
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.3.29
Parse error: syntax error, unexpected '[' in /in/8Oi0k 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/8Oi0k on line 3
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/8Oi0k on line 3
Process exited with code 255.