3v4l.org

run code in 300+ PHP versions simultaneously
<?php $b = 123; $a = array('' => &$b, 'b' => 1, 'd' => 4, 'c' => 3); uasort($a, function($a, $b) { if ($a == $b) { return 0; } return ($a < $b) ? -1 : 1; }); var_dump($a);
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
array(4) { ["b"]=> int(1) ["c"]=> int(3) ["d"]=> int(4) [""]=> &int(123) }
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17
Parse error: syntax error, unexpected T_FUNCTION in /in/jBtO2 on line 5
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected T_FUNCTION in /in/jBtO2 on line 5
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/jBtO2 on line 5
Process exited with code 255.

preferences:
269.97 ms | 401 KiB | 380 Q