3v4l.org

run code in 300+ PHP versions simultaneously
<?php function func(&$arraykey) { return $arraykey; // function returns by value! } $array = array('a', 'b', 'c'); foreach (array_keys($array) as $key) { $y = &func($array[$key]); $z[] =& $y; } var_dump($z);
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.12 - 7.3.31, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Notice: Only variables should be assigned by reference in /in/XnVHZ on line 8 Notice: Only variables should be assigned by reference in /in/XnVHZ on line 8 Notice: Only variables should be assigned by reference in /in/XnVHZ on line 8 array(3) { [0]=> &string(1) "c" [1]=> &string(1) "c" [2]=> &string(1) "c" }
Output for 4.4.0 - 4.4.9, 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 7.3.32 - 7.3.33
array(3) { [0]=> &string(1) "c" [1]=> &string(1) "c" [2]=> &string(1) "c" }
Output for 5.5.0 - 5.5.35, 5.6.0 - 5.6.28
Strict Standards: Only variables should be assigned by reference in /in/XnVHZ on line 8 Strict Standards: Only variables should be assigned by reference in /in/XnVHZ on line 8 Strict Standards: Only variables should be assigned by reference in /in/XnVHZ on line 8 array(3) { [0]=> &string(1) "c" [1]=> &string(1) "c" [2]=> &string(1) "c" }
Output for 4.3.0 - 4.3.11, 5.0.0 - 5.0.4
array(3) { [0]=> &string(1) "a" [1]=> &string(1) "b" [2]=> &string(1) "c" }
preferences:
261.63 ms | 402 KiB | 345 Q