3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = array(0 => 100, "color" => "red"); print_r(array_keys($array)[1]);
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.31, 8.2.0 - 8.2.26, 8.3.0 - 8.3.14, 8.4.1
color
Output for 5.3.0 - 5.3.29
Parse error: syntax error, unexpected '[' in /in/TrOGV on line 4
Process exited with code 255.
preferences:
80.86 ms | 406 KiB | 5 Q