3v4l.org

run code in 300+ PHP versions simultaneously
<?php $data = array('key' => null); var_dump(isset($data['key'])); var_dump(array_key_exists($data, 'key')); var_dump(isset($data['key']) && $data['key']);
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
bool(false) Fatal error: Uncaught TypeError: array_key_exists(): Argument #2 ($array) must be of type array, string given in /in/q3qHM:5 Stack trace: #0 {main} thrown in /in/q3qHM on line 5
Process exited with code 255.
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 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
bool(false) Warning: array_key_exists() expects parameter 2 to be array, string given in /in/q3qHM on line 5 NULL bool(false)
Output for 4.3.2 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17
bool(false) Warning: array_key_exists(): The second argument should be either an array or an object in /in/q3qHM on line 5 bool(false) bool(false)
Output for 4.3.0 - 4.3.1
bool(false) Warning: array_key_exists() [http://www.php.net/function.array-key-exists]: The second argument should be either an array or an object in /in/q3qHM on line 5 bool(false) bool(false)

preferences:
249.57 ms | 402 KiB | 340 Q