3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = array('key' => 'bla'); echo $array[key]; echo $array['key'];
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Fatal error: Uncaught Error: Undefined constant "key" in /in/YBQP0:5 Stack trace: #0 {main} thrown in /in/YBQP0 on line 5
Process exited with code 255.
Output for 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
Warning: Use of undefined constant key - assumed 'key' (this will throw an Error in a future version of PHP) in /in/YBQP0 on line 5 blabla
Output for 4.3.0 - 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, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.38, 7.0.0 - 7.0.33, 7.1.0 - 7.1.25
Notice: Use of undefined constant key - assumed 'key' in /in/YBQP0 on line 5 blabla

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257.59 ms | 404 KiB | 421 Q