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run code in 300+ PHP versions simultaneously
<?php $a = ""; $a[] = "x"; var_dump($a); $a = "x"; $a[] = "y"; var_dump($a);
Output for 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Fatal error: Uncaught Error: [] operator not supported for strings in /in/oj9kc:4 Stack trace: #0 {main} thrown in /in/oj9kc on line 4
Process exited with code 255.
Output for 7.0.0 - 7.0.20
array(1) { [0]=> string(1) "x" } Fatal error: Uncaught Error: [] operator not supported for strings in /in/oj9kc:8 Stack trace: #0 {main} thrown in /in/oj9kc on line 8
Process exited with code 255.
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, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28
array(1) { [0]=> string(1) "x" } Fatal error: [] operator not supported for strings in /in/oj9kc on line 8
Process exited with code 255.
Output for 4.3.0 - 4.3.1
array(1) { [0]=> string(1) "x" } Fatal error: [] operator not supported for strings in /in/oj9kc on line 8

preferences:
221.43 ms | 401 KiB | 358 Q