3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arr = [[1]=>[[100]], [2]=>]; $ref = &$arr[1]; $ref[] = [101];
Output for 5.4.0 - 5.4.29
Parse error: syntax error, unexpected ']' in /in/F3aVn on line 3
Process exited with code 255.
Output for 5.3.0 - 5.3.28
Parse error: syntax error, unexpected '[' in /in/F3aVn on line 3
Process exited with code 255.

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180.21 ms | 1399 KiB | 66 Q