3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = ""; $a[] = "y"; var_dump($a); $b = "x"; $b[] = "y"; var_dump($b);
Output for 7.1.0 - 7.1.25, 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.28, 8.4.1 - 8.4.14, 8.5.0
Fatal error: Uncaught Error: [] operator not supported for strings in /in/vg7Oe:2 Stack trace: #0 {main} thrown in /in/vg7Oe on line 2
Process exited with code 255.
Output for 8.4.15
/bin/php-8.4.15: /usr/lib/libm.so.6: version `GLIBC_2.38' not found (required by /bin/php-8.4.15) /bin/php-8.4.15: /usr/lib/libm.so.6: version `GLIBC_2.35' not found (required by /bin/php-8.4.15) /bin/php-8.4.15: /usr/lib/libc.so.6: version `GLIBC_2.34' not found (required by /bin/php-8.4.15) /bin/php-8.4.15: /usr/lib/libc.so.6: version `GLIBC_2.38' not found (required by /bin/php-8.4.15)
Process exited with code 1.
Output for 7.0.0 - 7.0.20
array(1) { [0]=> string(1) "y" } Fatal error: Uncaught Error: [] operator not supported for strings in /in/vg7Oe:3 Stack trace: #0 {main} thrown in /in/vg7Oe on line 3
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, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28
array(1) { [0]=> string(1) "y" } Fatal error: [] operator not supported for strings in /in/vg7Oe on line 3
Process exited with code 255.
Output for 4.3.0 - 4.3.1
array(1) { [0]=> string(1) "y" } Fatal error: [] operator not supported for strings in /in/vg7Oe on line 3

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