3v4l.org

run code in 300+ PHP versions simultaneously
<?php $foo = new ArrayObject(); $foo[] = new ArrayObject(); var_dump(json_encode($foo));
Output for 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, 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, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
string(8) "{"0":{}}"
Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.6
Fatal error: Call to undefined function json_encode() in /in/f4J2T on line 5
Process exited with code 255.
Output for 4.3.2 - 4.3.11, 4.4.0 - 4.4.9
Fatal error: Cannot instantiate non-existent class: arrayobject in /in/f4J2T on line 3
Process exited with code 255.
Output for 4.3.0 - 4.3.1
Fatal error: Cannot instantiate non-existent class: arrayobject in /in/f4J2T on line 3

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252.41 ms | 401 KiB | 389 Q