3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $foo = new ArrayObject(); $foo[] = $foo; var_dump(json_encode($foo));
based on OZJpe
Output for 5.5.0 - 5.6.28, hhvm-3.10.0 - 3.12.0, 7.0.0 - 7.1.0
bool(false)
Output for 5.2.0 - 5.4.45
Warning: json_encode(): recursion detected in /in/B11YU on line 5 string(16) "{"0":{"0":null}}"
Output for 5.0.0 - 5.1.6
Fatal error: Call to undefined function json_encode() in /in/B11YU on line 5
Process exited with code 255.
Output for 4.3.2 - 4.4.9
Fatal error: Cannot instantiate non-existent class: arrayobject in /in/B11YU 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/B11YU on line 3