3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php class A {} $a = new A(); $b = new A(); $a->m = $b; $b->m = $a; var_dump(json_encode($a));
Output for 5.5.0 - 7.2.0
bool(false)
Output for 5.2.0 - 5.4.45
Warning: json_encode(): recursion detected in /in/hXiar on line 11 string(22) "{"m":{"m":{"m":null}}}"
Output for 5.0.0 - 5.1.6
Fatal error: Call to undefined function json_encode() in /in/hXiar on line 11
Process exited with code 255.
Output for 4.4.5 - 4.4.9
Fatal error: Call to undefined function: json_encode() in /in/hXiar on line 11
Process exited with code 255.
Output for 4.3.2 - 4.4.4
Fatal error: Call to undefined function: json_encode() in /in/hXiar on line 11
Process exited with code 255.
Output for 4.3.0 - 4.3.1
Fatal error: Call to undefined function: json_encode() in /in/hXiar on line 11