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run code in 150+ php & hhvm versions
Bugs & Features
<?php $a = array(1, 2); $b = array(&$a); $a[] = $b; echo json_encode($a);
based on aJ9uH
Output for 5.5.0 - 7.1.0
Output for 5.2.0 - 5.4.45
Warning: json_encode(): recursion detected in /in/uOrCp on line 7 [1,2,[[1,2,null]]]
Output for 5.0.0 - 5.1.6
Fatal error: Call to undefined function json_encode() in /in/uOrCp on line 7
Process exited with code 255.
Output for 4.4.5 - 4.4.9
Fatal error: Call to undefined function: json_encode() in /in/uOrCp on line 7
Process exited with code 255.
Output for 4.3.2 - 4.4.4
Fatal error: Call to undefined function: json_encode() in /in/uOrCp on line 7
Process exited with code 255.
Output for 4.3.0 - 4.3.1
Fatal error: Call to undefined function: json_encode() in /in/uOrCp on line 7