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run code in 300+ PHP versions simultaneously
<?php $a = array(1, 2); $b = array(&$a); $a[] = $b; var_dump(json_encode($a, JSON_ERROR_SYNTAX)); echo json_last_error();
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.17 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
bool(false) 6
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45
Warning: json_encode(): recursion detected in /in/hoUaR on line 7 string(18) "[1,2,[[1,2,null]]]" 0
Output for 5.2.0 - 5.2.17
Notice: Use of undefined constant JSON_ERROR_SYNTAX - assumed 'JSON_ERROR_SYNTAX' in /in/hoUaR on line 7 Warning: json_encode() expects exactly 1 parameter, 2 given in /in/hoUaR on line 7 NULL Fatal error: Call to undefined function json_last_error() in /in/hoUaR on line 8
Process exited with code 255.
Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.6
Fatal error: Call to undefined function json_encode() in /in/hoUaR 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/hoUaR on line 7
Process exited with code 255.
Output for 4.3.2 - 4.3.11, 4.4.0 - 4.4.4
Fatal error: Call to undefined function: json_encode() in /in/hoUaR 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/hoUaR on line 7

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