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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 - 7.1.10, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.18, 8.3.0 - 8.3.4, 8.3.6
bool(false) int(4) 6
Output for 8.3.5
Warning: PHP Startup: Unable to load dynamic library 'sodium.so' (tried: /usr/lib/php/8.3.5/modules/sodium.so (libsodium.so.23: cannot open shared object file: No such file or directory), /usr/lib/php/8.3.5/modules/sodium.so.so (/usr/lib/php/8.3.5/modules/sodium.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0 bool(false) int(4) 6
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45
Warning: json_encode(): recursion detected in /in/htQWf on line 7 string(18) "[1,2,[[1,2,null]]]" int(4) 0
Output for 5.2.0 - 5.2.17
Warning: json_encode(): recursion detected in /in/htQWf on line 7 Notice: Use of undefined constant JSON_ERROR_SYNTAX - assumed 'JSON_ERROR_SYNTAX' in /in/htQWf on line 7 string(18) "[1,2,[[1,2,null]]]" string(17) "JSON_ERROR_SYNTAX" Fatal error: Call to undefined function json_last_error() in /in/htQWf 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/htQWf 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/htQWf 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/htQWf 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/htQWf on line 7

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