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run code in 300+ PHP versions simultaneously
<?php $in = array(); for($i = 1; $i <=5; $i++) { $in[] = i; } $res = array();// Array where we will write result $t = &$res; // Link to first level foreach ($in as $k) { // Walk through source array if (empty($t[$k])) { // Check if current level has required key $t[$k] = array(); // If does not, create empty array there $t = &$t[$k]; // And link to it now. So each time it is link to deepest level. } } unset($t); // Drop link to last (most deep) level var_dump($res);
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.4, 8.3.6
Fatal error: Uncaught Error: Undefined constant "i" in /in/eg4cn:6 Stack trace: #0 {main} thrown in /in/eg4cn on line 6
Process exited with code 255.
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 Fatal error: Uncaught Error: Undefined constant "i" in /in/eg4cn:6 Stack trace: #0 {main} thrown in /in/eg4cn on line 6
Process exited with code 255.
Output for 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
Warning: Use of undefined constant i - assumed 'i' (this will throw an Error in a future version of PHP) in /in/eg4cn on line 6 Warning: Use of undefined constant i - assumed 'i' (this will throw an Error in a future version of PHP) in /in/eg4cn on line 6 Warning: Use of undefined constant i - assumed 'i' (this will throw an Error in a future version of PHP) in /in/eg4cn on line 6 Warning: Use of undefined constant i - assumed 'i' (this will throw an Error in a future version of PHP) in /in/eg4cn on line 6 Warning: Use of undefined constant i - assumed 'i' (this will throw an Error in a future version of PHP) in /in/eg4cn on line 6 array(1) { ["i"]=> array(1) { ["i"]=> array(1) { ["i"]=> array(1) { ["i"]=> array(1) { ["i"]=> array(0) { } } } } } }

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