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run code in 300+ PHP versions simultaneously
<?php $arr = [1 => 1, 3 => 3]; // [1 => 1, 2 => 3] will print both keys foreach($arr as $key => &$val) { // without & will print both keys echo "See key {$key}\n"; $arr[0] = 0; // without this line will print both keys unset($arr[0]); }
Output for 5.6.38, 7.0.33, 7.1.0 - 7.1.25, 7.2.11 - 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 - 8.3.4, 8.3.6
See key 1 See key 3
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 See key 1 See key 3
Output for 7.2.0 - 7.2.10
See key 1
preferences:
140.06 ms | 401 KiB | 179 Q