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run code in 300+ PHP versions simultaneously
<?php function foo() { echo __FUNCTION__, "\n"; return 'key'; } echo "??=\n"; $array = []; $array[foo()] ??= 'default'; echo "\nrough equivalent\n"; $array = []; if (!isset($array[foo()])) { $array[foo()] = 'default'; }
Output for 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
??= foo rough equivalent foo foo
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 ??= foo rough equivalent foo foo
Output for 7.3.0 - 7.3.33
Parse error: syntax error, unexpected '=' in /in/ITSK6 on line 10
Process exited with code 255.
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135.12 ms | 401 KiB | 150 Q