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run code in 300+ PHP versions simultaneously
<?php var_dump(setlocale(LC_ALL, 'de_DE.ISO-8859-1')); echo bin2hex(str_ireplace(["\xE4", "\xF6", "\xFC"], ['1', '2', '3'], "\xE4\xC4 \xF6\xD6 \xFC\xDC")) . PHP_EOL;
based on 5mbCX
Output for 7.3.23, 7.4.11 - 7.4.12, 8.0.0
string(16) "de_DE.ISO-8859-1" 3131203232203333
Output for 7.2.0 - 7.2.33, 7.3.0 - 7.3.21, 7.4.0 - 7.4.10
string(16) "de_DE.ISO-8859-1" e4c420f6d620fcdc