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<?php define('KINT_MB', function_exists('mb_substr')); $time = microtime(true) * 1000; for ($i = 0; $i < 1000; $i++) { if (function_exists('mb_substr')) { } } $time1 = microtime(true) * 1000; for ($i = 0; $i < 1000; $i++) { if (KINT_MB) { } } $time2 = microtime(true) * 1000; var_dump(round($time1 - $time)); var_dump(round($time2 - $time1)); var_dump([$time, $time1, $time2]);

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28.98 ms | 402 KiB | 5 Q