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run code in 200+ PHP versions simultaneously
<?php $string = 'İyi akşamlar'; $upper = mb_strtoupper($string); $lowerChars = mb_strtolower(mb_substr($string, 0, 3)); var_dump($string, $upper, $lowerChars); var_dump(grapheme_stripos($upper, $lowerChars));
based on e5oNi
Output for 7.3.0 - 7.4.6
string(14) "İyi akşamlar" string(14) "İYI AKŞAMLAR" string(5) "i̇yi" int(0)
Output for 7.1.25 - 7.2.19
string(14) "İyi akşamlar" string(14) "İYI AKŞAMLAR" string(3) "iyi" bool(false)