I (U+0049 LATIN CAPITAL LETTER I), * i (U+0069 LATIN SMALL LETTER I) -> İ (U+0130 LATIN CAPITAL LETTER I WITH DOT ABOVE). * * Unicode CaseFolding.txt defines these mappings as type 'T', which means that * they are only for the Turkic languages, tr and az. PHP ignores these mappings, * so we have to override the ucfirst and lcfirst methods. * * See https://en.wikipedia.org/wiki/Dotted_and_dotless_I and T30040 * * @ingroup Languages */ class LanguageTr extends Language { private const UC = [ 'I', 'İ' ]; private const LC = [ 'ı', 'i' ]; public function ucfirst( $str ) { $first = mb_substr( $str, 0, 1 ); if ( in_array( $first, self::LC ) ) { $first = str_replace( self::LC, self::UC, $first ); return $first . mb_substr( $str, 1 ); } return parent::ucfirst( $str ); } public function lcfirst( $str ) { $first = mb_substr( $str, 0, 1 ); if ( in_array( $first, self::UC ) ) { $first = str_replace( self::UC, self::LC, $first ); return $first . mb_substr( $str, 1 ); } return parent::lcfirst( $str ); } }