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<?php $value = str_repeat('a.', 126) . 'aaaa'; // 256 characters, max allowed is 253, trailing dot ignored $result = idn_to_ascii($value, 0, INTL_IDNA_VARIANT_UTS46, $idnaInfo); var_dump($result); var_dump($idnaInfo); // $idnaInfo['errors'] should be equal to 4, it is value of IDNA_ERROR_DOMAIN_NAME_TOO_LONG

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