/** * Will return the 'Return-Receipt-To:', e-mail HEADER, which will allow sent emails to be returned to a specific email, * which can be checked to be sure that users that have signed-up with our mechanisms are still alive, and working ... * * @param S $objReceiptTo */ public function setReadReceipt(S $objReceiptTo) { self::$objReceiptTo = _S(self::MAIL_HEADER_RETURN_RECEIPT_TO . _N_ . self::MAIL_HEADER_NOTIFICATION_TO . _N_)->doToken('%s', $objReceiptTo); }