Example of credit card form, Bad Design: Expiration Date as a gYearMonth, do not use. The constraint transforms a gYearMonth to a date with string concatenation.. Required [element], Single Occurrence, with Simple Type [inline-CreditCard-NameOnCard] localName is [NameOnCard] without namespace Required [element], Single Occurrence, with Simple Type [inline-CreditCard-CardNumber] localName is [CardNumber] without namespace Required [element], Single Occurrence, with Simple Type [inline-CreditCard-ValidTo] localName is [ValidTo] without namespace Required [element], Single Occurrence, with Simple Type [inline-CreditCard-CVV] localName is [CVV] without namespace Example of credit card form, Bad Design: Expiration Date as a gYearMonth, do not use. The constraint transforms a gYearMonth to a date with string concatenation..