Question: Is an assertion using a regular expression pattern allowed on (a) xs:string type elements (b) any data with text representation (c) any data with text or binary representation and, does the regular expression apply to the representation or the logical data value? (a) is the only case that is not ambiguous, because the representation and the logical value are the same thing. For everything else, there’s the question of whether the test is on the representation or the logical value. If it's the logical value, then how is a regex made meaningful on a logical value that is, for example, a number, without defining a canonical representation to which the logical value is converted? If it's to apply to the representation, then exactly what data? (Eg., what grammar region) is subject to the regex? ...mikeb -- Mike Beckerle | OGF DFDL WG Co-Chair Tel: 781-330-0412