[DFDL-WG] whitespace in DFDL annotations: right now regex is xs:string, expression is xs:token

This came up on the call. The schemas I have for DFDL annotations have DFDLRegularExpression as an xs:string, and DFDLExpression as an xs:token. I have no clue what a union of these types behaves like. But we have a union called DFDLExpressionOrPatternOrNothing which is a 3-way union of DFDLExpression, DFDLRegularExpression, and EmptyString (which is also derived from xs:string but has length facet of 0 as well. -- Mike Beckerle | OGF DFDL Workgroup Co-Chair | Tresys Technology | www.tresys.com