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.


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Mike Beckerle | OGF DFDL Workgroup Co-Chair | Tresys Technology | www.tresys.com