document #334
Updated by Michael Beckerle over 4 years ago
DFDL disallows certain XSD constructs for modeling data. For example attribute declarations are not used.
However DFDL should co-exist in schemas along with other annotation languages. Those annotation languages may (just like DFDL) want to use attributes on their annotation elements.
To enable annotation languages. DFDL should look at the xs:schema element for a xmlns binding of the DFDL namespace. If there is no such binding, then the DFDL processor should skip that schema file - that is, not import/include it for purposes of parsing/unparsing.
The imported schema may still be imported for purposes of validating the annotation language it describes.