Introduction: The Value Element Problem
Adding attribute support to dfdl (as proposed here: Proposal: Extend DFDL with XML Attribute Support) will be a step in the right direction, but does not solve the general problem of starting from a logical XML schema that you like, and then matching it up against data with properties.
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which is still unnatural and inefficient.
Solution: Properties for Complex Representation for Simple Types - The dfdlx:repType Property
A mechanism where a simple type element (or attribute someday) can get its value from a hidden complex structure, is needed.
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Note that there is already a dfdlx:repType property used to enable numeric simple type values to be converted to string values from an enum type. (See: Proposal: (Superceded) Feature to support enumerations and typeValueCalc)
This usage would not conflict with that, because in this case the representation type is a complex type.
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