It's not an ad-hoc restriction. It's because a complex element has no value, so there are no DFDL properties to describe a value.

Regards
 
Steve Hanson
Architect, IBM DFDL
Co-Chair, OGF DFDL Working Group
IBM SWG, Hursley, UK
smh@uk.ibm.com
tel:+44-1962-815848



From:        Mike Beckerle <mbeckerle.dfdl@gmail.com>
To:        "dfdl-wg@ogf.org" <dfdl-wg@ogf.org>
Date:        27/04/2015 19:06
Subject:        [DFDL-WG] complex nillable ES restriction
Sent by:        dfdl-wg-bounces@ogf.org

---

Right now complex elements can be nillable, but we have this ad-hoc restriction that says the nilValue can only be %ES;.

The rationale for this is unclear to me. Can we review what the rationale for this restriction was? Does anyone recall?

We have a format where the literal nil value for the complex type wants to be "%WSP*;-%WSP*;" that is, a hyphen, but with surrounding whitespace absorbed.

We can model this a different way, but the natural thing to do is to model it as suggested.

(This also just happens to run on Daffodil - because we're not detecting this ad-hoc restriction - a bug)

Mike Beckerle | OGF DFDL Workgroup Co-Chair | Tresys Technology | www.tresys.com
Please note: Contributions to the DFDL Workgroup's email discussions are subject to the OGF Intellectual Property Policy
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