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 -- dfdl-wg mailing list dfdl-wg@ogf.org https://www.ogf.org/mailman/listinfo/dfdl-wg Unless stated otherwise above: IBM United Kingdom Limited - Registered in England and Wales with number 741598. Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6 3AU