On the call last week, it was agreed that a conservative approach to pattern based lengths was sufficient for DFDL 1.0.  Revised text for 12.3.5.1:

12.3.5.1         Pattern-Based Lengths  - Scanability

dfdl:lengthKind 'pattern' may be specified for
·        elements of simple type with representation 'text'
·        elements of complex type

For an element of complex type:
  1. all simple child elements must have representation 'text' and have the same encoding as the parent complex element, and
  2. all complex child elements must themselves follow 1 and 2 (recursively).

Similar wording to apply to dfdl:assert testKind="pattern".

Regards

Steve Hanson
Architect, Data Format Description Language (DFDL)
Co-Chair, OGF DFDL Working Group
IBM SWG, Hursley, UK
smh@uk.ibm.com
tel:+44-1962-815848





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