Hi all,

I know this area of the specification was only recently resolved, and I think there may be an inconsistency in the v0.37 wording.

Section 16, re: sequenceKind says: "The children of an unordered sequence must be xs:element."
Section 16.5 Floating Elements says: "An ordered sequence of n element children with either n or n-1 of those children with dfdl:floating="true" is equivalent to an unordered sequence with the same n element children with dfdl:floating="false". A complex element with dfdl:floating="true" can have as its content model a sequence with elements that also have dfdl:floating="true". "

Now suppose that, instead of N element children, there are N-1 floating element children + one non-floating group. This group will be equivalent to an unordered group with a non-element member.
If the specification was intending to make life easy for implementers, then it should probably disallow groups in any non-ordered context, including when sequenceKind='ordered' and there is at least one floating component. But I think that would be too restrictive. I would be happy for the restriction to be lifted entirely. Given that unordered groups can have dfdl:initiated="false", it will sometimes be necessary to find the correct member by trial and error ( speculative parsing ) anyway. I don't think it's any more difficult to speculatively parse a group than to speculatively parse a complex element.

If I've missed something, and it turns out that the restriction is useful, then we should
a) tighten up the wording to say that if a group with N members has N or N-1 floating members, then it must be validated as if it was an unordered group.
b) consider lifting the restriction in cases where dfdl:initiated="true" ( because it makes things so much easier for the DFDL processor )

regards,

Tim Kimber, Common Transformation Team,
Hursley, UK
Internet:  kimbert@uk.ibm.com
Tel. 01962-816742  
Internal tel. 246742



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