David Powell wrote:
Section 6.4:
The RNGs in this section require Extension Elements to be in a
namespace that isn't the Atom namespace. This requirement is missing
from the text.
It's actually worse than just that.
Section 6.1 defines "foreign markup" as being "markup from other
vocabularies". WRT section 6.2 describing "extensions to the Atom
vocabulary", I understand this definition of "foreign markup" as "markup
in a namespace different from the Atom one.
Section 6.4 *implies* Extension Elements are foreign markup as the first
sentence of that section is "Atom allows foreign markup anywhere in an
Atom document" though it's not explicit at all.
Having re-read the draft without looking at the RNC excerpts, the whole
section 6 with its subsections are totally unclear about what is
"foreign markup" (or what is behind "Atom vocabulary"), what are
"extensions", what are Simple/Structured Extension Elements and how they
relate to foreign markup.
Even more, I'm wondering why would there be a need to define
Simple/Structured Extension Elements in terms of "constraints". I
suppose that it's a way to distinguish extensions in the form
text-only from extensions using attributes
and/or child elements; and such a distinction is only necessary because
we want to provide a hint about how to interpret extensions in the
former form (no attribute, text-only content).
Wouldn't it be clearer (less obscure) to anyone dropping section 6.4 and
just saying something like the following:
Elements from foreign markup with no attribute and text-only content
MAY be interpreted by an Atom Processor as a property (or name/value
pair) of the parent element that encloses it. This specification
does not provide an interpretation for other elements.
Still about extensions, have I missed something or nowhere the spec
allows for "extension attributes" (I mean namespaced attributes
appearing on Atom elements)? I suggest such attributes to be interpreted
as a property (or name/value pair) of the element on which it appears.
Finally, in section 6.2, in the last sentence, "for the purpose of this
discussion" applies only to the section 6.3 about how to process them:
they obviously aren't "extensions", are they? I suggest moving this
sentence into section 6.3.
There might be other things I missed this evening...
--
Thomas Broyer
