[whatwg] Microdata feedback: please state that property value ordering is in the data model, and give usage guidelines

[Dan Brickley]

Hello,

Reading http://www.whatwg.org/specs/web-apps/current-work/multipage/links.html#microdata

Section '5.2.3 Names: the itemprop attribute' states something
important about Microdata's data model,

"Within an item, the properties are unordered with respect to each
other, except for properties with the same name, which are ordered in
the order they are given by the algorithm that defines the properties
of an item."

... and gives an example "In the following example, the "a" property
has the values "1" and "2", in that order,  ...
<div itemscope itemref="x">
 <p itemprop="b">test</p>
 <p itemprop="a">2</p>
</div>
<div id="x">
 <p itemprop="a">1</p>
</div>"

However '5.2.1 The microdata model' does not mention anything of this
data model feature. If property values (for some specific
property/item context), this should be mentioned when introducing the
data model; if only by copying or linking the above sentence ("Within
an item, ...").

Is the expectation that Microdata vocabulary authors can decide
whether such ordering is meaningful, when they define / describe their
properties?

For example, in academic publishing where they care about being first
named author, the ordering of 'itemprop="author"' might seem to
matter. 5.2.3 suggests that the ordering information is at least
preserved in Microdata's data model. If someone creates an 'author'
property for Microdata, should they state that property ordering is
meaningful, or is that not their decision?

Thanks,

Dan