clarification of role attr

[TzviyaSiegman]

The role attribute is "to annotate markup languages with machine-extractable semantic information about the purpose of an element." (https://www.w3.org/TR/role-attribute/). This means that it provides specific information about the element to which it is applied. In the collections example

 <ol role="doc-index">

, this implies that the

is in fact the index. role="doc-index" should be applied to the index itself, not something that links to the index. The authors of the DPUB-ARIA spec might want to consider nesting doc-toc or allowing something akin to the EPUB 2 element with a title or label. Would this suffice?

[dauwhe]

I've removed role="doc-index" and added an inline issue. Thanks!

[dauwhe]

The rel attribute describes the "relationship between the document containing the hyperlink and the destination resource." Which makes me think about using dpub-aria role values in rel, as a way of describing the semantics of the destination.