XMDP for class="defined"

The current HTML 5 draft specifies this algorithm for associating defined terms with their defining instances:

Any span, abbr, code, var, samp, or i element that has a non-empty title attribute whose value exactly equals the term of a dfn element in the same document, or which has no title attribute but whose textContent exactly equals the term of a dfn element in the document, and that has no interactive elements or dfn elements either as ancestors or descendants, and has no other elements as ancestors that are themselves matching these conditions, should be presented in such a way that the user can jump from the element to the first dfn element giving the defining instance of that term.

As browser implementations don’t currently implement such functionality, I thought it would be useful to define the class defined to provide analogous functionality. See this blog post for more.

The key words “MUST”, “MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”, “RECOMMENDED”, “MAY”, and “OPTIONAL” in this document are to be interpreted as described in RFC 2119.

class

HTML4 definition of the class attribute. This meta data profile defines some class attribute values (class names) and their meanings as suggested by a draft of "Hypertext Links in HTML".

defined

This element contains a term which is defined elsewhere in the document.

The term must be extracted from this element per the HTML 5 definition/term-association algorithm: if the element has a non-empty title attribute, then its value is the term defined elsewhere. If the element lacks a title attribute, the element’s textContent is the term. In either case, there must be a dfn element in the document whose term is the same as this element. The first such dfn is the defining instance of the term.

This work is in the public domain.