[whatwg] WA1: rev attribute

[Matthew Raymond]

fantasai wrote:
> The 'rev' attribute from prior versions of HTML is missing in WA1,
> and I think it deserves not to be left out.

   I don't. It's almost entirely useless, and no one really uses it anyways.

> Most common link types
> out there are used with 'rel', but some 'rev' values can also be
> useful. Here are some use cases:
>    - rev="footnote" for a link back from the footnote or endnote to
>      the source anchor in the main text
>    - rev="help" for a link to the part of the site that the help
>      text is about

   This is largely useless, as you are unlikely to start at a
help/footnote document and go to the document for which the help
document was written. The most common situation is that you clicked the
help/footnote like from the parent document, and therefore the
relationship is already established from the parent document.

>    - rev="author" on a personal site or resume for links to documents
>      s/he has written

   Here, you're using |rev| to replace missing metadata in the target
document. What happens when <meta name="Author"> is defined in the
target documents? Does |rev| override? What would a UA do with the
information anyway? If there's a link, wouldn't there be text stating
that the creator of the personal site created the document the link is to?

> See also http://www.eastgate.com/HypertextNow/archives/Trigg.html
> for a direction link types could go in which 'rev' would be useful.

   Well, I scanned over it, and I noticed one good point. People often
don't bother putting in relationship types for links. Therefore, |rev|
could establish what the relationship is when you reach the target
document. The problem is that the argument is mostly self-defeating. If
people fail to use |rel|, how is a reverse version of that same
attribute going to be used with any frequency.

   At least with |rel|, you could harvest hyperlinks and put them into a
link toolbar. With |rev|, you're describing the relationship type of the
current document. Therefore, I really don't see what user agents are
supposed to do with |rev| and how they can create a useful interface
that can exploit this attribute.

> Many of the link types suggested there would be easier to use with
> rev for the reverse link than with a separate keyword that means
> the inverse relationship.
> Example:
>    rev="refutation" to link to the article one is refuting

Counterexample:
| <meta name="refuting" content="
|  Intelligent Design;
|  http://hemadeyou.org
| ">

   True, from a pure language standpoint, |rev| is more convenient.
However, if the author makes the hyperlink text "Click here!", and the
link is broken, what does the user agent have left to work with? The
same kind of abuse is not likely to happen with <meta>.