Re: HTML Link Type Model

Joe English (joe@trystero.art.com)
Wed, 17 May 95 02:55:18 EDT

Roy T. Fielding <fielding@avron.ICS.UCI.EDU> wrote:
>
> At this point I'd like to throw a wet blanket on the link type
> discussion.

That's not a bad idea. I just have a couple
questions, then I'll shut up on the subject :-)

> [... earlier ...] All of Dave's examples in
> the HTML 3.0 spec are wrong. The SCO implementation is wrong.
> In fact, just about every single implementation of REL and REV that
> I know of is wrong, the exception being Lynx's use of REV="Made".

I don't see any discrepancy between

[ from the May 6 HTML I-D ]
| 8.1.4. REL
| The REL attribute gives the relationship(s) described by the
| hypertext link from the anchor to the target.

and using

<LINK REL=NEXT HREF="B">

in node "A" to mean that "B is the next node (after A)"
(as per Murray's document). Are you saying this is backwards?

+-----+ NEXT +-----+
| A |---------> | B |
+-----+ +-----+

I can't make my brain interpret this diagram to mean anything
other than "if you're at document A, B comes NEXT".
Maybe it's a left-to-right bias... How about:

<LINK REL=PARENT HREF="B">

+-----+ PARENT +-----+
| A |---------> | B |
+-----+ +-----+

To me this says

"A's parent is B"

(Murray's paper has the same interpretation.)
Are you saying that the WWW link model really
interprets this as

"A is the parent of B"

instead?

> [ ... much deleted ]
> For example, how many people can tell me the chapter number of A
> if it contains
>
> rel="next" href="chapter2.html" ?
> rev="prev" href="chapter2.html" ?
> rel="prev" href="chapter4.html" ?
>
> Now, I dare anyone to claim that an ordinary HTML author can use
> such an inherently confusing syntax with any degree of reliability!
> [...]
> RECOMMENDATION: Abandon this model. Declare REL and REV to be deprecated,
> and replace them with ROLE="" (defined in SGML as type NAMES)

Is this:

<link ROLE="next" href="xyzzy.html">

any less confusing than:

<link REL="next" href="xyzzy.html">

Ah, I see... "REL" labels the link, while "ROLE"
would label the *target* of the link. Correct?

Would it be possible to simply change the official
interpretation of the "REL" attribute to match
existing practice? (SCO's browser for one, and
I know of at least one document that makes heavy
use of <LINK> with relations defined as above.)

[...]
> But shouldn't they have an "X-" prefix, or something to indicate they
> are not well-known? OVER MY DEAD BODY!

"Me too". I never liked the X- convention...

--Joe English

joe@art.com