- From: Ben Adida <ben@adida.net>
- Date: Fri, 01 Jun 2007 08:25:10 -0700
- To: mark.birbeck@x-port.net
- CC: Dan Brickley <danbri@danbri.org>, Elias Torres <elias@torrez.us>, RDFa <public-rdf-in-xhtml-tf@w3.org>
In case Mark's email was still too long for Elias's spinning head... :) There was consensus on the call yesterday that we cannot make RDFa a moving target anymore. There may be small additions (like @resource), but all currently written RDFa is going to keep working, and the additions will be minimal. The discussion around these last small tweaks may be a bit involved, as this is the last stretch, but the result will be simple. Hope this helps calm fears! -Ben Mark Birbeck wrote: > > > I'm sorry that this is your perception because the threads are > actually about *resolving* issues! Maybe the posts are too long to be > read thoroughly ;) and it just _looks_ like it's all change. > > Anyway, I'll recap for you, and then you can tell me whether you are > still concerned..... > > > @HREF EVERYWHERE > > The context for all of this is '@href everywhere'; we've had this in > RDFa for a few years now, but recently the objection has been raised > that some authors might get confused, and think that mark-up like this > represents a clickable link: > > <span rel="a" href="b">hello</span> > > There are some who disagree with that view (myself, Steven, Shane) and > there are those who think this is something that could affect the > adoption of RDFa (Ivan, Ben). > > Speaking only for myself, I don't see it being crucial to the adoption > of RDFa, since that seems to be picking up speed nicely already. And I > also don't see it as being confusing for authors, since: > > * authors are already doing it; > > * authors new to RDFa are unlikely to actually use or see this > construct, since > they will usually be dealing with 'clickable links'. > > But what the heck...I'm really not that bothered about it, and we need > to resolve all disagreements somehow. But the problem with finding a > resolution is that the only justification I've seen for this change to > @href is that 'authors _might_ find it confusing', and when things are > expressed only as a matter of opinion, we unfortunately will often > reach an impasse. > > > BRING BACK @RESOURCE > > So I decided to devote some time to finding a resolution, and it > turned out that a simple solution was available--to resurrect the > @resource attribute which was in the original drafts of RDFa. But this > time, we'd keep our interpretation of @href; in other words, we'd have > two attributes, but playing slightly different roles. This actually > seemed to me not just a compromise, but to be actually a better > solution than '@href everywhere' was. This is because: > > * it gives us a way of indicating an object that's a resource, > independent of host > language; > > * it allows us to define resources that are non-navigable. > > This last point is quite important, since in XHTML 2 @href _does_ mean > a navigable link anywhere it appears, so this would have been a > problem in the future. For example, if we were defining some kind of > SKOS relationships where there is no navigable end-point, we'd end up > with a 'navigable link' in XHTML 2, because that would be the only way > to express it. > > So that's the state of play on that issue, and although not everyone > is convinced that this is the best solution (for example, as Steven > rightly says, you now need to understand two attributes), at least it > gives us a way out if we want it. > > > RDFA-CORE > > Ok...that's the debate about @href and @resource. How does that relate > to the discussion on having a notion of RDFa-core? > > My RDFa-core posts were simply about trying to have a 'model' of RDFa > that stops us getting into these kinds of situations, where anything > is fair game for change, and the criteria for change is largely > subjective. Personally I'm not wedded to any one syntax, but what I am > wedded to is consistency--that is after all the whole point of RDFa. > So whilst I won't get worked up about having @href everywhere--or > not--what I do want to ensure is that there is some kind of consistent > picture that helps people understand RDFa. > > > LINK AND META EVERYWHERE > > To illustrate the problem I'm trying to address, let's look at another > issue (which is not actually in the issue-tracking system) 'link/meta > everywhere'. Just as we had '@href everywhere' for a long time, so too > we have <link> and <meta> everywhere in RDFa. But it transpired a > short while ago that some browsers move the link and meta elements > into the head of the document, losing all the important context > information. This means that we might as well remove that feature from > RDFa-in-HTML since it can't be supported. > > But that means that we now we have *two* changes that are not based on > anything intrinsic to the language: we've removed 'link and meta > everywhere' because some browsers won't support it, and we've removed > '@href everywhere' because it might be confusing for authors. > > You have to ask: what changes could be next? And what criteria could > be used to justify them? And you also have to ask, where does that > leave a language that _could_ support some of these features, such as > 'link and meta everywhere'? It seemed to me that trying to squeeze > language-specific features like this into RDFa itself, was going to > cause us problems for future host languages. > > So my suggestion is to simply say, why don't we 'unwind' all changes > that we made to the host language, and make a rule that we don't > actually change the host language at all. I appreciate that it might > unnerve you :), but it's not actually such a big change in terms of > work on the syntax, and it closes off some issues (9, 7(7), 12 and 34) > without much need for debate. (Fingers crossed.) > > Also, by making clearer, the distinction between core attributes (like > @about and @resource), and an 'interpretation' of HTML (like '@rel is > the predicate'), it also points towards a possible solution to issue > 3, because we could just add a new attribute for rdf:type to the core > attribute list. > > I'm really hoping that this gives you a picture of why I'm proposing > what I am, and that it's all about trying to close off the few > remaining issues, rather than making enormous changes. > > Regards, > > Mark >
Received on Friday, 1 June 2007 15:25:33 UTC