- From: Ivan Herman <ivan@w3.org>
- Date: Sat, 29 Dec 2012 21:04:19 +0100
- To: Sebastian Heath <sebastian.heath@gmail.com>
- Cc: RDFa Working Group <public-rdfa-wg@w3.org>
Sebastian, I am sorry not to have the time to go into the details of your use case right now. But I wanted to make a quick point. You seem to suggest that HTMLa+RDF Lite could retain the current handling of XML or HTML Literal, ie, not to generate those unless explicitly instructed through a @datatype usage, whereas the non-lite version could have the opposite behaviour. Is it what you suggest? I am afraid that would not fly if this is indeed what you propose. Indeed RDFa Lite is not a different language with different processing rules. It is only an editorial subset, so to say, reducing the number of attributes that are used. The current structure does not allow defining a different processing for Lite and for non-lite. Ivan --- Ivan Herman Tel:+31 641044153 http://www.ivan-herman.net (Written on mobile, sorry for brevity and misspellings...) On 29 Dec 2012, at 20:47, Sebastian Heath <sebastian.heath@gmail.com> wrote: > On Sat, Dec 29, 2012 at 8:25 AM, Ivan Herman <ivan@w3.org> wrote: >> I agree with you and Gregg. The issue on XML Literal has been discussed a >> lot. It wasn't an obvious issue, but the decision has been made. >> >> Procedurally, it is correct to say that this WG has the right to define the >> behaviour of HTML5+RDFa differently for XML Literals and/or for HTML >> literals. However, the discussions for RDFa Core, as well as for >> XHTML1+RDFa, obviously took into account the most important prospective >> deployment of RDFa, i.e., HTML5, too. I also do not see any new evidence in >> this thread that would justify essentially reopening this issue, and >> introducing a major incompatibility between XHTML1, SVG, etc., and HTML5. I >> am sorry, Andreas, but I am definitely not in favour of this change. >> >> Ivan >> >> --- >> Ivan Herman >> Tel:+31 641044153 >> http://www.ivan-herman.net >> >> (Written on mobile, sorry for brevity and misspellings...) > > > Ivan, > > Thank you for your response. And thank you for clarifying that the WG > can adapt the RDFa 1.1 Core document to the specific needs of an > (X)HTML5 context, though I'm sure we all agree that that is inherent > in the process of describing how RDFa works in a host language. > > And again thank you for indicating that there is a requirement for > new evidence. I am not sure why that is the case since this is a new > issue opened on "RDFa 1.1 in HTML", but if that requirement does > exist, I believe this situation meets it. Of course, that keeps us on > procedural issues, which are less interesting than the basic point of > making sure "RDFa 1.1 in HTML" is a well-constructed and robust spec > that can meet the needs of many users. But since the objections to > considering ISSUE 147 seem to be procedural, I'll address those. > > New Evidence: > > * The existence of RDFa Lite > When the decision to discard child elements when distilling RDF > triples from RDFa+XML was made (ISSUE 19) [1], RDFa Lite did not exist > [2]. This is relevant because it seems that a reason for discarding > child elements is how "semantic data is consumed in the marketplace" > [3]. > > I believe I'm on fairly firm ground in saying that one inspiration > for RDFa Lite was to ease the process by which semantic data is > firstly created and secondly consumed in an SEO oriented > "marketplace". Although I do not use RDFa Lite, I fully recognize its > need and utility. But to the extent that one downstream use of > semantic data is determining default behaviors, I suggest we can now > encapsulate those behaviors in RDFa Lite. Meaning, that RDFa Lite can > retain the default production of Plain Literals when processing HTML5. > In fact, I think that is a perfect use of RDFa Lite, one that was not > possible when ISSUE 19 was decided. This should not lead to ISSUE 19 > being re-opened, but rather the current ISSUE 147 being considered on > its merits. > > > * Use cases in which child elements in (X)HTML5 are not a mistake > > I think that such uses can be considered new evidence has already been > recognized by Manu's inclusion of point 2 in his list of items that > the WG should re-examine [4]. So perhaps the following is also my > contribution to that re-examination. > > Here's my use case and some of its history by way of explaining why I > raised this issue now and in the context of "RDFa 1.1 in HTML5": > > As I said, I edit an online scholarly journal "ISAW Papers" [5]. The > end result of the publication process will be the deposition of XHTML > files in the New York University Faculty Digital Archive for permanent > preservation. It is my hope to also use RDFa to encode the semantic > data in these articles. I have begun to do so and an example of the > current state of work can be seen in the publicly accessible version > of ISAW Papers 2 as delivered by the NYU library [6]. If you look in > the source of that page, you will see many @property values which have > child elements, in particular, dcterms:bibliographicCitation. It is > not a mistake that those are there, they are important, and it is > important to me that they be preserved in workflows that process this > data. That is the source of my request that ("non-lite") RDFa > distillers preserve that markup. > > But in terms of procedure and the requirement for new evidence, here > is where I am. For some time now I have been developing ISAW Papers > with XHTML+RDFa 1.0, which did preserve child elements. The RDFa Core > Rec came out in June. THe community's attention turned more firmly to > RDFa in HTML5, as did mine. In the fall I began converting my content > to HTML5 and RDFa 1.1. (If you poke around ISAW Papers you'll see > evidence of an ongoing process...) In making that conversion I saw > that child elements where discarded. This is a concern to me because > I am hoping to encode my semantic data using RDFa 1.1, then use > standardized tools that extract that semantic data, and then process > that semantic data for both automatic-agent and human consumption. In > all these cases, preservation of markup is extremely important. > > It did take me some time to confirm that the discarding of markup was > not caused by error on my part. Knowing now that it is a feature of > the REC, I have now reported my concern in the context of the "RDFa > 1.1 in HTML5", and I have made this report while the spec is a Working > Draft. I don't think it is unusual that I have found this issue only > after taking considerable time to work with both specs and hope > realities of my timing aren't determinative in addressing ISSUE 147. > To put that another way, I think I have done the "right thing" in > pursuing the conversion now and in offering my feedback to the WG. > > I do recognize that the development process for RDFa 1.1 Core looked > forward to its deployment in HTML5. Ivan, you noted this above. But I > do think its important that RDFa Core describes RDF in the context of > generic XML documents and so did not bear the burden of fully > addressing the role of RDFa in HTML5. This seems clear from the > well-understood need for the "RDFa 1.1 in HTML5" product that we are > working on now. > > * Accessibility > I am not an expert in this topic so I raise it with some hesitancy. > But I would like my XHTML to be accessible as defined by the W3's Web > Accessibility Initiative [7]. I see there that it suggests the use of > HTML markup to achieve its goals, see the suggested use of the dfn > element [8]. It is likely that such elements will end up in RDFa > marked content such as dcterms:abstract. The current "RDFa 1.1 HTML5" > spec discards that accessibility markup. But let me clear, I defer to > Shane's greater expertise or any other official feedback from the WAI > on this issue. > > > Ivan, on the basis of the above, I wonder if you would be willing to > reconsider your determination that insufficient new evidence has been > introduced in order to consider ISSUE 147 within its stated "RDFa 1.1 > in HTML5" context. > > Broadening this discussion slightly, in earlier messages I have made > what I think are substantive points as to why either rdf:XMLLiteral or > rdf:HTML should be the default production when parsing elements that > have child elements. I won't repeat those here, other than to note > that I highlighted issues of language, which I think are especially > relevant as RDFa is deployed in HTML5. It looks like there was some > consideration of language in the teleconference that resolved ISSUE > 19, with the suggestion that this is where people might want markup > preserved [9]. I agree and think "RDFa 1.1 in HTML5" is the right > place to pursue that topic. > > > To sum up with reference to previous messages: > > 1) The consideration of ISSUE 147 with in the context of the Working > Draft of "RDFa 1.1 in HTML5" is timely. > > 2) There is new evidence in the form of the existence of RDFa Lite, > the introduction of a use case in which child elements are not a > mistake, full consideration of multi-lingual issues as they appear in > HTML5 as used in the real world, and the possibility of WAI impact. > > 3) There is a substantive case for the default production of > rdf:XMLLiteral and rdf:HTML in the context of HTML5 and its variants. > See "2)" immediately above. > > 4) Some solutions have been offered in the form of: restricting the > default discarding of markup to RDFa Lite in HTML5, writing separate > specs for RDFa inXHTML5 and HTML5, re-enforcing that elements > without child markup should produce a Plain Literal. > > I do hope the above discussion allows us to move beyond procedural > issues to full consideration of the merits of ISSUE 147. > > My final point is that I hope it's clear that this issue is of great > importance to me. I want to use XHMTL+RDFa but this default > behavior is a real impediment. One that I have only recently > discovered. So I've tried to be clear in my > language (though it's hard to be concise!). Please don't take > that as abruptness or rudeness. > > Thank you, > > Sebastian. > > [1] http://www.w3.org/2010/02/rdfa/track/issues/19 > [2] http://www.w3.org/standards/history/rdfa-lite > [3] http://lists.w3.org/Archives/Public/public-rdfa-wg/2012Dec/0077.html > [4] http://www.w3.org/2010/02/rdfa/track/issues/147 > [5] http://isaw.nyu.edu/publications/isaw-papers > [6] http://dlib.nyu.edu/awdl/isaw/isaw-papers/2/ > [7] http://www.w3.org/WAI/ > [8] http://www.w3.org/TR/2012/NOTE-WCAG20-TECHS-20120103/H54 > [9] http://www.w3.org/2010/02/rdfa/meetings/2010-05-13#ISSUE__2d_19__3a__Default_generation_of_XMLLiterals >
Received on Saturday, 29 December 2012 20:04:43 UTC