- From: C. M. Sperberg-McQueen <cmsmcq@acm.org>
- Date: 03 Oct 2003 22:22:18 +0200
- To: Dave Beckett <dave.beckett@bristol.ac.uk>
- Cc: W3C XML Schema IG <w3c-xml-schema-ig@w3.org>, www-rdf-comments@w3.org
Colleagues, thank you for your response to our comment. A full account of our formal responses to your responses is attached to http://lists.w3.org/Archives/Public/www-rdf-comments/2003OctDec/0011.html For the sake of those who are trying to track this particular issue using the email archives, our response on this topic is given below. -C. M. Sperberg-McQueen for the XML Schema WG On Tue, 2003-04-29 at 21:05, Dave Beckett wrote: > Dear Colleagues > > The RDF Core WG has considered your last call comment captured in > > http://www.w3.org/2001/sw/RDFCore/20030123-issues/#xmlsch-11 > > (raised in section > "4.4. Normative specification of XML grammar (policy, substantive)" of > http://lists.w3.org/Archives/Public/www-rdf-comments/2003JanMar/0489.html ) > > The main points you raised in this comment are: > > 1) RDF/XML is defined in "what is very nearly a character-level BNF > [which] is at best a missed opportunity and at worst a serious > mistake." > - obscuring important parts of the document type > - making it very difficult for the reader to actually > understand what is and isn't actually allowed. > - confusing layers > > RDF/XML is entirely layered on the XML Infoset as defined in > Syntax Data Model > http://www.w3.org/TR/rdf-syntax-grammar/#section-Data-Model > and is not defined at the character-level. > > All XML detail is handled by the XML specifications, not this > document - deployed RDF/XML applications are entirely built on > standard XML tools. In layering on the XML infoset, we leave only > the important parts of RDF/XML that users and application writers > need be concerned about - elements, attributes, whitespace and text. > > It would have been a mistake to gloss over where, say, the whitespace > was significant and where it was ignored - which was one problem with > the original RDF M&S specification. > > > 2) Rules out XML documents not parsed from character streams (such as DOM) > > This was explicitly called out: > [[ > This model illustrates one way to create a representation of an > RDF Graph from an RDF/XML document. It does not mandate any > implementation method - any other method that results in a > representation of the same RDF Graph may be used. > > In particular: > ... > * This specification does not require the use of [XPATH] or [SAX2] > ]] > http://www.w3.org/TR/rdf-syntax-grammar/#section-Data-Model > > If a DOM interface can provide the very few (4) XML Infoset Infoitems > that are needed here, it is not ruled out. > > > 3) Suggests a two-step approach first mapping to canonical RDF form > constrained by DTD or XML Schema > > An approach using a mapping to a canonical RDF written in XML is > related to issue xmslch-10 where we explain why we didn't feel we > could do this under the current charter. It certainly would have > been useful and helped. > > The model and grammar used here closely matches how many RDF/XML apps > were written, in a token matching style that can be used with > standard syntax lexers and grammar generators. This approach has > proved suitable after other implementor feedback. > > > > The RDF Core Working Group has decided: > > http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2003Apr/0361.html > > that the explanation above answers your comment as a clarification. > > Please reply to this email, copying www-rdf-comments@w3.org indicating > whether this decision is acceptable. > > Thanks > > Dave Thank you. We realize that this is a difficult area, but we believe that it would be a mistake for W3C to move forward with a new version of the RDF specifications without undertaking the work of a revision of the syntax. We regret that we must dissent formally from your resolution of this issue. The current mismatch between RDF syntax and off-the-shelf XML tools has not become easier to bear as time goes on; we believe it must be addressed.
Received on Friday, 3 October 2003 16:23:22 UTC