- From: <noah_mendelsohn@us.ibm.com>
- Date: Thu, 6 Dec 2007 12:44:34 -0500
- To: "Henry S. Thompson" <ht@inf.ed.ac.uk>
- Cc: www-tag@w3.org
Henry, Thank you for the hard work on this [1]. I think it represents real progress. I have a few comments on this draft: ---------- * My main concern is that the goals aren't stated clearly, the ones that are there are to some degree contradictory, and in any case I'm not sure I'm comfortable with them. From section 1: "That is, aside from the obligations imposed by the XML (and XML Namespace) recommendations themselves, what, if anything, ought to be done with a document whose media type tells you it's an XML document, before any application-specific processing is attempted?" This seems too imperative in style. First do this, then do that. I would prefer to see the goals grounded in the need to make Web documents self-describing. So, it's important that there be an agreed, standard interpretation of an XML documents, and we here try to set out what that is. The goal is not a set of steps, it's a preferred interpretation of the document. The steps may be a way of achieving the goal. "Or, to put it another way, if an author takes responsibility for the information in an XML document, exactly what is s/he taking responsibility for?" Closer, but that's not at all the same as the first quote. and it's still somewhat oblique I think. ---------- * From section 4: "There are three different ways in which the process of elaboration can be avoided, so that the unelaborated infoset is preserved: opting out, implicit quotation and explicit quotation. Opting out is trivial: Nothing in the definition of elaborated infosets requires a specification or processor to use it. So, for example, the next edition of XSLT probably should not mandate the elaboration of stylesheets, since on balance the presense therein of e.g. an xi:include element is most likely to be specifying a literal result element, and should not be elaborated." This highlights my concern about the goals. I thought the whole point was to have an interpretation that applies to >all< XML document, so that tools can be written that work across all of them. If particular languages can opt out of the rules, what are the goals again? (see point 1 above) ---------- * From section 2: "The default processing model question can be rephrased as "Is there an infoset other than the one produced by a conformant XML parser which can and should be defined?" I'm confused. I would have thought the answer to that was "trivially, yes!" I would have thought the question would be: of the many that can be defined and will be defined (e.g. results of an XInclude transform), is there one that should be blessed as conveying the preferred interpretation of the source document? Again, the goals need clarifying. ---------- * Question: if someone invents a new quoting element in a coupld of years, say <bi:betterInclude>, how does this get worked into the elaborated infoset, and how to people writing software learn the quoting rules? ---------- * Section 4.2: "The elaboration of an element II with this attribute is defined to be an otherwise identical element eII with the attribute removed, and the special property that it short-circuits further applications of E in search of a fixed-point." I can't prove it, but my intuition is that the removal of the quoting (or keeping it for that matter) could be problematic if there are scenarios in which multi-level quoting is required. Again, it's just an intuition, and probably not a good one. ---------- Overall, I'm a bit nervous that in spite of a lot of hard work on this, we don't quite know what we're doing yet, and we haven't shown that there's a mapping that applies in all cases (including XSLT stylesheets), that extends will as new transforms are invented, etc. So, I'm a bit nervous about the whole undertaking, but quite willing to plug ahead and see whether we can get something good out of this. Noah [1] http://www.w3.org/2001/tag/doc/elabInfoset-20071127/ -------------------------------------- Noah Mendelsohn IBM Corporation One Rogers Street Cambridge, MA 02142 1-617-693-4036 --------------------------------------
Received on Thursday, 6 December 2007 17:43:29 UTC