[XML-DEV Mailing List Archive Home] [By Thread] [By Date] [Recent Entries] [Reply To This Message] Re: What is PI data exactly?
At 09:56 AM 10/16/98 +0100, Michael Kay wrote: >Meta-comment: we're suddenly getting a spate of comments that point to >little inconsistencies or ambiguities in the spec, reflecting the fact that >it is written very informally. I think the problems are particularly acute >when the spec tries to talk about the actions of "XML processors" or >"applications" because these notions are very fuzzy. Several of us on the Working Group complained about this at the time. This was always a problem with the SGML spec and was, in my opinion, made worse in XML by reference to "processors" rather than "parsers". The problem is that XML (like SGML) only defines a syntax, not an abstraction constructed from that syntax. In SGML, we got part of the way there by defining the SGML property set that defines the normative form for parsed SGML documents, but we *didn't* formally define the "grove construction process" by which you go from the syntax to the abstraction--that was mostly implicit in the property set definition and explicit in a few places, but ultimately underspecified (but we did have a reference implementation in James Clark's Jade processor). For XML, we need to have the same thing: a normative definition of the abtraction you get by parsing an XML document and a normative definition of the algorithm for going from the syntax to the abstraction (ideally the abstraction should be consistent with SGML's). That is, an abstract data model and construction algorithm. Note that the DOM is not this as it is an implementation-specific *object model* for a particular class of XML processor, not an abstract *data model* divorced from any specific implementation or type of processor. Until this is done, there will always be inconsistencies and ambiguities in the XML specification because there is no way to formally define what an "XML processor" is. Cheers, E. -- <Address HyTime=bibloc> W. Eliot Kimber, Senior Consulting SGML Engineer ISOGEN International Corp. 2200 N. Lamar St., Suite 230, Dallas, TX 75202. 214.953.0004 www.isogen.com </Address> xml-dev: A list for W3C XML Developers. To post, mailto:xml-dev@i... Archived as: http://www.lists.ic.ac.uk/hypermail/xml-dev/ To (un)subscribe, mailto:majordomo@i... the following message; (un)subscribe xml-dev To subscribe to the digests, mailto:majordomo@i... the following message; subscribe xml-dev-digest List coordinator, Henry Rzepa (mailto:rzepa@i...)
|
PURCHASE STYLUS STUDIO ONLINE TODAY!Purchasing Stylus Studio from our online shop is Easy, Secure and Value Priced! Download The World's Best XML IDE!Accelerate XML development with our award-winning XML IDE - Download a free trial today! Subscribe in XML format
|