[XML-DEV Mailing List Archive Home] [By Thread] [By Date] [Recent Entries] [Reply To This Message] Re: What is XML for?
Simon St.Laurent writes: > >The question that we're discussing is not whether the rich > >recursive and hierarchical structures that XML can model are > >useful (I know from eight years' experience that they are), but > >rather, whether XML itself -- that is, text files conforming to > >XML 1.0 -- should be used as the primary storage medium for large > >applications. > > That may be what you're hearing, but I think your assumption that > XML is a simple file format - that XML documents must be stored in > enormously long serial text files - is limiting your perspective > too much. We're just mixing up terms. XML documents *are* serial text files -- that's all that they can be. As soon as you slurp them up into alternative storage, they're not XML documents any more. They're just as important, just as interesting, and just as useful, but they are no longer in a format defined by the XML 1.0 specification, so literally speaking, they're not XML. In general, few high-speed, large-scale applications can afford repeated passes through serial text files (or even random access through reverse indices), so using XML (in the literal sense) for primary storage is impractical; there are, of course, exceptions -- for example, small bits of XML can be stored as blobs in relational databases. Paul's point, however, is that what's exciting about XML is what's exciting about working with recursive, hierarchical data structures in general. When people talk about non-textual XML, that's usually what they're really talking about. Personally, I have a strong LISP background going back to 1987 and an SGML background going back to 1991. I share Simon's excitement very much -- the world is a fascinating place when we let our data break out of tables. Here, for example, is a simplified natural language parse tree as a LISP list (the kind of thing we were playing with 12 years ago): (sentence (noun-phrase (modifier "The") (modifier "old") (noun "man")) (verb-phrase (verb "sat") (adverb-phrase (preposition "on") (noun-phrase (modifier "the") (noun "bench"))))) The AI movement in the 1970's and 1980's lived and breathed this stuff. It's easy to see how XML can provide an excelling language- and system-independent representation of this structure, but the idea of modelling information this way does not originate with XML, any more than it originated with SGML or with LISP. What Simon is saying, I think, is that he likes working with this kind of information, and that he would like to refer to the general idea of recursive, hierarchical data as "XML". I suppose it's OK -- I still want to call it "LISP" sometimes, but I'm afraid that people will laugh. All the best, David -- David Megginson david@m... http://www.megginson.com/ 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
|