[XML-DEV Mailing List Archive Home] [By Thread] [By Date] [Recent Entries] [Reply To This Message]

Re: Namespaces and Schemes

  • From: "Simon St.Laurent" <simonstl@s...>
  • To: xml-dev@l...
  • Date: Wed, 29 Nov 2000 09:44:55 -0500

Re: Namespaces and Schemes
At 10:02 AM 11/29/00 +0000, Henry S. Thompson wrote:
>  The connection between instance and schema can be established in a
>  number of ways:
>
>   1) An application may have a schema built in, and always use that one;
>   2) An application may allow a user to provide one or more schema
>      documents, e.g. on the command line, for use in validation;
>   3) An instance may contain
>      {http://www.w3.org/2000/10/XMLSchema-instance}schemaLocation
>      attributes, which in turn associate namespaces with the location 
>      of schema documents for that namespace, and an application may
>      exploit this to find those documents;
>   4) An application may attempt to dereference namespace URIs and use 
>      schema documents found as a result.
>
>   The XML Schema draft spec. does _not_ mandate a particular order in
>   which these strategies should be followed, if more than one is
>   supported, but does encourage processors to support all of (2) -- (4).

And just to make the point yet again, lest anyone think Henry's word is the
final word on this issue, option #4 remains controversial and weakly
defined.  Applications which expect to be able to dereference namespace
URIs and find schemas should be prepared to be disappointed.  Likewise,
developers who rely on namespace URIs to point to their schemas shouldn't
expect applications to necessarily look there.

I'd suggest that we start talking about a clearer definition of what a
namespace is and what might 'live' there, but it seems to be one of those
dangerous topics.

Simon St.Laurent
XML Elements of Style / XML: A Primer, 2nd Ed.
XHTML: Migrating Toward XML
http://www.simonstl.com - XML essays and books

PURCHASE STYLUS STUDIO ONLINE TODAY!

Purchasing Stylus Studio from our online shop is Easy, Secure and Value Priced!

Buy Stylus Studio Now

Download The World's Best XML IDE!

Accelerate XML development with our award-winning XML IDE - Download a free trial today!

Don't miss another message! Subscribe to this list today.
Email
First Name
Last Name
Company
Subscribe in XML format
RSS 2.0
Atom 0.3
 

Stylus Studio has published XML-DEV in RSS and ATOM formats, enabling users to easily subcribe to the list from their preferred news reader application.


Stylus Studio Sponsored Links are added links designed to provide related and additional information to the visitors of this website. they were not included by the author in the initial post. To view the content without the Sponsor Links please click here.

Site Map | Privacy Policy | Terms of Use | Trademarks
Free Stylus Studio XML Training:
W3C Member
Stylus Studio® and DataDirect XQuery ™are products from DataDirect Technologies, is a registered trademark of Progress Software Corporation, in the U.S. and other countries. © 2004-2013 All Rights Reserved.