OASIS Mailing List ArchivesView the OASIS mailing list archive below
or browse/search using MarkMail.

 


Help: OASIS Mailing Lists Help | MarkMail Help

 


 

   Re: [xml-dev] RDDL (was RE: [xml-dev] Negotiate Out The Noise)

[ Lists Home | Date Index | Thread Index ]

At 7:30 PM -0800 1/17/02, Paul T wrote:

>PS. It appears that people, who write articles about RDDL,
>are already providing  the general public with misleading
>information about RDDL (exactly, like it was with
>XML Namespaces. As we should remember, each
>and every XML book or article was explicitly saying that
>Namespaces URLs "point to nothing" and that's the
>idea of them. Which is no longer true.)
>

Really? You've really read "each and every" one? Looking at my own 
books I see in XML in a Nutshell, 1st edition:

Namespace URIs do not necessarily point to any actual document or 
page. In fact, they don't have to use the http scheme. They might 
even use some other protocol like mailto in which URIs don't even 
point to documents. However, if you're defining your own namespace 
using an http URI, it would not be a bad idea to place some 
documentation for the specification at the namespace URI. The W3C got 
tired of receiving broken link reports for the namespace URIs in 
their specifications so they added some simple pages at their 
namespace URIs. You are by no means required to do this, though. Many 
namespace URIs lead to 404-Not Found errors when you actually plug 
them into a web browser. Namespace URIs are purely formal 
identifiers. They are not the addresses of a page, and they are not 
meant to be followed as links.

The XML Bible is a little less clear that you can place something at 
the end of a namespace URI, but still doesn't come close to saying 
that you can't and that that's the whole idea of them. From the 1st 
edition:

The URI that defines a namespace is purely formal. Its only purpose 
is to group and disambiguate element and attribute names in the 
document. It does not necessarily point to anything. In particular, 
there is no guarantee that the document at the URI describes the 
syntax used in the document; or, for that matter, that any document 
exists at the URI. Having said that, if there is a canonical URI for 
a particular XML application, then that URI is a good choice for the 
namespace definition.

These were all written pre-RDDL but seem pretty accurate to me.
-- 

+-----------------------+------------------------+-------------------+
| Elliotte Rusty Harold | elharo@metalab.unc.edu | Writer/Programmer |
+-----------------------+------------------------+-------------------+
|          The XML Bible, 2nd Edition (Hungry Minds, 2001)           |
|              http://www.ibiblio.org/xml/books/bible2/              |
|   http://www.amazon.com/exec/obidos/ISBN=0764547607/cafeaulaitA/   |
+----------------------------------+---------------------------------+
|  Read Cafe au Lait for Java News:  http://www.cafeaulait.org/      |
|  Read Cafe con Leche for XML News: http://www.ibiblio.org/xml/     |
+----------------------------------+---------------------------------+




 

News | XML in Industry | Calendar | XML Registry
Marketplace | Resources | MyXML.org | Sponsors | Privacy Statement

Copyright 2001 XML.org. This site is hosted by OASIS