Re: [xml-dev] My proposal: Implicit namespaces

[Liam Quin <liam@w3.org>]

On Thu, Aug 06, 2009 at 03:16:58PM +0100, Dave Pawson wrote:
> On 08/06/2009 10:21 AM, Michael Kay wrote:
[...]
>> Another way to achieve this goal is to allow the designer of an XML
>> vocabulary (=a set of namespaces) to define
>> 
> >(a) a list of predeclared namespace prefixes for that vocabulary
>> (b) a list of local names that are known to be in each of those namespaces
>> 
>> When invoking an XML parser, the user should be able to reference this
>> "vocabulary definition",
[...]

>> An "nnML parser" is then an XML parser with built-in knowledge of the
>> nnML vocabulary definition.

This is very close to the proposal I've made...  although much more
complex than Tim Bray's idea.

> So for docbook you'd have an author include all 300+ namespaced elements ?

You only need to list those elements that can occur embedded in another
vocabulary, plus the top-level element.  For example, a list item might
not make sense without a containing list.  So, a docbook list would
automatically introduce the docbook namespace for all the elements it
contained (until you got down to ones that implied some other
namespace, such as "svg" perhaps).

>    Fine if Norm had them somewhere on the net I could reference them,
> but simply not practical to inline them in the document surely?

You'd have a reference, wich could be cached.

The biggest difficulty I had was software that refused to process XML
documents with qnames a:b where "a" had not been declared using xmlns;
I'd thought of allowing some other prefix such as "_" but then an
escaping machanism becomes needed for pepole already using "_" in
names...  In particular, I anted a proposal that could be made to
work without undue emotional trauma (to quote Jon Bentley) in
today's Web browsers.

Liam

-- 
Liam Quin, W3C XML Activity Lead, http://www.w3.org/People/Quin/
http://www.holoweb.net/~liam/ * http://www.fromoldbooks.org/