RE: [xml-dev] xml:href, xml:rel and xml:type

["Rushforth, Peter" <Peter.Rushforth@NRCan-RNCan.gc.ca>]

Hi Liam,

Thanks for your reply.

> 
> > As I understand it, mastery of the web was a goal of XML, 
> so I'm just 
> > dreaming a little.
> 
> It was not a goal of XML.
> 
> The primary goal of XML was getting existing SGML documents 
> and work-flows onto the Web. The work was originally called Web SGML.

From "http://www.w3.org/TR/xml/#sec-origin-goals";

The design goals for XML are:

1. XML shall be straightforwardly usable over the Internet.

OK, this is not "mastery of the web", but the Web is an important
application of the internet.  

> Your comment did I think reach the XML Core Working Group; 
> the group meets two or three times a month for half an hour, 
> so don't expect an immediate response :-)

Sorry, I should have posted here in the first place anyway.

> However, I think 
> the first reaction was to point you towards XLink and XPointer.

Yes, others have pointed that out.  I'm thinking about RESTful use of
XML.  REST is the basis on which the Web's protocol is designed.
"typed" links are a fundamental part of REST, I think.
  
So, my question is, what is the simplest change that could be made
to XML which would enable its "success" on the web?  My suggestion
is to insert linking lower down in the XML technology stack than
what is done by XLink.

Others also predicted that my suggestion would not be 'popular'.
I'm OK with that, but I wanted to hear from the technology implementers
of what would break if such a change was made.  
> 
> If "mastery of the Web" _had_ been a goal, XML would have 
> been very different, as Jeni Tennyson pointed out in her 
> keynote at XML Prague this year.

Yes, I saw the video, but I forget this specific point.  Did she say
how it would have been different? 

> To answer a more explicit question (from a personal 
> perspective), the cost of introducing xml:href would be 
> risking breaking existing XML systems,

I've tried putting these
attributes on XML source and running XSLT against them, no
obvious problems.  I found no support for XLink in my XML IDE. 

> which are far more 
> likely to work with xlink:href. 

I know there are vocabulary standards which use xlink.  Of course that
means there are processors which use it too.  I think that if you need
the power of describing links semantically etc, you should use it.  But
not everyone needs this power.  For that matter, one is not obliged to
use XLink, you can "roll your own" linking scheme, which your own processors
can leverage.

> And there's no clear benefit.

OK, I think there is.  I think that having a simple standard that
does not have to be declared by the user would allow linking of XML documents
"on the web", with design aligned with that of the web, hence xml:type and possibly xml:hreflang.

BTW, I think the JSON community is considering the same problem:
http://www.mnot.net/blog/2011/11/25/linking_in_json


> 
> The biggest problem I see with XLink is that it did not 
> address "link discovery through architectural forms" - the 
> process of saying, "in this XML vocabulary, the "cf" 
> attribute on any element with three vowels in the element 
> name is a link constructed by using the template
>   concat(@cf, "?", local-name(), "=", .)

I have been wondering about how to use URI templates in XML:
http://www.rfc-editor.org/rfc/rfc6570.txt

Is this a similar idea?

Cheers,
Peter