RDDL proposal from Micah Dubinko

The 11 December Working Draft of XHTML 2.0 chagnes the <meta> element to
allow content (instead of the previous 'content' attribute).

Further proposals for <meta> include adding an 'about' attribute, which
would provide metadata about resources other than the containing document,
and allowing nested <meta> elements, which would provide a lightweight way
to express blank nodes.

This opens the possibility of a RDDL document that is nothing but
off-the-shelf XHTML 2.0. 

The upside is that no new markup is needed, and the <meta> approach is
widely understood and deployed (at least in HTML/XHTML 1.0 terms). This
approach is 100% DTD-validatable, which the XHTML guys tell me is important.
This approach is very easy to look at and understand.

The downside is that a further change to XHTML 2.0 is needed. If XHTML 2.0
doesn't accept the proposals mentioned above, then this syntax leaves little
to offer.

Syntax:

<head>

<link rel="schema.rddl" href="http://rddl.org" />

<meta about="http://example.com/L" name="rddl.related">
  <meta name="rddl.location">
    http://example.com/schemas/L.rng
  </meta>
  <meta name="rddl.nature">
    http://relaxng.org/ns/structure/1.0
  </meta>
  <meta name="rddl.purpose">
    http://www.rddl.org/purposes#validation
  </meta>
</meta>

<meta about="http://example.com/L" name="rddl.related">
  <meta name="rddl.location">
    http://example.org/style/L.css
  </meta>
  <meta name="rddl.nature">
    http://www.isi.edu/in-notes/iana/assignments/media-types/text/css
  </meta>
  <meta name="rddl.purpose">
    http://www.rddl.org/purposes#render
  </meta>
</meta>
...
</head>

Thanks,

.micah

========

Tim Bray:

Here's the example.  There's a namespace whose name is 
"http://example.com/L".  It has a RelaxNG schema at 
"http://example.com/schemas/L.rng" with nature 
"http://relaxng.org/ns/structure/1.0" and purpose 
"http://www.rddl.org/purposes#validation".  It has a CSS stylesheet at 
"http://example.org/style/L.css" with nature 
"http://www.isi.edu/in-notes/iana/assignments/media-types/text/css" and 
purpose "http://www.rddl.org/purposes#render".

Please propose examples of how you think this information ought to be 
embedded in a RDDL instance, in a message to www-tag with the title 
"RDDL proposal from <your name here>".  The proposals should include:

- the syntax
- the embedding mechanism (in a new element, in the header or body, 
whatever)
- what you consider the pros and cons of your approach

Sooner is better.

Received on Monday, 16 December 2002 20:05:36 UTC