W3C home > Mailing lists > Public > public-rdfa-wg@w3.org > December 2012

"RDFa 1.1 in HTML5" default to generating XMLLiteral for content that contains elements

From: Sebastian Heath <sebastian.heath@gmail.com>
Date: Fri, 28 Dec 2012 03:44:52 -0500
Message-ID: <CACsb_1qWAM4p6Cpv1n05gFcbGywHhqchnBjT17JwhzSMjO7o+w@mail.gmail.com>
To: RDFa WG <public-rdfa-wg@w3.org>
Please open a new issue on "RDFa 1.1 in HTML5" to reflect my request
that XMLLitterals be generated when processing content that contains
elements.

 HTML5 and its variants such as XHTML5 provide a rich set of elements
that content creators use to indicate many aspects of the texts they
are representing. When processing RDF in attributes, the "RDFa 1.1 in
HTML5" specification [1] should by default require preservation of all
intentional markup. This is good practice. In particular, the working
group should not assume that elements in content marked with the
@property attribute are there by mistake. Nor should the replication
of namespaces in the output be considered garbage.

 For example, in the following markup:


 <div typeof="dc:bibliographicResource">
   <span property="dc:bibliographicCitation">Robert Palter. (1970).
<i>The <span xml:lang="la">Annus mirabilis</span> of Sir Isaac Newton,
1666-1966</i>. Cambridge: M.I.T. Press</span>
 </div>

it should be assumed that the 'i' and 'span' elements that are
children of the @property="dc:bibliographicCitation" are intentional
so that an XMLLiteral should be produced that preserves this markup.
Stripping these out is unnecessary and changes the nature of the
content.

 I believe this is a deviation from step 11 of the processing rules as
defined in "7.5 Sequence" of the RDFa Core [2]. This should be adapted
so that the default action is to generate an XMLLiteral as:

 "The value of the XML literal is a string created by serializing to
text, all nodes that are descendants of thecurrent element, i.e., not
including the element itself, and giving it a datatype of XMLLiteral
in the vocabulary http://www.w3.org/1999/02/22-rdf-syntax-ns#. The
format of the resulting serialized content is as defined in Exclusive
XML Canonicalization Version [XML-EXC-C14N]."

 If the above is adopted, the case of HTML5 snippets that cannot be
rendered as valid XMLLiterals needs to be addressed. That such
snippets may present difficulties should not be a reason to default to
the discarding of useful markup in XHTML5 contexts, nor in XHTML 1.1
documents processed according to the XHTML5 rules. Alternatively, it
may be necessary to define separate specifications for RDFa 1.1 in
HTML5 and RDFa 1.1 in XHTML5.

 Thank you,

 Sebastian.

[1] Currently at http://www.w3.org/TR/2012/WD-rdfa-in-html-20121213/
[2] http://www.w3.org/TR/rdfa-syntax/#s_sequence
Received on Friday, 28 December 2012 08:45:20 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 21:19:57 UTC