Re: @lang and @xml:lang in XHTML+RDFa 1.1

Hello,

2010/1/2 Shane McCarron <shane@aptest.com>:
> I am in the process of producing an XHTML+RDFa 1.1 editors draft, and I am
> pondering what the inclusion of @lang means for the processing rules.  To
> me, it makes perfect sense to say that @lang and @xml:lang both can define
> the language of an element, and that @xml:lang takes precedence.  This is
> what XHTML 1.1 says. Does anyone see a problem with this?


As I posted almost a year ago [1], I've been thinking that the use of
X/HTML lang (xml:lang) attribute to generate RDF lang tag might be one
of the most problematic parts in RDFa.

Generally, HTML authors put lang attribute on the <html> element,
maybe in order to take advantage of assistive technology etc., not
paying attention that the attribute value is inherited through the
elements tree. So we tend to write something:

<html lang="ja" xml:lang="ja">
...
<p xmlns:dc="http://purl.org/dc/terms/">
Updated: <span property="dc:modified">2010-01-13</span>...
</p>

which generates weird triple:

<> dc:modified "2010-01-13"@ja .

I've witnessed bunch of nonsense lang-tagged triples came from RDFa
documents. We can cancel lang attribute with empty lang="" or
xml:lang="", or can add datatype attribute, but very few people do
this in practice. And if there is an English or French name marked
with property="foaf:name", such name will be tagged with @ja.

Another concern is, if a user copy/paste the above paragraph into
his/her HTML, that will be a valid RDFa but will generate different
triple (without lang tag).

If lang attribute is not included in RDFa 1.1 processing model, but
allowed to use for accessibility purpose, then we can write only lang
attribute in <html> element to avoid this confusion. I'm not sure
whether this is a good solution, but RDFa 1.1 should be a chance to
clear this unwelcome situation.

best regards,


[1] http://lists.w3.org/Archives/Public/public-rdf-in-xhtml-tf/2009Jan/0154.html

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Received on Wednesday, 13 January 2010 12:55:39 UTC