Detecting inherited language

> You need more than to recurse, you also need to look at the <meta> and 
> at the end you need to XHR your own location and look at 
> Content-Language. It's all doable, but a bit cumbersome.

While that will work most of the time, it’s not particularly robust because the resource will need to be retrieved again, which may fail to match the current resource for many reasons (cache misses, network failures, resource may have changed in the meantime, etc.)  But for static language detection test cases, this may probably be adequate.

> And Richard, I forget when this came up, but the conclusion last time 
> around was that this information was unfortunately not exposed in the 
> DOM so you indeed have to get it yourself.

I brought up this issue in the RDFa working group.  See:
<http://lists.w3.org/Archives/Public/public-rdfa-wg/2013May/0045.html>
and the replies.  The issue was resolved by adding a note
to the RDFa spec highlighting this issue:
<http://lists.w3.org/Archives/Public/public-rdfa-wg/2013Jun/0003.html>