[uf-discuss] 2 billion hCards! gathering material for a "microformats.org turns 5" blog post

Toby Inkster mail at tobyinkster.co.uk
Wed Jul 7 04:43:52 PDT 2010

On Wed, 7 Jul 2010 02:25:38 -0700
Tantek Çelik <tantek at cs.stanford.edu> wrote:

> E.g. Wordpress.org results don't have any RDFa.
> View source and the only thing even remotely resembling you see is:
> <meta property="fb:page_id" content="...">
> - which is simply use of an invalid "property" attribute (in XHTML
> 1.0). The qname "fb:" is not defined anywhere.

In the current RDFa 1.1 drafts, this is allowed, though its meaning is
not likely what the authors of this page intended. In 1.1, prefixes
which are not bound to anything are assumed to be absolute URIs.

The page at http://wordpress.org/ does actually contain 3 triples if
evaluated as RDFa 1.0, though they're each the result of RDFa
grandfathering in certain HTML 4/XHTML 1 semantics.

The question "how many pages contain RDFa?" is only meaningful if
certain qualifications are added... Does broken RDFa count? Do
grandfathered rel/rev values count? &c.

In fact, "how many pages" questions about the Web are not especially
meaningful. Say Google added an hCard to its search result pages,
replacing its current logo with something like this:

	<span class="vcard">
		<a href="/" class="url">
			<img class="logo fn org"
			alt="Google" src="..." />

Are the search results for "foo" and "bar" different pages? What about
the search results for "100000000001" and "100000000002"? Because if
they are, that's over a hundred billion hCards online.

Toby A Inkster
<mailto:mail at tobyinkster.co.uk>

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