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1

Does anyone know whether it's permissible to have both the @rel and @rev attributes on an element in RDFa?

This seems like a slightly odd thing to me if it is allowed since it results in two triples like so:

:a :b :c .
:c :b :a .

Maybe I'm missing it in the specifcation document (it is a long document) but is this expressly forbidden or is this legal syntax?

flag	asked Feb 5 at 14:23 Rob Vesse 1,190●10

2

What’s so unusual about this pair of triples? Seems pretty natural for foaf:knows or any other property that could be considered symmetric. – Vasiliy Faronov Feb 5 at 18:02

good point, just me being slow I think – Rob Vesse Feb 6 at 15:26

jsightler · Accepted Answer · 2010-02-05 21:44:25Z UTC

1

:a :loves :c .
:c :loves :a .

Does that seem so unusual? I think its both legal, and possibly even expected in many cases.

answered Feb 5 at 21:44

jsightler
203●5

	+1, no with hindsight kinda an obvious case – Rob Vesse Feb 6 at 15:26
	True - been there many times before myself. :) – jsightler Feb 7 at 21:45

Gregg Kellogg · Answer 2 · 2010-02-16 03:36:31Z UTC

This is essentially the RDFa test 0006, which uses both rev and rel on the same element:

<html xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:foaf="http://xmlns.com/foaf/0.1/">
  <head>
    <base href="http://example.com/test0006"/>
    <title>Test 0006</title>
  </head>
  <body>
    <p>
      This photo was taken by
      <a about="photo1.jpg" rel="dc:creator" rev="foaf:img"
        href="http://www.blogger.com/profile/1109404">Mark Birbeck</a>.
    </p>    
  </body>
</html>

You can try out sample RDFa (or any type of RDF) through my distiller at http://kellogg-assoc.com/distiller, which uses the RdfContext Ruby gem.

Ivan · Answer 3 · 2010-02-17 13:41:28Z UTC

1

The answer is: yes, it is allowed. I agree that it is not widely used but, in a way, it would be more convoluted (spec-wise) to disallow it than to allow it!

answered Feb 17 at 13:41

Ivan
171●2

Both @rel and @rev on one element in RDFa

3 Answers