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Re: Fragids status report [partial]: ACTION-567

From: Henry S. Thompson <ht@inf.ed.ac.uk>
Date: Wed, 19 Oct 2011 11:58:04 +0100
To: Jonathan Rees <jar@creativecommons.org>
Cc: Noah Mendelsohn <nrm@arcanedomain.com>, www-tag@w3.org
Message-ID: <f5b62jlfdtv.fsf@calexico.inf.ed.ac.uk>
[coming late to the party]

Not sure whether what follows changes the substance of your analysis,
but for the record. . .

Jonathan Rees writes:

> Here are some of my notes on the subject...
> . . .
> Here is one of the examples in question:
>
> <p about="#bbq" typeof="cal:Vevent">
>       I'm holding
>       <span property="cal:summary">
>         one last summer barbecue
>       </span>,
>       on
>       <span property="cal:dtstart" content="2015-09-16T16:00:00-05:00"
>             datatype="xsd:dateTime">
>         September 16th at 4pm
>       </span>.
>     </p>

Note that there is _no_ anchor element for 'bbq'.  So per XPointer 
http://example.org/summer#bbq "is in error":

  If no element information item is identified by a shorthand
  pointer's NCName, the pointer is in error. [1]

Note however that

  Conforming XPointer processors must report XPointer Framework errors
  to the application. Applications are free to terminate or recover
  from XPointer Framework errors in any fashion. [2]

So arguably RDFa is in good shape here -- all it has to do is specify
its semantics as a form of error handling.

> . . .

> There is a similar example in the draft where the RDF seems to say that a URI
> refers to something that can have a foaf:name and a foaf:homepage;

Again, there is no anchor element, so per the above no substantive
problem.

> and a third example where the URI refers to something having a
> dc:source property.

In this case there _is_ an anchor element:

    <blockquote about="#q1" rel="dc:source" resource="urn:ISBN:0140449132" >
      <p id="q1">
        Rodion Romanovitch! My dear friend! If you go on in this way
        you will go mad, I am positive! Drink, pray, if only a few drops!
      </p>
    </blockquote>

but in this case it seems at least plausable that the XML 'p' element
_is_ the referent of the hash URI in question.

So arguably _on the examples in the spec_ no problem arises.

None-the-less it is reasonable to assume that there _will_ be examples
which will manifest the problem you analyse, so I'm not saying we can
all blythely go our merry ways. . .

ht

[1] http://www.w3.org/TR/xptr-framework/#shorthand
[1] http://www.w3.org/TR/xptr-framework/#conformance
-- 
       Henry S. Thompson, School of Informatics, University of Edinburgh
      10 Crichton Street, Edinburgh EH8 9AB, SCOTLAND -- (44) 131 650-4440
                Fax: (44) 131 651-1426, e-mail: ht@inf.ed.ac.uk
                       URL: http://www.ltg.ed.ac.uk/~ht/
 [mail from me _always_ has a .sig like this -- mail without it is forged spam]
Received on Wednesday, 19 October 2011 10:58:33 UTC

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