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Re: Implementation issue with TC#78

From: Mark Birbeck <mark.birbeck@webbackplane.com>
Date: Wed, 28 May 2008 23:16:13 -0700
Message-ID: <ed77aa9f0805282316q6672fa0cl4bd513b3e22ab3ca@mail.gmail.com>
To: "Manu Sporny" <msporny@digitalbazaar.com>
Cc: "RDFa mailing list" <public-rdf-in-xhtml-tf@w3.org>

Hi Manu,

Your implementation is correct.

I mentioned this a while back--that you will get the same triple, once
per predicate, when using hanging rel's--and the general feeling was
to just leave it; it would require yet another flag and another test,
and although not that complicated, it's still another rule.

I believe at the time this was raised that Ivan provided an example of
other situations in RDF where you can end up with the same triple
repeated in a graph, so it was felt that having duplicates was not an
enormous problem. (I don't recall his example, though.)

Regards,

Mark

On Wed, May 28, 2008 at 9:01 PM, Manu Sporny <msporny@digitalbazaar.com> wrote:
>
> Just a quick question to those that are implementing - for TC#78, I just
> want to make sure that other implementations are doing the same things
> as mine... I'm getting the same triple generated twice per the Syntax
> processing rules:
>
> --------------------------------------------------------------------------
>
> @prefix foaf: <http://xmlns.com/foaf/0.1/> .
> _:bnode0
>   <http://xmlns.com/foaf/0.1/name>
>      "Ivan Herman" .
> <http://www.example.org/#somebody>       <------------------------ ONCE
>   <http://xmlns.com/foaf/0.1/knows>
>      _:bnode0 .
> _:bnode0
>   <http://xmlns.com/foaf/0.1/mailbox>
>      <mailto:ivan@w3.org> .
> <http://www.example.org/#somebody>       <------------------------ TWICE
>   <http://xmlns.com/foaf/0.1/knows>
>      _:bnode0 .
> _:bnode1
>   <http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
>      <http://xmlns.com/foaf/0.1/Person> .
> _:bnode1
>   <http://xmlns.com/foaf/0.1/name>
>      "Mark Birbeck" .
> <http://www.example.org/#somebody>
>   <http://xmlns.com/foaf/0.1/knows>
>      _:bnode1 .
>
> ---------------------------------------------------------------------------
>
> I'm unsure if this is a bug, or an issue with the Syntax document... Is
> anybody else seeing this double-generation of the same triple?
>
> The first time it's generated is from step #11:
>
>   // 11. If the [skip element] flag is 'false', and either: the
>   // previous step resulted in a 'true' flag, or [new subject] was
>   // set to a non-null value, then any [incomplete triple]s within
>   // the current context should be completed:
>
> after processing:
>
>  <p property="foaf:name">Ivan Herman</p>
>
> The second time it's generated is from step #11, after processing:
>
>  <p rel="foaf:mailbox"
>    resource="mailto:ivan@w3.org">mailto:ivan@w3.org</p>
>
> This happens because [new subject] is set to a non-null value in both
> cases... so, are we supposed to generate two identical triples and let
> the RDF graph merge the two identical nodes or is there something wrong
> with my code?
>
> -- manu
>
> --
> Manu Sporny
> President/CEO - Digital Bazaar, Inc.
> blog: DB Launches Medical Record Sales Service with Shepherd Medical
> http://blog.digitalbazaar.com/2008/02/24/health2trade/
>
>
>



-- 
Mark Birbeck, webBackplane

mark.birbeck@webBackplane.com

http://webBackplane.com/mark-birbeck

webBackplane is a trading name of Backplane Ltd. (company number
05972288, registered office: 2nd Floor, 69/85 Tabernacle Street,
London, EC2A 4RR)
Received on Thursday, 29 May 2008 06:16:54 GMT

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