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Re 2: PROPOSAL: Restrict @prefix declaration to the root element

From: Ivan Herman <ivan@w3.org>
Date: Wed, 10 Aug 2011 10:04:32 +0200
Cc: Manu Sporny <msporny@digitalbazaar.com>, RDFa WG <public-rdfa-wg@w3.org>
Message-Id: <A22B02C8-EA7C-4336-9134-6654A06E22FF@w3.org>
To: Ivan Herman <ivan@w3.org>
I had some additional discussions with Manu on this issue and I understand where the request comes from. However, I do not see a way around the issue referred to below.

One compromise solution would be that, at least in HTML, @prefix would be restricted to the <html>, <head> and <body> elements. Ain't pretty, but works.

Ivan

On Aug 2, 2011, at 13:51 , Ivan Herman wrote:

> This proposal would lead to major issues with character encoding, see
> 
> http://lists.w3.org/Archives/Public/public-rdfa-wg/2011Apr/0107.html
> 
> Executive summary of that mail: HTML5 works with content sniffing to find out the character encoding of the source (looking for a relevant <meta> element in the head). This is done by HTML parsers, too, not only browsers. Having lots of prefix declarations in the <html> elements might lead to erroneous character encoding in the literal objects of the generated RDF; and there is no real defense against that (unless the HTTP return header provides a correct character encoding, but that is not always the case).
> 
> Actually, the advise (currently in the Primer, too) is _not_ to put too many @prefix declaration in the <html> element to avoid such issues, but put them into, say, the <body> element.
> 
> I do not think we should do this.
> 
> Ivan
> 
> On Jul 19, 2011, at 04:54 , Manu Sporny wrote:
> 
>> This proposal was raised during the telecon last week[1]. Since document
>> authors can declare @prefix anywhere in the document, they could
>> introduce authoring mistakes due to copy-paste. That is, if they do not
>> pay attention to where the @prefix is declared, they may accidentally
>> attempt to express triples that do not have a CURIE prefix defined.
>> 
>> While a number of people in the group feel that copy-paste issues are
>> not really that prevalent, limiting the use of @prefix to just the root
>> element of the document may decrease the possibility of copy-paste
>> errors. That is, copying from one place to another place in the document
>> would not be affected by @prefix declaration.
>> 
>> The down-side to this is that all Web page authors do not have access to
>> the root element in a document, which is typically set by the content
>> management system. This would disallow people that know what they're
>> doing from expressing triples in their sub-sections of the document -
>> such as blog articles or comment posts.
>> 
>> PROPOSAL: Limit @prefix declaration to the root element in the document.
>> 
>> -- manu
>> 
>> [1]http://www.w3.org/2010/02/rdfa/meetings/2011-07-14#ISSUE__2d_96__3a__Document_not_ready
>> 
>> -- 
>> Manu Sporny (skype: msporny, twitter: manusporny)
>> President/CEO - Digital Bazaar, Inc.
>> blog: PaySwarm Developer Tools and Demo Released
>> http://digitalbazaar.com/2011/05/05/payswarm-sandbox/
>> 
>> 
> 
> 
> ----
> Ivan Herman, W3C Semantic Web Activity Lead
> Home: http://www.w3.org/People/Ivan/
> mobile: +31-641044153
> PGP Key: http://www.ivan-herman.net/pgpkey.html
> FOAF: http://www.ivan-herman.net/foaf.rdf
> 
> 
> 
> 
> 
> 


----
Ivan Herman, W3C Semantic Web Activity Lead
Home: http://www.w3.org/People/Ivan/
mobile: +31-641044153
PGP Key: http://www.ivan-herman.net/pgpkey.html
FOAF: http://www.ivan-herman.net/foaf.rdf
Received on Wednesday, 10 August 2011 08:02:37 UTC

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