Re: RDFa Default Profile Management

Toby,

the issue seems to be (if I understand well) that if an implementation is unwise in its choice of additional prefixes and, as this seems to be the case here, it defines prefixes for strings that may also be used as URI schemes, then there is a problem. While I fully agree this is true, I do not think this is something the RDFa Rec has to deal with... It is what I regard an implementation bug.

Ivan

On Feb 8, 2011, at 23:39 , Toby Inkster wrote:

> On Tue, 8 Feb 2011 09:38:22 +0100
> Ivan Herman <ivan@w3.org> wrote:
> 
>> On Feb 8, 2011, at 08:17 , Toby Inkster wrote:
>> 
>>> If a consumer includes a default prefix mapping of something like:
>>> 
>>> 	"about" => "http://example.com/vocab/about#"
>>> 
>>> Then it will hit a compliance issue as soon as it sees:
>>> 
>>> 	<span rel="next" resource="about:blank">this is the last  
>>> 	page</span>   
>> 
>> Why? I do not understand...
> 
> OK, we're assuming that the consumer is including a mapping of:
> 
> 	"about" => "http://example.com/vocab/about#"
> 
> which is not in the host language default profile, and not specified in
> the document. The intention of the document is to create the following
> triple:
> 
> 	<> xhv:next <about:blank> .
> 
> And that's what a conformant RDFa implementation should produce.
> However, if the implementation has that additional default mapping,
> then it will produce:
> 
> 	<> xhv:next <http://example.com/vocab/about#blank> .
> 
> Nathan wrote:
> 
>> about: isn't an IANA registered URI scheme
> 
> Not yet, but it's an Internet Draft expected to become an RFC (and thus
> a registered URI scheme).
> 
> Besides which, we don't specify that URI schemes used in RDFa must be
> registered. The following works in Turtle and I wouldn't want it to
> break in RDFa:
> 
> 	<#i> foaf:account <irc://irc.freenode.net/tobyink,isnick> .
> 
> -- 
> Toby A Inkster
> <mailto:mail@tobyinkster.co.uk>
> <http://tobyinkster.co.uk>
> 


----
Ivan Herman, W3C Semantic Web Activity Lead
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