Re: @href and @src in RDFa 1.1 Core (Re: Editor's Drafts Updated)

On Apr 1, 2010, at 20:09 , Shane McCarron wrote:

> 
> 
> Ivan Herman wrote:
>> The current RDFa 1.1 Core still lists @href and @src as part of the core RDFa vocabulary. I am not sure that is correct. @resource and @about covers all our needs, and the only reason we have them in RDFa 1.0 is to abide to HTML authoring.
>>  
> I understand and I disagree.  I spent a lot of time thinking about this and discussing it with Manu offline. 
> As written, the document indicates there are attributes that might not be present in some host languages.  It also says that when they are present, they have the semantics indicated.  I feel this is the cleanest way to ensure that when href, src, rel, rev, profile, etc. are indeed available, they work the way we need them to.  I have tried to cover this in the section on Host Language conformance and in the Processing Rules.  It might be good to note which attributes are mandatory for host languages.  I will do that.


I guess this is longer discussion because I am still uneasy. There is nothing that prevents another XML language to use the attribute @src for something completely different for which the RDFa semantics would be strange and unfitting. Even if some accompanying text would say "yes, we have @src, and we also use RDFa, but our @src is not like RDFa's @src, so do not use it that way" would be terribly confusing.

RDFa does not make use of xlink:href in SVG either. Of course, SVG could define that, but it has not. So there is an asymmetry already...


My view at the moment is:

- @href/@src would not be in core
- @href/@src would be allowed in XHTML and HTML5
- for other languages we could say that it is of course possible to do what HTML does, but we discourage that... 

Ivan


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Ivan Herman, W3C Semantic Web Activity Lead
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