Re: [MISC] Deprecation (was Re: RDF-ISSUE-5 (Graph Literals): Should we define Graph Literal datatypes? [RDF Graphs])

On Mar 7, 2011, at 13:46 , Peter Frederick Patel-Schneider wrote:

> From: Steve Harris <steve.harris@garlik.com>
> Subject: Re: RDF-ISSUE-5 (Graph Literals): Should we define Graph Literal datatypes? [RDF Graphs]
> Date: Sat, 5 Mar 2011 17:03:22 -0600
> 
>> On 2011-03-05, at 14:49, Richard Cyganiak wrote:
>> 
>>> On 4 Mar 2011, at 21:59, RDF Working Group Issue Tracker wrote:
>>>> RDF-ISSUE-5 (Graph Literals): Should we define Graph Literal datatypes? [RDF Graphs]
>>> 
>>> Anyone could trivially define such datatypes. And once that is done, tool vendors could easily add support for them.
>>> 
>>> Given the relative ease of doing this, if there was actual user demand for such datatypes, then surely someone would have already defined them, and they would have seen some adoption.
>>> 
>>> It is my strong belief that standardization efforts should focus on codifying existing practice and not invent new speculative things.
>> 
>> Absolutely.
>> 
>> rdf:XMLLiteral is kind of in this space, and no one really uses that,
>> let alone an RDF version. 
>> 
>> - Steve
> 
> Agreed.
> 
> In fact, in my opinion rdf:XMLLiteral would be a good candidate for
> deprecation.

As I told Steve, Drupal 7 uses it. (I just checked it to be on the safe side.) And, actually, their use case is a fairly compelling one: the generate RDF data for each blog item; the content of the blog is using the RSS vocabulary and what they do is to use the content:encoded property with the body of the blog in XML Literal. Ie, they store the HTML code for the content as part of their RDF data. Which makes sense for applications that want to take this content and display it with formatting intact. 

I would expect that RDFa encoding of blogging applications (wordpress, etc) would use a similar approach. But, regardless of others, the current estimates are that Drupal, as a CMS system, accounts for around half a million web sites, including high profile ones like the White House or the Economist. Eventually, all of these will upgrade to Drupal 7 (which is only a few weeks' old); all the pages will be in RDFa with the structure like above.

So... XML Literals are used. We should not deprecate them.

Ivan



> 
> I wonder whether it would be possible to have someone (not me) do a
> search of extant RDF to see how much use there is of various bits of
> RDF (including various bits of the RDF/XML syntax).
> 
> 
> peter
> 


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