Re: More clearly warn that "generalized RDF" is non-standard

Speaking just for myself, I think this is going too far.   I think it 
does a service to the community to define the term "generalized RDF" in 
RDF concepts, since (1) it's used in at least two of our specs which 
we'd rather not have depend on each other (JSON-LD and RDF Semantics), 
and (2) it's something people come up with on their own anyway, and this 
way we tag the discussions about it.  It's hard to evolve or extend a 
standard  interchange format, but the best hope for doing so is to have 
everyone who wants to add some feature add it in the same way and talk 
about it the same way.   By defining "generalized RDF" in RDF Concepts, 
I think we're doing that.

All that said, I think it would be a good idea to add something like the 
warning note you propose, and perhaps some of the explanation I just 
provided.   That is, roughly: Generalized RDF is not standard RDF, but 
it can be useful and is reasonable to use among systems which have all 
agreed to use it.  If you try to send it to systems which have not 
agreed to use it, it won't work.

        -- Sandro

On 08/01/2013 04:17 PM, David Booth wrote:
> I've been thinking further about this, and I have another more radical 
> suggestion.
>
> It seems to me that including even an informative definition of 
> "generalized RDF" in the RDF spec substantially increases the risk 
> that someone may mistakenly believe that "generalized RDF" is some 
> form of standard RDF, when it is not. It is an extension of RDF that 
> does not conform to the RDF standard. Hence it is all the more 
> important to visibly warn readers about the use of generalized RDF.
>
> Actually, the more I think about it the more I am convinced that the 
> inclusion of the definition of "generalized RDF" in the RDF spec **at 
> all** is a big mistake, because it substantially increases the risk 
> that someone may mistakenly believe that "generalized RDF" is some 
> form of standard RDF, when it is not.
>
> Thus, my second suggestion is to entirely remove the definitions of 
> generalized RDF triple, graph and dataset from the RDF Concepts document
> https://dvcs.w3.org/hg/rdf/raw-file/default/rdf-concepts/index.html#section-generalized-rdf 
>
>
> If the RDF Semantics document needs to define the notion of 
> generalized RDF to simplify the semantic rules, then I guess a 
> definition could be included in that document, *with* a big fat 
> warning saying that this definition is included only to simplify the 
> specification of the formal semantics, and does not constitute a part 
> of the RDF standard.
>
> David
>
>
> On 08/01/2013 11:20 AM, David Wood wrote:
>> Hi David,
>>
>> I acknowledge your comment and your concern.  I *personally* agree with
> > you that we need to carefully word this section of RDF Concepts.
>>
>> The next RDF WG meeting that I will be able to attend is 21 August,
> > so I will put this on the agenda for that meeting.
>>
>> Regards,
>> Dave
>> -- 
>> http://about.me/david_wood
>>
>>
>>
>> On Aug 1, 2013, at 10:28, David Booth <david@dbooth.org> wrote:
>>
>>> Section 7 defines the notion of "generalized RDF", triples and 
>>> datasets, but does not adequately warn that "generalized RDF" is 
>>> non-standard. Case in point: this has already led to some discussion 
>>> in the JSON-LD group about whether "generalized RDF" is a form of 
>>> standard RDF.
>>>
>>> I suggest rewording section 7 to the following, using a "NOTE" 
>>> call-out:
>>> [[
>>>     <p>It is sometimes convenient to loosen the requirements
>>>     on <a>RDF triple</a>s.  For example, the completeness
>>>     of the RDFS entailment rules is easier to show with a
>>>     generalization of RDF triples.   </p>
>>>
>>>     <p>A <dfn>generalized RDF triple</dfn> is an RDF triple
>>>     generalized so that subjects, predicates, and objects
>>>     are all allowed to be IRIs, blank nodes, or literals.
>>>     A <dfn>generalized RDF graph</dfn> is an RDF graph of
>>>     generalized RDF triples, i.e., a set of generalized RDF
>>>     triples.  A <dfn>generalized RDF dataset</dfn> is an RDF
>>>     dataset of generalized RDF graphs where graph labels can
>>>     be IRIs, blank nodes, or literals.</p>
>>>
>>>     <p class="note" id="note-generalized-rdf"> Any users of
>>>     generalized RDF triples, graphs or datasets need to be
>>>     aware that these notions are non-standard extensions of
>>>     RDF and their use may cause interoperability problems.
>>>     There is no requirement on the part of any RDF tool to
>>>     accept, process, or produce anything beyond standard RDF
>>>     triples, graphs, and datasets. </p>
>>> ]]
>>>
>>> Thanks,
>>> David
>>>
>>
>
>

Received on Friday, 2 August 2013 13:16:07 UTC