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

(why is this discussed on "comments"?)

JSON-LD does not allowed the full range of "generalized RDF".

	Andy

On 02/08/13 16:22, David Wood wrote:
> Yes, I concur with Sandro.  The RDF WG inserted the "generalized RDF"
> description for a good reason.  It is there to allow for alignment
> with JSON-LD and any future implementations or formats that cannot,
> for good technical reasons, limit their possible parsings to standard
> RDF.
>
> That does not mean, however, that we should encourage "generalized
> RDF" at any point.  Its use should be strongly discouraged in
> implementations and where that is impossible, as with JSON-LD, then
> its /social/ use should be strongly discouraged, as with JSON-LD.
> Hence, I think we should put in the stronger wording but leave the
> concept in place.
>
> Chair and editor hats simultaneously "on" and "off".  Take that,
> Erwin Schrödinger!
>
> Regards, Dave -- http://about.me/david_wood
>
>
>
> On Aug 2, 2013, at 09:15, Sandro Hawke <sandro@w3.org> wrote:
>
>> 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 16:42:42 UTC