Re: Text about SPARQL-star built-in functions ready

On 03/03/2021 17:32, Gregg Kellogg wrote:
> On Mar 3, 2021, at 3:25 AM, Pierre-Antoine Champin 
> <pierre-antoine.champin@ercim.eu> wrote:
>>
>> 
>> On 02/03/2021 21:34, Gregg Kellogg wrote:
>>>> On Mar 2, 2021, at 12:09 PM, James Anderson 
>>>> <anderson.james.1955@gmail.com 
>>>> <mailto:anderson.james.1955@gmail.com>> wrote:
>>>>
>>>> good evening;
>>>>
>>>>> On 2021-03-02, at 18:56:40, Olaf Hartig <olaf.hartig@liu.se 
>>>>> <mailto:olaf.hartig@liu.se>> wrote:
>>>>>
>>>>> Hi all,
>>>>>
>>>>> I have implemented the proposal [1] to add the five new built-in 
>>>>> functions to
>>>>> the spec. See the following PR
>>>>>
>>>>> https://github.com/w3c/rdf-star/pull/118 
>>>>> <https://github.com/w3c/rdf-star/pull/118>
>>>>>
>>>>> For your convenience, here is the link to the preview:
>>>>>
>>>>> https://pr-preview.s3.amazonaws.com/w3c/rdf-star/pull/118.html
>>>>>
>>>>> The changes are in Section 4.2 (SPARQL-star Grammar) and in the 
>>>>> new Section
>>>>> 4.4 (Function Definitions).
>>>>>
>>>>> As agreed during our telco last Friday, I will leave this PR open 
>>>>> for three
>>>>> days so that your can take a look at it and raise concerns (if 
>>>>> any). Unless
>>>>> anyone brings forward reasons that this PR should not be merged, I 
>>>>> will merge
>>>>> it on Friday afternoon (CET).
>>>>
>>>> i raise the concern, that the approach needs to comprehend quads 
>>>> before it will be usable.
>>>
>>> I think this comment is more general than the specific functions 
>>> added. It would be useful to have some examples that use various 
>>> combinations of embedded triples, annotations, and these functions 
>>> within named graphs.
>> +1 to that
>>>
>>> Eventually, we need to understand the implications for N-Quads and TriG.
>>
>> My feeling is that they are pretty much covered by the definition of 
>> RDF-star dataset [1].
>>
>>> (...) Basically, embedded triples go in the default graph, 
>>> annotations stay in the graph in which they’re defined.
>>
>> I strongly disagree with the first part of that sentence.
>>
> I mis-spoke. What I intended to say is that embedded triples, 
> regardless of where they appear, are the same triple and have no named 
> graph component. They don’t. “go” anywhere.
>
> The annotation syntax asserts a triple within whatever graph contains 
> it, and describes other triples, also in that graph, whose subject is 
> an embedded triple.
Then we agree :)
>
> The point is that embedded triples can’t be thought of as having a 
> named graph component.

or having /any/ graph component at all (not even the default graph).

They are not quads, they are just triples.

>> Embedded triples are terms, so they don't go in any graph (just like 
>> an IRI or a literal does not go in or belong to any graph). If they 
>> go anywhere, that is in another triple (as their subject or object).
>>
>> In what was previously known as PG mode, the mention of an embedded 
>> triples caused that triple to be also asserted, and then the question 
>> would raise of where this assertion was added. But in the current 
>> spec, this question is moot.
>>
>> PA
>>
>> [1] https://w3c.github.io/rdf-star/cg-spec/editors_draft.html#dfn-dataset
>>
>>