Re: ldp-ISSUE-73 (rdf:member): LDPCs to list all their rdf:member [Linked Data Platform core]

Henry Story <henry.story@bblfish.net> wrote on 05/29/2013 09:06:01 AM:

> ...
> The intent as you can see from the SPARQL example is that one use 
> rdf:member as the relation.
> I'll edit it to 
> 
> [[
> An LDPC MUST list all the resources created in it as a relation 
> between the container and the created LDPR via
> the rdf:member relation.
> ]]

This reads as if this only concerns resources that were created via the 
container (presumably using POST) and doesn't necessarily apply to a 
member resource that would be added via PATCH. I don't think that's what 
you mean, is it?

> ...
> If you look further in Model 2, which he put together with you,
> you'll see that the </app/BugTracker/products/> container 
> contains no members:
> 
> ~~~~~~~~~~~~
> <http://example.org> a ldp:Container;
>  ldp:membershipSubject <http://example.org/app/BugTracker>;
>  ldp:membershipPredicate bt:tracksProduct .
> ~~~~~~~~~~~~
> 
> But that one is meant to guess from looking at the BugTracker resource 
that
> members were created.
> 
> ~~~~~~~~~~~~
> <http://example.org/app/BugTracker> a bt:BugTracker;
>  tracksProduct </app/BugTracker/products/ProductA> ,
>            </app/BugTracker/products/ProductB> ;
>         hasBug </app/BugTracker/bugs/1> .
> ~~~~~~~~~~~~

Saying that the container contains no members is incorrect. And there is 
no guessing involved to find otherwise.

The membershipSubject of the container tells you the subject of the 
triples you need to look for and its membershipPredicate tells you the 
predicate of the triples you need to look for.

So to find the members of the container you need to look for triples of 
the form:
membershipSubject membershipPredicate member

Where membershipSubject membershipPredicate have been substituted to their 
appropriate value.

The triples that match this pattern tell you which members the container 
contains.

> 
> Now issue-73 is not arguing that one should remove those 
rdf:membershipXXX
> relations. (Though they are seriously misleading.) I'll open an issue on
> the misleading nameing of rdf:membershipXXX perhaps, so that these 
issues
> remain clearly seperated.

That you think the names are misleading only shows that so far we have 
failed to properly convey what they are meant for.

This again makes me wonder how much of this discussion is due to 
misunderstanding. If anything this shows that we at least need to clarify 
the intent!

Thanks.
--
Arnaud  Le Hors - Software Standards Architect - IBM Software Group