Re: Missing use case for supporting ldp:membershipPredicate/Subject

Alexandre Bertails <bertails@w3.org> wrote on 05/29/2013 11:08:12 AM:

> What I meant is that people were already assuming that this was part
> of the spec (it was in the Submission) and that we had to deal with
> it. Most of us (me included) didn't imagined the consequences of
> keeping it and we kept specifying on top of it.

I have no idea at this point what "most of us" think and I would claim 
that if you think you do it's only because you're projecting. ;-)

> ...
> In the light of the recent threads and examples, I'd be interested in
> knowing if people would considerer dropping the support for "existing
> vocabularies".

I agree this is something important we need to find out.

> ...
> For the very same reasons, I wouldn't use any feature that relies on
> the domain model. And with this approach, note that you wouldn't be
> able to distinguish the membership if you had chosen the same
> membershipPredicate, which is another serious drawback.

That's true but why is that a serious drawback? Although less limiting 
than what you're lobbying for the current spec certainly has limits. 
You're not arguing that it should be even more flexible, are you?

> > By the way, I'm wondering whether this isn't really a matter of a
> > missing requirement rather than a missing use case. What I mean is 
that
> > it seems to me that the question at hand is really whether we want to
> > accommodate using existing vocabularies or not.  I think this applies 
to
> > various use cases.
> 
> Existing vocabularies were not thought with LDP in mind as LDP didn't
> exist. So I'm not sure what it means to accommodate the use of these
> existing vocabularies.

I would say that it is because existing vocabularies were not thought with 
LDP in mind that it is important to have this kind of flexibility. The 
current spec allows people to keep using their existing vocabulary. Again, 
there is no denying that this adds complexity. But getting rid of it will 
make it harder for people who already have data in various vocabularies to 
adopt LDP by requiring them to change their data model or transform it on 
the way in and out.

Of course, as always, there is a trade-off. Simplifying the spec makes it 
easier for people who start from scratch. Having more flexibility makes it 
easier for people who already have data they want to expose through LDP.

I think it's important to acknowledge the pros and cons and not discard 
either side.
--
Arnaud  Le Hors - Software Standards Architect - IBM Software Group