Re: What we voted on at the f2f

I agree with Karen that this is worth some further clarification given the 
current contention over the role of SPARQL in the spec and I agree with 
Irene that it's not easy to avoid the confusion around what SPARQL 
definitions are really meant to convey.

One thing I wonder is whether the fact that the semantics of the higher 
level constructs in Holger's proposal are actually based on SPIN templates 
rather than plain SPARQL isn't adding to the confusion and negative 
reaction by some.
--
Arnaud  Le Hors - Senior Technical Staff Member, Open Web Technologies - 
IBM Software Group


Irene Polikoff <irene@topquadrant.com> wrote on 03/24/2015 10:18:04 AM:

> From: Irene Polikoff <irene@topquadrant.com>
> To: <kcoyle@kcoyle.net>, "public-data-shapes-wg@w3.org" <public-
> data-shapes-wg@w3.org>
> Date: 03/24/2015 10:28 AM
> Subject: Re: What we voted on at the f2f
> 
> <I took this to mean that the specification
> would use SPARQL as the "abstract language" to define the meaning of the
> SHACL vocabulary.>
> 
> I believe this is what is being followed in the spec.
> 
> <In fact, I don't think that we made a decision as to the
> implementation of SHACL or to any stated relationship between SHACL as a
> specification and any particular implementations of SHACL.>
> 
> I don¹t believe it would be within the remit of the WG to mandate a
> particular way to implement SHACL. WG could only define what must happen
> given certain data and certain SHACL constraint - irrespective of how
> implementers accomplish this.
> 
> However, of course, once one defines the meaning of SHACL vocabulary 
using
> SPARQL, they are half way (not all the way though) to the implementation
> because SPARQL is executable. Thus, the view that SHACL specification
> describes SPARQL-based implementation does have some grounds. It is not 
a
> goal in itself, but a by-product of using SPARQL to define the meaning.
> 
> Irene
> 
> On 3/24/15, 1:04 PM, "Karen Coyle" <kcoyle@kcoyle.net> wrote:
> 
> >We clearly have different interpretations of the meaning of our vote at
> >the face-to-face, which was:
> >
> >RESOLUTION: Define semantics using SPARQL as much as possible
> >
> >My view may be naive, but I took this to mean that the specification
> >would use SPARQL as the "abstract language" to define the meaning of 
the
> >SHACL vocabulary. The minutes of the f2f show that the vote was taken 
in
> >the context of a discussion of the "normative expression" for SHACL, 
and
> >a "formalism." Others suggested included the use of Z as a formalism,
> >but that didn't get much traction.
> >
> >There is another view, which is that the SHACL specification describes 
a
> >SPARQL implementation, although other implementations are not excluded.
> >This view treats the specification as a description of the SPARQL
> >implementation, referring to it as a "built-in" language for SHACL. In
> >this view, there is no "abstract language" formally defining SHACL.
> >
> >I see a rather large gap between using SPARQL as a formalism in the
> >specification, and assuming that the SHACL standard is a SPARQL
> >implementation. In fact, I don't think that we made a decision as to 
the
> >implementation of SHACL or to any stated relationship between SHACL as 
a
> >specification and any particular implementations of SHACL.
> >
> >However, as I said, my view may be naive, but I wonder if we can't
> >clarify at least what we voted on at the f2f, since we seem to be
> >intoning that vote in our discussion here with at least two different
> >meanings.
> >
> >kc
> >-- 
> >Karen Coyle
> >kcoyle@kcoyle.net http://kcoyle.net
> >m: 1-510-435-8234
> >skype: kcoylenet/+1-510-984-3600
> >
> 
> 
>