Re: comments on SHACL Core Abstract Syntax and Semantics

Thank you, Peter, these are great comments. We'll incorporate as many as 
we can into the next version of the document.

I do have a question about your use of the term "semantics" because it 
may be different from mine. By "semantics" do you mean the 
English-language explanations of the syntax? And if so, does that also 
include the examples?

Thanks again,
kc

On 8/26/16 11:09 AM, Peter F. Patel-Schneider wrote:
> Some comments on SHACL Core Abstract Syntax and Semantics first public
> working draft 25 August 2016 at https://www.w3.org/TR/shacl-abstract-syntax/
>
>
> There is a discrepancy between the title and abstract of the document.  The
> title includes semantics but the abstract only talks about syntax.  The
> document should be clear at the beginning about what it covers.
>
> The body of the document does talk about the semantics of SHACL.  There is
> already a semantics provided for SHACL in https://www.w3.org/TR/shacl/.
> There does not appear to be any reason to have two different documents that
> provide a semantics for SHACL, even with one of them being non-normative.
> As there is no reason for a second version of the semantics of SHACL it
> needs to be removed from this document.
>
> The document appears to provide an abstract syntax for SHACL.  The abstract
> and title say "core SHACL" but there is no discussion in the body of the
> document as to just what is being covered.  If the document is just covering
> the core of SHACL it needs to qualify what it is doing throughout the body
> of the document.
>
> The document does not even cover all of the core of SHACL.  For example, it
> does not provide for severities or any of the non-validating aspects of
> SHACL shapes.  This needs to be remedied or explained.
>
> The document uses "SHACL instance graph".  This is probably referring to a
> shapes graph and thus probably needs to be changed.  Instance graphs,
> however, contain schemas, which are not defined for SHACL.
>
> The document uses RDF Semantics as its source of definitions for some RDF
> notation.  It would be better to reference RDF 1.1 Concepts and Abstract
> Syntax where possible.
>
>
> I think that the document in its current form has negative utility.  The
> abstract syntax does not correspond to any coherent part of SHCL.  The
> semantics is just going to be a competitor to the informal and formal
> semantics in https://www.w3.org/TR/shacl/.  If the semantics stuff was
> removed and the abstract syntax actually corrsponded to the SHACL core
> syntax then there might be some small utility for the document.
>
>
> Peter F. Patel-Schneider
> Nuance Communications
>
>
>

-- 
Karen Coyle
kcoyle@kcoyle.net http://kcoyle.net
m: 1-510-435-8234
skype: kcoylenet/+1-510-984-3600

Received on Saturday, 27 August 2016 15:47:11 UTC