Re: shapes-ISSUE-52 (labra): Define an Abstract Syntax for SHACL [SHACL Spec]

Labra,

I am not opposed to an abstract syntax. However, that is not the only
way to define the high-level language. I'd prefer the high-level
language (and the compact syntax) to be completely defined in terms of
the core language, which can make use of SPARQL.

That does leave some aspects of the core language to specify since it
won't all be expressible in SPARQL. However, that doesn't necessarily
mean we need to introduce an abstract syntax. We already have one
syntax (RDF). Rather than introduce another syntax, we should focus on
semantics. We have several choices, i.e. operational, denotational, or
axiomatic. I think it will be easiest to give SHACL a denotational
semantics in terms of the domain objects such as RDF graphs and
constraints.

-- Arthur

On Sat, May 23, 2015 at 1:23 AM, RDF Data Shapes Working Group Issue
Tracker <sysbot+tracker@w3.org> wrote:
> shapes-ISSUE-52 (labra): Define an Abstract Syntax for SHACL [SHACL Spec]
>
> http://www.w3.org/2014/data-shapes/track/issues/52
>
> Raised by: Jose Emilio Labra Gayo
> On product: SHACL Spec
>
> One of the already approved requirements is that SHACL should be a higher
> level language.
>
> To do that, most languages define an abstract syntax
> or functional specification which describes the main constructs of the
> language without depending on any concrete syntax.
>
> Most language specifications are defined based on an abstract syntax. For
> example:
>
> RDF Abstract Syntax and concepts (http://www.w3.org/TR/rdf11-concepts/)
>
> SPARQL (http://www.w3.org/TR/sparql11-query/#sparqlDefinition)
>
> OWL (http://www.w3.org/TR/2012/REC-owl2-syntax-20121211/)
>
> There are several advantages when defining an abstract syntax for describing
> a language like:
>
> -Separation of concerns: it is possible to identify which are the language constructs and separate them from the semantic formalism in which they are defined
>
> - Allowing the language designers to concentrate on the language concepts instead of syntactic details
>
> - Identification of possible redundant constructs or constructs that can be added
>
> - Mapping between one concrete syntax to another concrete syntax. In the last VF2F3 meeting there seemed to be some consensus on defining a compact syntax for SHACL. In order to do so, it will be helpful to define first that abstract syntax so we could later map from that abstract syntax to the concrete syntax.
>
> This issue is only about defining an abstract syntax for SHACL.
>
> Having such an abstract syntax does not imply any compromise about the formalism used for the semantic definition which could be either by mappings to SPARQL or by other formalisms.
>
>
>
>
>
>
>
>
>

Received on Wednesday, 10 June 2015 22:39:55 UTC