Re: ShEx 0.1.0 gem

I knew if I kept looking forlornly in the direction of RDF.rb, a ShEx
implementation would appear. Excellent work, many thanks.

Judson

On Mon, Dec 12, 2016 at 9:26 AM Aymeric Brisse <aymeric.brisse@gmail.com>
wrote:

> That's great news Gregg! I am definitely gonna use that gem.
>
> On Mon, Dec 12, 2016 at 1:22 AM, Gregg Kellogg <gregg@greggkellogg.net>
> wrote:
>
> I’ve just released version 0.1.0 of the shex gem [1], which implements the
> latest Shape Expressions (ShEx) community specification [2].
>
> Shape Expressions can be used to validate nodes within RDF graphs using
> schema language for describing various restrictions on nodes within a
> graph. For example, the project DOAP description [3], can be validated
> using the following ShEX schema [4]:
>
> PREFIX doap:  <http://usefulinc.com/ns/doap#>
> PREFIX dc:    <http://purl.org/dc/terms/>
> <TestShape> EXTRA a {
>   a [doap:Project];
>
>   # May have either or both of doap:name/doap:description or
> dc:title/dc:description
>   ( doap:name Literal;
>     doap:description Literal
>   | dc:title Literal;
>     dc:description Literal)+;
>
>   # Good idea to use a category for what the project relates to
>   doap:category IRI*;
>
>   # There must be at least one developer
>   doap:developer  IRI+;
>
>   # For our purposes, it MUST implement the ShEx specification.
>   doap:implements [<https://shexspec.github.io/spec/>]
> }
>
> The project is UNLICENCED to the Public Domain, available on GitHub [5].
>
> The gem implements an LL(1) parser to generate an executable algebra,
> similar to that used for SPARQL and LD Patch gems. For example, the
> proceeding ShExC can be expressed in the following S-Expression:
>
> (schema
>  (prefix (("doap" <http://usefulinc.com/ns/doap#>) ("dc" <
> http://purl.org/dc/terms/>)))
>  (shapes
>   ((<TestShape> (shape
>      (eachOf
>       (tripleConstraint a
>        (nodeConstraint (value <http://usefulinc.com/ns/doap#Project>)))
>       (oneOf
>        (eachOf
>         (tripleConstraint <http://usefulinc.com/ns/doap#name>
>          (nodeConstraint literal))
>         (tripleConstraint <http://usefulinc.com/ns/doap#description>
>          (nodeConstraint literal)) )
>        (eachOf
>         (tripleConstraint <http://purl.org/dc/terms/title>
>          (nodeConstraint literal))
>         (tripleConstraint <http://purl.org/dc/terms/description>
>          (nodeConstraint literal)))
>        (min 1) (max "*"))
>       (tripleConstraint <http://usefulinc.com/ns/doap#category>
>        (nodeConstraint iri)
>        (min 0) (max "*"))
>       (tripleConstraint <http://usefulinc.com/ns/doap#developer>
>        (nodeConstraint iri)
>        (min 1) (max "*"))
>       (tripleConstraint <http://usefulinc.com/ns/doap#implements>
>        (nodeConstraint (value <https://shexspec.github.io/spec/>))) )
>      (extra a))))))
>
> Gregg Kellogg
> gregg@greggkellogg.net
>
> [1] https://rubygems.org/gems/shex
> [2] https://shexspec.github.io/spec/
> [3] https://github.com/ruby-rdf/shex/blob/develop/etc/doap.ttl
> [4] https://github.com/ruby-rdf/shex/blob/develop/etc/doap.shex
> [5] https://github.com/ruby-rdf/shex
>
>
>
>