Shape Expressions (ShEx) ^[2] is a data modelling language for validating and describing a Resource Description Framework (RDF).

It was proposed at the 2012 RDF Validation Workshop^[3] as a high-level, concise language for RDF validation.

The shapes can be defined in a human-friendly compact syntax called ShExC or using any RDF serialization formats like JSON-LD or Turtle.

ShEx expressions can be used both to describe RDF and to automatically check the conformance of RDF data. The syntax of ShEx is similar to Turtle and SPARQL while the semantics is inspired by regular expression languages like RelaxNG.

PREFIX :       <http://example.org/>
PREFIX schema: <http://schema.org/>
PREFIX xsd:  <http://www.w3.org/2001/XMLSchema#>

:Person {
 schema:name  xsd:string   ;
 schema:knows @:Person   * ;
}

The previous example declares that nodes conforming to shape Person must have one property schema:name with a string value and zero or more properties schema:knows whose values must conform with shape Person.

• ShExSimple: Online demo based on shex.js
• rdfshape: online demo based on shaclex Archived 2018-11-19 at the Wayback Machine