{
  "@context": "http://www.w3.org/ns/shex.jsonld",
  "type": "Schema",
  "shapes": [
    { "type": "ShapeDecl",
    "id": "http://a.example/S1",
    "shapeExpr": {
      "type": "ShapeNot",
      "shapeExpr": {
        "type": "Shape",
        "expression": {
          "type": "TripleConstraint",
          "predicate": "http://a.example/p1",
          "valueExpr": {
            "type": "ShapeNot",
            "shapeExpr": {
              "type": "NodeConstraint",
              "values": [
                "http://a.example/v1",
                "http://a.example/v2"
              ]
            }
          }
        }
      }
    } }
  ]
}