{
  "@context": "http://www.w3.org/ns/shex.jsonld",
  "type": "Schema",
  "shapes": [
    { "type": "ShapeDecl",
    "id": "http://a.example/S1",
    "shapeExpr": {
      "type": "Shape",
      "expression": {
        "type": "TripleConstraint",
        "predicate": "http://a.example/p1",
        "valueExpr": {
          "type": "ShapeOr",
          "shapeExprs": [
            {
              "type": "ShapeNot",
              "shapeExpr": "http://a.example/S2"
            },
            {
              "type": "Shape",
              "expression": {
                "type": "TripleConstraint",
                "predicate": "http://a.example/p2"
              }
            }
          ]
        }
      }
    } },
    { "type": "ShapeDecl",
    "id": "http://a.example/S2",
    "shapeExpr": {
      "type": "Shape",
      "expression": {
        "type": "TripleConstraint",
        "predicate": "http://a.example/p3"
      }
    } }
  ]
}