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