{
  "$id": "https://schemas.opendd.eu/xtdsymbol.1.schema.json",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "title": "xtd Symbol Schema",
  "description": "According to SS-EN ISO 12006-3:2022",
  "type": "object",
  "allOf": [
    {
      "$ref": "/xtdroot.1.schema.json"
    },
    {
      "$ref": "#/$defs/xtdSymbol"
    }
  ],
  "$defs": {
    "xtdSymbol": {
      "type": "object",
      "properties": {
        "Symbol": {
          "description": "Unicode symbol of the property",
          "oneOf": [
            {
              "$ref": "/xtdtext.1.schema.json"
            },
            {
              "$ref": "/opendd-entityref.1.schema.json"
            }
          ]
        },
        "Subject": {
          "description": "Subject used to attach a specific “context” for using the symbol of a property.",
          "$ref": "/opendd-entityref.1.schema.json"
        }
      },
      "required": [
        "Symbol"
      ]
    }
  },
  "unevaluatedProperties": false
}