{
  "source_variable_1": {
    "type": "variable",
    "default": "val1",
    "properties": [
      {
        "type": "type",
        "name": "string"
      },
      {
        "type": "mode",
        "name": "standard"
      },
      {
        "type": "property",
        "name": "mandatory"
      }
    ],
    "paths": [
      "source_variable_1"
    ],
    "names": [
      "source_variable_1"
    ],
    "descriptions": [
      "The first source variable."
    ]
  },
  "source_variable_2": {
    "type": "variable",
    "default": "val2",
    "properties": [
      {
        "type": "type",
        "name": "string"
      },
      {
        "type": "mode",
        "name": "standard"
      },
      {
        "type": "property",
        "name": "mandatory"
      }
    ],
    "paths": [
      "source_variable_2"
    ],
    "names": [
      "source_variable_2"
    ],
    "descriptions": [
      "The second source variable."
    ]
  },
  "my_variable": {
    "type": "variable",
    "default": "val1",
    "properties": [
      {
        "type": "type",
        "name": "choice"
      },
      {
        "type": "mode",
        "name": "standard"
      },
      {
        "type": "property",
        "name": "mandatory"
      }
    ],
    "choices": [
      "the value of the variable \"source_variable_1\".",
      "the value of the variable \"source_variable_2\"."
    ],
    "paths": [
      "my_variable"
    ],
    "names": [
      "my_variable"
    ],
    "descriptions": [
      "A variable."
    ]
  }
}