(Swift 3,4,5...) Get the Root of a JSON Document

Demonstrates how to get back to the JSON root object from anywhere in the JSON document. This example uses the following JSON document:

{
  "flower": "tulip",
  "abc":
    {
    "x": [
       { "a" : 1 },
       { "b1" : 100, "b2" : 200 },
       { "c" : 3 }
    ],
    "y": 200,
    "z": 200
    }
}

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func chilkatTest() {
    let json = CkoJsonObject()!

    var jsonStr: String? = "{\"flower\": \"tulip\",\"abc\":{\"x\": [{ \"a\" : 1 },{ \"b1\" : 100, \"b2\" : 200 },{ \"c\" : 3 }],\"y\": 200,\"z\": 200}}"

    var success: Bool = json.load(jsonStr)
    if success != true {
        print("\(json.lastErrorText!)")
        return
    }

    // Get the "abc" object.
    var abcObj: CkoJsonObject? = json.object(of: "abc")
    if json.lastMethodSuccess == false {
        print("abc object not found.")
        return
    }

    // Side note: The JSON of a sub-part of the document can be emitted from any JSON object:
    abcObj.emitCompact = false
    print("\(abcObj!.emit()!)")

    // Navigate to the "x" array
    var xArray: CkoJsonArray? = abcObj!.array(of: "x")
    // We'll skip the null check and assume it's non-null...

    // Navigate to the 2nd object contained within the array.  This contains members b1 and b2
    var bObj: CkoJsonObject? = xArray!.object(at: 1)
    // We'll skip the null check and assume it's non-null...

    // Show that we're at "b1/b2".
    // The value of "b1" should be "200"
    print("b2 = \(bObj!.int(of: "b2").intValue)")

    // Now go back to the JSON doc root:
    var docRoot: CkoJsonObject? = bObj!.getDocRoot()
    // We'll skip the null check and assume it's non-null...

    // Pretty-print the JSON doc from the root to show that this is indeed the root.
    docRoot.emitCompact = false
    print("\(docRoot!.emit()!)")

    docRoot = nil
    bObj = nil
    xArray = nil
    abcObj = nil

}