(Tcl) 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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load ./chilkat.dll

set json [new_CkJsonObject]

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

set success [CkJsonObject_Load $json $jsonStr]
if {$success != 1} then {
    puts [CkJsonObject_lastErrorText $json]
    delete_CkJsonObject $json
    exit
}

# Get the "abc" object.
# abcObj is a CkJsonObject
set abcObj [CkJsonObject_ObjectOf $json "abc"]
if {[CkJsonObject_get_LastMethodSuccess $json] == 0} then {
    puts "abc object not found."
    delete_CkJsonObject $json
    exit
}

# Side note: The JSON of a sub-part of the document can be emitted from any JSON object:
CkJsonObject_put_EmitCompact $abcObj 0
puts [CkJsonObject_emit $abcObj]

# Navigate to the "x" array
# xArray is a CkJsonArray
set xArray [CkJsonObject_ArrayOf $abcObj "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
# bObj is a CkJsonObject
set bObj [CkJsonArray_ObjectAt $xArray 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"
puts "b2 = [CkJsonObject_IntOf $bObj b2]"

# Now go back to the JSON doc root:
# docRoot is a CkJsonObject
set docRoot [CkJsonObject_GetDocRoot $bObj]
# 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.
CkJsonObject_put_EmitCompact $docRoot 0
puts [CkJsonObject_emit $docRoot]

delete_CkJsonObject $docRoot

delete_CkJsonObject $bObj

delete_CkJsonArray $xArray

delete_CkJsonObject $abcObj


delete_CkJsonObject $json