JSON as Trees

The crucial theoretical concept to grok for JEQUEL is the fact that all JSONs are treated like trees.

Eg this JSON:

[
	{
		k1: '1', k2: 'somedata', k3: [
			{id: 'a' e2a1: 'something a'}
			{id: 'b' e2a1: 'something b'}
			{id: 'c' e2a1: 'something c'}
		]
	},
	{
		k1: '2' k2: 'anothersomedata' k3: [
			{id: 'i' 	e2a1: 'something i'}
			{id: 'ii' 	e2a1: 'something ii'}
			{id: 'iii' 	e2a1: 'something iii'}
			{id: 'iv' 	e2a1: 'something iv'}
		]
	}
]

Can be represented as a tree with the following properties:

1. Arrays can be thought of as Objects having numeric keys.
2. A variable is a node.
3. A key is an edge.
4. Only String, Boolean, Number, Empty Array and Empty Object can be leaf nodes.

Graphically,

JSON Pointer Notation

Any position in this tree can be specified with a JSON Pointer. For details consult RFC6901.

JSON Pointer extension.

Taking a cue from JSONPath, we have built a couple of extensions on JSON Pointer.

1. The wildcard * is used to match all keys.
2. The wildcard $ is used to represent the root node of the JSON tree.