Nested insertion/creation of dictionary

Question

Given that you have an empty dictionary

data = {}

I have a path and a value

path = "root.sub.item"
value = 12

How could I recursively add objects that do not exist?

def add_value(path, value):
    for part in path.split('.'):
        if not part in data:
            data[part] = {}

The expected output for this would be:

data = {
    'root':{
        'sub':{
            'item': 12
        }
    }
}

Could somebody help out with this or point me in the right direction?
I'm using Python 3.6.

Answer 1

You can use some another kind of solution like recursive defaultdict, as in this answer.

A quick and stupid example about how it can used:

from collections import defaultdict

def func(rdict, path, value):
    items = path.split('.')

    d = rdict[items[0]]

    for item in items[1:-1]:
        d = d[item]

    d[items[-1]] = value

nested_dict = lambda: defaultdict(nested_dict)

result = nested_dict()

func(result, 'root.sub.item', 12)
func(result, 'root.moon.value', 1)

assert result['root']['sub']['item'] == 12
assert result['root']['moon']['value'] == 1
assert result['root']['moon']['noop'] != 0