Is there a python function like Clojure's get-in?

Question

Is there something equivalent to Clojure's get-in function in Python? It gets the data at the given path in some data structure.

In Clojure it is used like:

(def employee
  {:name "John"
   :details {:email "[email protected]"
             :phone "555-144-300"}})

(get-in employee [:details :email])  ; => "[email protected]"

If translated to Python syntax it would be used like:

dictionary = {'a': {'b': 10}}
get_in(dictionary, ['a', 'b'])  # => 10

This function is used to access arbitrary data points in nestled data structures where the paths are not known at compile time, they are dynamic. More usage examples of get-in can be found on clojuredocs.

Answer 1

You can write:

dictionary.get('details', {}).get('email')

This will safely get the value you need or None, without throwing an exception - just like Clojure's get-in does.

If you need a dedicated function for that, you can write:

def get_in(d, keys):
    if not keys:
        return d
    elif len(keys) == 1:
        return d.get(keys[0])
    else:
        return get_in(d.get(keys[0], {}), keys[1:])