72 – Structural pattern matching with dictionaries

72 – Structural pattern matching with dictionaries#

The match statement can be used to match keys and values in a dictionary, effectively matching the structure of the dictionary.

The example below matches all dictionaries that contain a key "user" with a string value and a key "age" with an integer value:

match my_dict:
    case {"user": str(), "age": int()}:
        print("Match!")

Dictionaries that satisfy those restrictions will match, even if they have more key/value pairs, like the dictionary my_dict below:

my_dict = {"user": "John", "age": 47, "children": 2}

The dictionaries below won’t match, respectively because they’re missing the key/value pair for "age" or because the value for "age" doesn’t have the correct type:

my_dict = {"user": "John"}  # Missing `"age"`
my_dict = {"user": "John", "age": "47"}  # `"age"` should be an integer.