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ndict-tools

In standard Python, dictionaries within dictionaries are possible, creating nested data structures. However, while this functionality exists, Python does not offer native features to easily search and manage keys and values within complex nested dictionaries.

My research and testing of libraries dedicated to managing nested dictionaries led me to several solutions, but none fully met my expectations. The module I found that came closest was one from 2015, available on PyPI, but it does not provide a complete architecture for managing "nested dictionary objects" in a smooth and robust way.

This motivated me to redevelop such a module, offering a more complete and intuitive way to handle nested dictionaries. This new module makes it easier to manipulate, search, and manage keys and values in complex data structures by providing tools dedicated to this specific task.

What is a Nested Dictionary?

A nested dictionary is simply a dictionary where the values themselves are dictionaries. This allows for the creation of richer, hierarchical data structures where each "node" in the structure can hold additional information in the form of dictionaries, making it easier to model complex data in an organized and accessible way.

Using Nested Keys and Managing Hierarchies in Dictionaries

Keys of Different Types and Using Lists for Hierarchical Keys

Just like with standard dictionaries in Python, the keys in a nested dictionary must be hashable. This means you can use types such as numbers, strings, or even tuples as keys. However, lists are not hashable and cannot be used directly as keys.

Accessing Nested Values

Nested dictionaries allow you to structure your data over multiple levels. For example, to access a value in a nested dictionary, you can use a sequence of keys that represents each level of the hierarchy.

Using simple, non-nested lists is the way used to represent nested keys.

Nested Access Example

The following two expressions are equivalent for accessing a value in a nested dictionary:

dictionary[[1, "a", (2, 3)]]   # is equivalent to
dictionary[1]["a"][(2, 3)]

Installation

pip install ndict-tools

Documentation

Full documentation is available at ndict-tools.readthedocs.io.

Contributing

See CONTRIBUTING.md for setup instructions and contribution guidelines.

License

This project is licensed under the CeCILL-C Free Software License.