yv

Simple utils to get stuff out of Mappings (dict-like objects).

To install: pip install yv

Overview

The yv package provides a collection of utilities designed to facilitate the extraction, manipulation, and querying of data from dictionary-like objects in Python. These utilities are particularly useful when dealing with nested or complex data structures commonly encountered in data processing tasks.

Features

• Key Chain Extraction: Retrieve values from a dictionary using a list of potential keys.
• Subdictionary Access: Enhanced dictionary class allowing for easy subdictionary creation and batch key retrieval.
• MongoDB-style Querying: Filter dictionary items using MongoDB-like query language.
• Nested Key Paths: Functions to handle nested dictionary paths for setting and getting values.
• Utility Functions: Includes various utility functions for dictionary manipulation and querying.

Usage Examples

Key Chain Extraction

Retrieve values from a dictionary using a list of potential keys, with the first found key's value being returned.

from yv import key_chain

d = {'a': 1, 'b': 2, 'c': 3}
result = key_chain(d, 'x', 'c', 'b')  # Returns 3

Subdictionary Access

Enhanced dictionary class that interprets lists and sets of keys as requests for subdictionaries.

from yv import Subdict

d = {'a': 1, 'b': 2, 'c': 3}
dd = Subdict(d)
subdict = dd('a', 'b', c=100, d=100)  # Returns {'a': 1, 'b': 2, 'c': 3, 'd': 100}

MongoDB-style Querying

Filter dictionary items using a MongoDB-like query.

from yv import dict_filt_from_mg_filt

mg_filt = {'a': {'$gte': 10, '$lt': 20}}
filt = dict_filt_from_mg_filt(mg_filt)
result = list(filter(filt, [{'a': x} for x in range(9, 22)]))  # Returns [{'a': 10}, {'a': 15}]

Nested Key Paths

Set and get values in a dictionary using dot-separated string paths or lists of keys.

from yv import set_value_in_nested_key_path, get_value_in_key_path

d = {}
set_value_in_nested_key_path(d, 'a.b.c', 100)
print(d)  # Outputs: {'a': {'b': {'c': 100}}}

value = get_value_in_key_path(d, 'a.b.c')  # Returns 100

Utility Functions

Various utility functions to manipulate and query dictionaries.

from yv import left_union, all_but

d = {'a': 1, 'b': 2}
defaults = {'b': 3, 'c': 4}
new_d = left_union(d, defaults)  # Returns {'b': 2, 'c': 4, 'a': 1}

filtered_d = all_but(d, ['a'])  # Returns {'b': 2}

Documentation

Each function and class within the yv package is documented with docstrings, providing detailed usage instructions and examples. This documentation can be accessed via Python's built-in help system or by reading the source code directly.

For more detailed examples and usage, refer to the function and class definitions in the source code.