typed-linq-collections 0.9.2

Complete LINQ, language integrated query, implementation for Python with full type annotations, comprehensive documentation, and 100% test coverage.

Typed Linq Collections

Complete LINQ, language integrated query, implementation for Python with full type annotations, comprehensive documentation, and 100% test coverage. Query any built in Iterable or use one of the queryable collections that are drop in replacements for standard collections.

• Rich Query API: Almost the full Enumerable set of operators from .NET gives excellent support for filtering, mapping, grouping, and more in a fluent API
• Comprehensive type annotions: Gives you full autocomplete and static error analysis if using pyright with vscode or PyCharm. In vscode refactoring within the lambdas work like a charm
• Comprehensive test suite: More than 900 tests covering every single line and code branch
• Comprehensive docstrings: Every method and class is documented, giving excellent discoverability of functionality in any modern IDE/editor.
• Lazy Evaluation: Memory efficient query execution with deferred evaluation for every operation other than the to_* methods which create new collections
• Drop-in compatible collection types: Collection types that seamlessly replace and interoperate with standard Python collections. QList, QSet, QDict etc
• Numeric Specializations: Dedicated types for int, float, Decimal, and Fraction collections
• Extensible Design: QIterable is an abstract class/mixin that can be subclassed by any Iterable type to add full querying capabilities

Quick Start

from typed_linq_collections.collections.q_list import QList
from typed_linq_collections.q_iterable import query


fruits = ("apple", "apricot", "mango", "melon", "peach", "pineapple")
def test_querying_built_in_collections() -> None:
    fruits_by_first_character = (query(fruits)
                                 .group_by(lambda fruit: fruit[0])
                                 .where(lambda group: group.key in {"a", "p"})
                                 .to_list())

    assert fruits_by_first_character == [['apple', 'apricot'], ['peach', 'pineapple']]

def test_querying_with_queryable_collections() -> None:
    fruits_by_first_character = (QList(fruits)
                                 .group_by(lambda fruit: fruit[0])
                                 .where(lambda group: group.key in {"a", "p"})
                                 .to_list())

    assert fruits_by_first_character == [['apple', 'apricot'], ['peach', 'pineapple']]

def test_numeric_operations() -> None:
    total_lenght_of_fruits = (query(fruits)
                              .select(len)
                              .as_ints() # get's you a QIntIterable with numeric operations support. typed so that it is only available on a QIterable[int]
                              .sum())

    assert total_lenght_of_fruits == 36

Collection Types

Core Collections

Drop in replacements for the built in collections.

• QList[T] - Queryable list (mutable sequence)
• QSequence[T] - Queryable immutable sequence
• QSet[T] - Queryable set (mutable)
• QFrozenSet[T] - Queryable frozen set (immutable)
• QDict[K, V] - Queryable dictionary
• QDefaultDict[K, V] - Queryable default dictionary

Numeric Collections

Specialized collections with additional numeric operations:

• QIntIterable - For integer collections
• QFloatIterable - For float collections
• QDecimalIterable - For Decimal collections
• QFractionIterable - For Fraction collections

and so on with equivalents for QList, QSet, QDict, QFrozenSet, QDefaultDict.