🧩 Module 05: Functional Programming

Functional Programming (FP) is a paradigm that treats computation as the evaluation of pure functions and avoids shared state and mutable data. This module focuses on building predictable, testable code using FP ideas in Python.

Estimated Time: 8-10 hours
Prerequisites: Module 01 (Foundations)
Level: ⭐⭐ Intermediate

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📚 Topics Covered

#	Topic	Description	Key Concepts
01	Pure Functions	Deterministic functions without side effects	determinism, referential transparency
02	Immutability	Avoid changing data in place	tuples, frozen data, copy-on-write
03	Higher-Order Functions	Functions that take/return functions	callbacks, composition
04	Lambda Expressions	Anonymous functions for short logic	lambda, inline functions
05	Map, Filter, Reduce	Transform and reduce collections	map, filter, reduce
06	Closures	Functions that remember outer variables	enclosing scope, nonlocal
07	Decorators	Functions that wrap other functions	@syntax, wrappers

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🎯 Learning Goals

By the end of this module, you should be able to:

• Write pure functions and reason about their behavior.
• Use immutable data to avoid accidental bugs.
• Compose logic with higher-order functions.
• Use lambda expressions for concise transformations.
• Leverage map/filter/reduce for collection processing.
• Build and use closures for stateful functions.
• Apply decorators to extend functionality cleanly.

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📂 Module Structure

05_functional_programming/
├── README.md
├── 01_pure_functions/
│   ├── README.md
│   ├── examples.py
│   ├── exercises.py
│   └── quiz.md
├── 02_immutability/
│   ├── README.md
│   ├── examples.py
│   ├── exercises.py
│   └── quiz.md
├── 03_higher_order_functions/
│   ├── README.md
│   ├── examples.py
│   ├── exercises.py
│   └── quiz.md
├── 04_lambda_expressions/
│   ├── README.md
│   ├── examples.py
│   ├── exercises.py
│   └── quiz.md
├── 05_map_filter_reduce/
│   ├── README.md
│   ├── examples.py
│   ├── exercises.py
│   └── quiz.md
├── 06_closures/
│   ├── README.md
│   ├── examples.py
│   ├── exercises.py
│   └── quiz.md
└── 07_decorators/
    ├── README.md
    ├── examples.py
    ├── exercises.py
    └── quiz.md

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Ready to start? Begin with 01_pure_functions!