Book Image

Functional Python Programming. - Second Edition

Book Image

Functional Python Programming. - Second Edition

Overview of this book

If you’re a Python developer who wants to discover how to take the power of functional programming (FP) and bring it into your own programs, then this book is essential for you, even if you know next to nothing about the paradigm. Starting with a general overview of functional concepts, you’ll explore common functional features such as first-class and higher-order functions, pure functions, and more. You’ll see how these are accomplished in Python 3.6 to give you the core foundations you’ll build upon. After that, you’ll discover common functional optimizations for Python to help your apps reach even higher speeds. You’ll learn FP concepts such as lazy evaluation using Python’s generator functions and expressions. Moving forward, you’ll learn to design and implement decorators to create composite functions. You'll also explore data preparation techniques and data exploration in depth, and see how the Python standard library fits the functional programming model. Finally, to top off your journey into the world of functional Python, you’ll at look at the PyMonad project and some larger examples to put everything into perspective.
Table of Contents (22 chapters)
Title Page
Packt Upsell
Contributors
Preface
Index

Chapter 2. Introducing Essential Functional Concepts

Most of the features of functional programming are already first-class parts of Python. Our goal in writing functional Python is to shift our focus away from imperative (procedural or object-oriented) techniques to as much of an extent as possible.

We'll look at each of the following functional programming topics:

  • First-class and higher-order functions, which are sometimes known as pure functions.
  • Immutable data.
  • Strict and non-strict evaluation. We can also call this eager versus lazy evaluation.
  • Recursion instead of an explicit loop state.
  • Functional type systems.

This should reiterate some concepts from the first chapter: firstly, that purely functional programming avoids the complexities of an explicit state maintained through variable assignments; secondly, that Python is not a purely functional language.

This book doesn't attempt to offer a rigorous definition of what functional programming is: Python is not a purely functional language...