Book Image

Functional Python Programming - Second Edition

By : Steven F. Lott
Book Image

Functional Python Programming - Second Edition

By: Steven F. Lott

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


In this chapter, we looked at ways in which we can apply functional design to the problem of serving content with REST-based web services. We looked at the ways that the WSGI standard leads to somewhat functional overall applications. We also looked at how we can embed a more functional design into a WSGI context by extracting elements from the request for use by our application functions.

For simple services, the problem often decomposes into three distinct operations: getting the data, searching or filtering, and then serializing the results. We tackled this with three functions: raw_data(), anscombe_filter(), and serialize(). We wrapped these functions in a simple WSGI-compatible application to divorce the web services from the real processing around extracting and filtering the data.

We also looked at the way that web services' functions can focus on the happy path and assume that all of the inputs are valid. If inputs are invalid, the ordinary Python exception handling will raise...