Introduction to Functional Programming

Functional programming might not be the first thing you think of when you think of Python, but the support is there, and it is quite extensive. Many Python developers do not seem to realize this: with a few exceptions, functional programming allows you to write more concise and efficient code.

When you write code using a functional style, your functions are designed to not have side effects: they take an input and produce an output without maintaining state or modifying anything not reflected in the return value. Functions that adhere to this ideal are referred to as purely functional.