An Introduction to Functional Programming

Functional Programming has experienced a resurgence in popularity recently. It is not a stretch to assert that many a programmer has, in the years since the start of the paradigm’s rejuvenation, inadvertently or otherwise, interacted with a technique straight out of its playbook. What is this playbook composed of? Functions—fundamentally those of the pure kind. Purity, as you will come to see, is a significant factor in separating any code from paradigm-compliant code that is easy to reason about, test, and inject into applications to make them more coherent.