Functional libraries for JavaScript

It's been said that every functional programmer writes their own library of functions, and functional JavaScript programmers are no exception. With today's open source code-sharing platforms such as GitHub, Bower, and NPM, it's easier to share, collaborate, and grow these libraries. Many libraries exist for functional programming with JavaScript, ranging from tiny toolkits to monolithic module libraries.

Each library promotes its own style of functional programming. From a rigid, math-based style to a relaxed, informal style, each library is different but they all share one common feature: they all have abstract JavaScript functional capabilities to increase code re-use, readability, and robustness.

At the time of writing, however, a single library has not established itself as the de-facto standard. Some might argue that underscore.js is the one but, as you'll see in the following section, it might be advisable to avoid underscore.js.