Pure and impure functions So far, all the functions we’ve written are pure. That is, they accept some argument or arguments, and return a result, behaving like a black box with no interaction with ...

This detailed tutorial shows how to implement pure functions in JavaScript that are deterministic and referentially transparent, and create no side effects.

25.2 Pure Functions In the world of programming, especially in functional programming paradigms, the concept of pure functions is fundamental. Pure functions are a cornerstone of writing predictable, ...

Explore the increasingly popular paradigm of functional programming in JavaScript! You’ll learn how to wield and manipulate functions to develop more readable, maintainable and manageable codebases.

First class functions Beyond the pure function ideal, in actual coding practice functional programming hinges on first class functions.

‘Higher-order functions’ is a fancy term for functions that take other functions as arguments or that return functions. Very powerful!