The Joy of Clojure

Chapter 7. Functional programming

 

This chapter covers

• Functions in all their forms
• Closures
• Thinking recursively
• Putting it all together: A* pathfinding

 

At the core of functional programming is a formal system of computation known as the lambda calculus (Pierce 2002). Clojure functions, in adherence with the lambda calculus, are first-class—they can be both passed as arguments and returned as results from other functions. This book isn’t about the lambda calculus. Instead we’ll explore Clojure’s particular flavor of functional programming. We’ll cover a vast array of useful topics, including function composition, partial evaluation, recursion, lexical closures, pure functions, function constraints, higher-order functions, and first-class ...