What this book covers

Chapter 1, Getting Started with Clojure, is your first step with Clojure, from how to install an interpreter, how to use the IntelliJ plugin Cursive Clojure, and how to start writing your first lines of code in Clojure.

Chapter 2, Namespaces, Packages, and Tests, deals with how every other language needs a way to organize our code. We do it with namespaces, and we start learning by doing little experiments and by comparing with the Java packages we already know.

Chapter 3, Interacting with Java, discusses the fact that one of the most useful features of Clojure is that it can be hosted on top of other platforms. Java is probably one of the most common platforms, and here we learn how to interact with Java code and libraries and how to expose our Clojure code to Java.

Chapter 4, Collections and Functional Programming, tells us that functional programming and immutable data structures (or collections) are fundamental to programming in the Clojure language; here we understand how we can write meaningful programs using immutable data structures and how functional programming is ideal for that.

Chapter 5, Multimethods and Protocols, introduces new tools and ideas of Clojure that help you write much more flexible and simple codes. Destructuring allows you to gain instant access to the data you need from a data structure. Multimethods and protocols are similar to Java's polymorphism but give you a whole new level of flexibility that you could only dream about.

Chapter 6, Concurrency, tells us about how in the modern world concurrency plays an extremely important part. This chapter also tells us about Clojure's native primitives for concurrency and again you will learn why immutable data structures are a great ally when writing concurrent programs.

Chapter 7, Macros in Clojure, deals with the fact that these are not the Excel macros you are used to, they are a way in which you can modify your program's source code at compile time. This is one of Lisp's big ideas and one that gives you immense flexibility. Here we understand a little of how to use this feature.