Preface

Ever since the dawn of computers decades ago, there have been a number of programming languages created for the purpose of writing software. One of the earliest of these languages is Lisp, whose name is an abbreviation of the term "list processing". Lisp has evolved greatly over time, and there are now several dialects of Lisp. Each of these dialects emphasizes its own set of ideas and features. Clojure is one among these Lisps, and it focuses on immutability, concurrency, and parallelism. It emphasizes being simple, practical, and intuitive, which makes it easy to learn. It is said that you have never realized how a language can be powerful until you have programmed in a Lisp, and Clojure is no exception to this rule. A skilled Clojure programmer can easily and quickly create software that is both performant and scalable.

With the recent rise of parallel data processing and multicore architectures, functional programming languages have become more popular for creating software that is both provable and performant. Clojure brings functional programming to the Java Virtual Machine (JVM), and also to web browsers through ClojureScript. Like other functional programming languages, Clojure focuses on the use of functions and immutable data structures for writing programs. Clojure also adds a hint of Lisp through the use of symbolic expressions and a dynamic type system.

This book will walk you through the interesting features of the Clojure language. We will also discuss some of the more advanced and lesser known programming constructs in Clojure. Several libraries from the Clojure ecosystem that we can put to practical use in our own programs will also be described. You won't need to be convinced any more about the elegance and power of the Clojure language by the time you've finished this book.

This book wouldn't have materialized without the feedback from the technical reviewers and the effort of the content and editing teams at Packt Publishing.