Book Image

Clojure Programming Cookbook

Book Image

Clojure Programming Cookbook

Overview of this book

When it comes to learning and using a new language you need an effective guide to be by your side when things get rough. For Clojure developers, these recipes have everything you need to take on everything this language offers. This book is divided into three high impact sections. The first section gives you an introduction to live programming and best practices. We show you how to interact with your connections by manipulating, transforming, and merging collections. You’ll learn how to work with macros, protocols, multi-methods, and transducers. We’ll also teach you how to work with languages such as Java, and Scala. The next section deals with intermediate-level content and enhances your Clojure skills, here we’ll teach you concurrency programming with Clojure for high performance. We will provide you with advanced best practices, tips on Clojure programming, and show you how to work with Clojure while developing applications. In the final section you will learn how to test, deploy and analyze websocket behavior when your app is deployed in the cloud. Finally, we will take you through DevOps. Developing with Clojure has never been easier with these recipes by your side!
Table of Contents (16 chapters)
Clojure Programming Cookbook
Credits
About the Authors
About the Reviewer
www.PacktPub.com
Preface

Using functional programming style


In this recipe, we will show you how to define and use anonymous functions and have functions as arguments and return functions. Using the concepts and techniques described here correctly provides higher abstraction.

Getting ready

This section does not make use of any external library, so you can just start a REPL and be ready.

How to do it...

First, let's see some functions take functional arguments.

Functions taking functions as their arguments

Clojure functions such as map and reduce can take functions as arguments.

map

The map function has already been seen in the previous chapters. The map function takes a function as the first argument, applies it to all elements of collection arguments, and returns a lazy sequence.

In the following example, map applies inc to all elements of the collection:

(map inc [1 2 3 4 5]) 
;;=> (2 3 4 5 6) 

The map function takes an arbitrary number of arguments and returns a lazy sequence. The following code applies +...