Book Image

The Clojure Workshop

By : Joseph Fahey, Thomas Haratyk, Scott McCaughie, Yehonathan Sharvit, Konrad Szydlo
Book Image

The Clojure Workshop

By: Joseph Fahey, Thomas Haratyk, Scott McCaughie, Yehonathan Sharvit, Konrad Szydlo

Overview of this book

The Clojure Workshop is a step-by-step guide to Clojure and ClojureScript, designed to quickly get you up and running as a confident, knowledgeable developer. Because of the functional nature of the language, Clojure programming is quite different to what many developers will have experienced. As hosted languages, Clojure and ClojureScript can also be daunting for newcomers because of complexities in the tooling and the challenge of interacting with the host platforms. To help you overcome these barriers, this book adopts a practical approach. Every chapter is centered around building something. As you progress through the book, you will progressively develop the 'muscle memory' that will make you a productive Clojure programmer, and help you see the world through the concepts of functional programming. You will also gain familiarity with common idioms and patterns, as well as exposure to some of the most widely used libraries. Unlike many Clojure books, this Workshop will include significant coverage of both Clojure and ClojureScript. This makes it useful no matter your goal or preferred platform, and provides a fresh perspective on the hosted nature of the language. By the end of this book, you'll have the knowledge, skills and confidence to creatively tackle your own ambitious projects with Clojure and ClojureScript.
Table of Contents (17 chapters)
Free Chapter
2
2. Data Types and Immutability

Advanced Call Signatures

So far, we have been declaring functions with one arity (with only a fixed number of arguments), and simply binding the arguments passed to a function to some parameter names. However, Clojure has a few techniques to allow more flexibility when calling functions.

Destructuring Function Parameters

First, everything we have just learned about destructuring applies to function parameters. Yes, you read that correctly – we can use destructuring techniques right in the function parameter declaration! As promised, here's our first stab at refactoring the print-flight functions from the previous exercise. Observe, in the following example, how sequential destructuring is used directly in the function parameters:

user=>
(defn print-flight
  [[[lat1 lon1] [lat2 lon2]]]
    (println (str "Flying from: Lat " lat1 " Lon " lon1 " Flying to: Lat " lat2 " Lon " lon2)))
#'user...