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

Using JavaScript in ClojureScript

ClojureScript allows us to use JavaScript constructs. We can call JavaScript methods and functions like any other in ClojureScript. When we called Java from Clojure we used operators such as . dot or \ slash. Using JavaScript in ClojureScript will also require us to learn a new syntax.

While Java operates on classes a lot, in JavaScript we operate on objects. Two JavaScript constructs that we want to use on objects are:

  • Methods
  • Fields

In order to access a method from a JavaScript object, we place . (a dot) followed by a method name. Accessing a field of an object is very similar. We use .- (a dot and a hyphen) before the field name. You might wonder why accessing a function uses slightly different syntax than accessing a field. In JavaScript, an object can have a method and a field with the same name. In ClojureScript, we need a way to distinguish between a function call and a field access.

In JavaScript, the code looks as...