TypeScript Crash Course

In this chapter, we will start working with TypeScript: the language Angular is written with. All the features that ECMAScript 2015 and ECMAScript 2016 provide, such as functions, classes, modules, and decorators, are already implemented in or added to the roadmap of TypeScript. Because of the extra type annotations, there are some syntactical additions compared to JavaScript.

Being already familiar with AngularJS and subsequently ES5, we'll go through a process of smooth transition to TypeScript. We'll start by introducing ES2015 and ES2016. As we mentioned previously, TypeScript is a superset of these new ECMAScript standards, which means that by learning the new versions of JavaScript you'll also learn very important bits of TypeScript. In the second half of the chapter, we'll add the extra syntax for explicit type annotations.

Later in this chapter, we will explain the extra features TypeScript provides, such as static typing and extra syntax. We will discuss the different consequences based on these features, which will help us to be more productive and less error-prone. Let's get going!