Book Image

Essential Angular

By : Victor Savkin, Jeff Cross
Book Image

Essential Angular

By: Victor Savkin, Jeff Cross

Overview of this book

Essential Angular is a concise, complete overview of the key aspects of Angular, written by two Angular core contributors. The book covers the framework's mental model, its API, and the design principles behind it. This book is fully up to date with the latest release of Angular. Essential Angular gives you a strong foundation in the core Angular technology. It will help you put all the concepts into the right places so you will have a good understanding of why the framework is the way it is. Read this book after you have toyed around with the framework, but before you embark on writing your first serious Angular application. This book covers concepts such as the differences between Just-In-Time (JIT) and Ahead-Of-Time (AOT) compilation in Angular, alongside NgModules, components and directives. It also goes into detail on Dependency Injection and Change Detection: essential skills for Angular developers to master. The book finishes with a look at testing, and how to integrate different testing methodologies in your Angular code.
Table of Contents (11 chapters)

How is it possible?

Why did not we do it before, in Angular 1? To make AOT work the application has to have a clear separation of the static and dynamic data in the application. And the compiler has to built in such a way that it only depends on the static data. When designing and building Angular we put a lot of effort to do exactly that. And such primitives as classes and decorators, which the new versions of JavaScript and TypeScript support, made it way easier.

To see how this separation works in practice, let's look at the following example. Here, the information in the decorator is known statically. Angular knows the selector and the template of the talk component. It also knows that the component has an input called talk and an output called rate. But the framework does not know what the constructor or the onRate function do.

selector: 'talk-cmp',
template: `