Introduction to TypeScript
As we learned in the previous chapter, where we built our very first Angular application, the code of an Angular project is written in TypeScript. Writing in TypeScript and leveraging its static typing gives us a remarkable advantage over other scripting languages. This chapter is not a thorough overview of the TypeScript language. Instead, we’ll focus on the core elements and study them in detail on our journey through Angular. The good news is that TypeScript is not all that complex, and we will manage to cover most of its relevant parts.
In this chapter, we’re going to cover the following main topics:
- The history of TypeScript
- Types
- Functions, lambdas, and execution flow
- Common TypeScript features
- Decorators
- Advanced types
- Modules
We will first investigate the background of TypeScript and the rationale behind its creation. We will also learn what tools and online resources are available to practice with TypeScript. We will emphasize the typing system, which is the main advantage of TypeScript, and learn how we can use it to create some basic types. We will expand our typing knowledge by learning how to use classes, interfaces, and advanced types in the Angular context. At the end of the chapter, we will explore how to organize the structure of an application by combining the typing system with modules.
