Book Image

Learning TypeScript 2.x - Second Edition

By : Remo H. Jansen
Book Image

Learning TypeScript 2.x - Second Edition

By: Remo H. Jansen

Overview of this book

TypeScript is an open source and cross-platform statically typed superset of JavaScript that compiles to plain JavaScript and runs in any browser or host. This book is a step-by-step guide that will take you through the use and benefits of TypeScript with the help of practical examples. You will start off by understanding the basics as well as the new features of TypeScript 2.x. Then, you will learn how to work with functions and asynchronous programming APIs. You will continue by learning how to resolve runtime issues and how to implement TypeScript applications using the Object-oriented programming (OOP) and functional programming (FP) paradigms. Later, you will automate your development workflow with the help of tools such as Webpack. Towards the end of this book, you will delve into some real-world scenarios by implementing some full-stack TypeScript applications with Node.js, React and Angular as well as how to optimize and test them. Finally, you will be introduced to the internal APIs of the TypeScript compiler, and you will learn how to create custom code analysis tools.
Table of Contents (17 chapters)

The example application

In this chapter, we are going to develop an entire web application. The application itself is not a very realistic example, but should be realistic enough to demonstrate many kinds of testing practices and technologies. We are going to develop a calculator that can perform the pow operation. The calculator application is composed of the following components:

  • A graphic user interface that is implemented using React, and fetches the result of the pow operation from a web service using an HTTP client
  • A web service that is implemented using Node.js and Express.js, and finds the result of the pow operation using a small math library

The application's graphic user interface looks as follows:

We are going to define many different automated tasks using npm scripts. Each task uses different tools, and some tasks must take place before others. We could use...