Book Image

Learn React with TypeScript 3

By : Carl Rippon
Book Image

Learn React with TypeScript 3

By: Carl Rippon

Overview of this book

React today is one of the most preferred choices for frontend development. Using React with TypeScript enhances development experience and offers a powerful combination to develop high performing web apps. In this book, you’ll learn how to create well structured and reusable react components that are easy to read and maintain by leveraging modern web development techniques. We will start with learning core TypeScript programming concepts before moving on to building reusable React components. You'll learn how to ensure all your components are type-safe by leveraging TypeScript's capabilities, including the latest on Project references, Tuples in rest parameters, and much more. You'll then be introduced to core features of React such as React Router, managing state with Redux and applying logic in lifecycle methods. Further on, you'll discover the latest features of React such as hooks and suspense which will enable you to create powerful function-based components. You'll get to grips with GraphQL web API using Apollo client to make your app more interactive. Finally, you'll learn how to write robust unit tests for React components using Jest. By the end of the book, you'll be well versed with all you need to develop fully featured web apps with React and TypeScript.
Table of Contents (14 chapters)

Generics

Generics can be applied to a function or a whole class. It's a mechanism for allowing the consumers, own type to be used with the generic function or class. The following sections go through examples of both of these.

Generic functions

Let's go through an example of a generic function. We are going to create a wrapper function around the fetch JavaScript function for getting data from a web service:

  1. Let's start by creating the function signature:
function getData<T>(url: string): Promise<T> {

}

We place a T in angled brackets after the function name to denote that it is a generic function. We can actually use any letter, but T is commonly used. We then use T in the signature where the...