Book Image

TypeScript 4 Design Patterns and Best Practices

By : Theofanis Despoudis
Book Image

TypeScript 4 Design Patterns and Best Practices

By: Theofanis Despoudis

Overview of this book

Design patterns are critical armor for every developer to build maintainable apps. TypeScript 4 Design Patterns and Best Practices is a one-stop guide to help you learn design patterns and practices to develop scalable TypeScript applications. It will also serve as handy documentation for future maintainers. This book takes a hands-on approach to help you get up and running with the implementation of TypeScript design patterns and associated methodologies for writing testable code. You'll start by exploring the practical aspects of TypeScript 4 and its new features. The book will then take you through the traditional gang of four (GOF) design patterns in their classic and alternative form and show you how to use them in real-world development projects. Once you've got to grips with traditional design patterns, you'll advance to learning about their functional programming and reactive programming counterparts and how to couple them to deliver better and more idiomatic TypeScript code. By the end of this TypeScript book, you'll be able to efficiently recognize when and how to use the right design patterns in any practical use case and gain the confidence to work on scalable and maintainable TypeScript projects of any size.
Table of Contents (14 chapters)
1
Section 1: Getting Started with TypeScript 4
4
Section 2: Core Design Patterns and Concepts
8
Section 3: Advanced Concepts and Best Practices

Adapter pattern

The Adapter pattern deals with interfacing two different objects without changing their implementation part. You want to call new object methods using an existing interface but because they don't have something in common, you use a wrapper to connect them. Let's understand this concept in detail.

An Adapter is like a wrapper. It wraps one object in a new structure or interface that can be used in a client that expects that interface. This way, you can expand the usage of a particular object and make it work across incompatible interfaces.

We explain the fundamental reasons to use this pattern next.

When to use Adapter

In general terms, you want to use this pattern whenever you want to solve the following problems:

  • You have a client that expects an interface of type A but you have an object that implements type B: You don't want to implement interface A for the second object mainly because it is not suitable and because you cannot...