Book Image

Clean Code in JavaScript

By : James Padolsey
Book Image

Clean Code in JavaScript

By: James Padolsey

Overview of this book

Building robust apps starts with creating clean code. In this book, you’ll explore techniques for doing this by learning everything from the basics of JavaScript through to the practices of clean code. You’ll write functional, intuitive, and maintainable code while also understanding how your code affects the end user and the wider community. The book starts with popular clean-coding principles such as SOLID, and the Law of Demeter (LoD), along with highlighting the enemies of writing clean code such as cargo culting and over-management. You’ll then delve into JavaScript, understanding the more complex aspects of the language. Next, you’ll create meaningful abstractions using design patterns, such as the Class Pattern and the Revealing Module Pattern. You’ll explore real-world challenges such as DOM reconciliation, state management, dependency management, and security, both within browser and server environments. Later, you’ll cover tooling and testing methodologies and the importance of documenting code. Finally, the book will focus on advocacy and good communication for improving code cleanliness within teams or workplaces, along with covering a case study for clean coding. By the end of this book, you’ll be well-versed with JavaScript and have learned how to create clean abstractions, test them, and communicate about them via documentation.
Table of Contents (26 chapters)
1
Section 1: What is Clean Code Anyway?
7
Section 2: JavaScript and Its Bits
13
Section 3: Crafting Abstractions
16
Section 4: Testing and Tooling
20
Section 5: Collaboration and Making Changes

Bitwise operators

JavaScript has seven bitwise operators. The term bitwise here means to operate on binary numbers. These operators are rarely utilized but are useful to know about nonetheless:

  • Bitwise unsigned right-shift operator: >>>
  • Bitwise left-shift operator: <<
  • Bitwise right-shift operator: >>
  • Bitwise OR: |
  • Bitwise AND: &
  • Bitwise XOR: ^
  • Bitwise NOT: ~ (a unary operator)
Bitwise operations are incredibly rare in JavaScript since you're usually dealing with higher-level sequences of bits like strings or numbers. However, it's worth having at least a cursory understanding of bitwise operations so that if you encounter the need, you can cope.

All bitwise operators in JavaScript will first coerce their operands (or a singular operand, in the case of bitwise NOT ~) to a 32-bit integer representation. This means that, internally, a number such...