Book Image

Polished Ruby Programming

By : Jeremy Evans
Book Image

Polished Ruby Programming

By: Jeremy Evans

Overview of this book

Anyone striving to become an expert Ruby programmer needs to be able to write maintainable applications. Polished Ruby Programming will help you get better at designing scalable and robust Ruby programs, so that no matter how big the codebase grows, maintaining it will be a breeze. This book takes you on a journey through implementation approaches for many common programming situations, the trade-offs inherent in each approach, and why you may choose to use different approaches in different situations. You'll start by refreshing Ruby fundamentals, such as correctly using core classes, class and method design, variable usage, error handling, and code formatting. Then you'll move on to higher-level programming principles, such as library design, use of metaprogramming and domain-specific languages, and refactoring. Finally, you'll learn principles specific to web application development, such as how to choose a database and web framework, and how to use advanced security features. By the end of this Ruby programming book, you’ll be a well rounded web developer with a deep understanding of Ruby. While most code examples and principles discussed in the book apply to all Ruby versions, some examples and principles are specific to Ruby 3.0, the latest release at the time of publication.
Table of Contents (23 chapters)
Section 1: Fundamental Ruby Programming Principles
Section 2: Ruby Library Programming Principles
Section 3: Ruby Web Programming Principles

Understanding that there are no class methods, only instance methods

Ruby programmers often refer to methods you can call on classes as class methods, and methods that you can call on modules as module methods. However, Ruby does not have class methods or module methods as separate concepts – it only has instance methods. Every method that you would think of as a class or a module method is just an instance method of the class or module's singleton class. That doesn't mean that you should stop using the terms class method or module method – it just means you should understand that these methods are not special and are just like all other methods.

You will often see class methods defined on classes in one of four ways. The most common way is to use self in front of the method, as shown here:

class Foo

This makes it obvious that the method being defined is a singleton method, because...