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)
1
Section 1: Fundamental Ruby Programming Principles
8
Section 2: Ruby Library Programming Principles
17
Section 3: Ruby Web Programming Principles

Handling complexity trade-offs during method design

When designing your library, you have a choice of how many methods you should have in your library. You also have a choice of how many classes should make up your library, which you learned about in the The single-responsibility principle section in Chapter 2, Designing Useful Custom Classes. To implement the exact same features, you can often implement them using fewer, more complex, and more flexible methods, or more methods that are less complex and less flexible.

As an example, let's say you are designing a data access library, and one of your requirements is that you need to return the following types of data, assuming that N and O are integers, and criteria will be provided as a block that returns true or false when passed the record:

  • The first record
  • The first N records, as an array
  • The first record matching given criteria
  • The first N records matching given criteria, as an array
  • The record at...