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 delegation

Delegation refers to taking the arguments that were passed to one method and passing those arguments to a different method. In Ruby, it's common to use delegation to wrap calls to other methods in order to add behavior around the method call. Handling delegation incorrectly can make debugging and refactoring more difficult, so it useful to learn how best to implement it.

Let's say you have a public method you want to rename:

def foo(*args, **kwargs, &block)
  [args, kwargs, block]
end

Let's say you just rename the method, as follows:

def bar(*args, **kwargs, &block)
  [args, kwargs, block]
end

Here, you break backward compatibility for users calling foo.

The best way to handle this is to re-add the same method you are renaming, have it issue a deprecation warning, and then forward all arguments to the renamed method:

def foo(*args, **kwargs, &block)
  warn("foo is being renamed to...