Book Image

Agile Technical Practices Distilled

By : Pedro M. Santos, Marco Consolaro, Alessandro Di Gioia
Book Image

Agile Technical Practices Distilled

By: Pedro M. Santos, Marco Consolaro, Alessandro Di Gioia

Overview of this book

The number of popular technical practices has grown exponentially in the last few years. Learning the common fundamental software development practices can help you become a better programmer. This book uses the term Agile as a wide umbrella and covers Agile principles and practices, as well as most methodologies associated with it. You’ll begin by discovering how driver-navigator, chess clock, and other techniques used in the pair programming approach introduce discipline while writing code. You’ll then learn to safely change the design of your code using refactoring. While learning these techniques, you’ll also explore various best practices to write efficient tests. The concluding chapters of the book delve deep into the SOLID principles - the five design principles that you can use to make your software more understandable, flexible and maintainable. By the end of the book, you will have discovered new ideas for improving your software design skills, the relationship within your team, and the way your business works.
Table of Contents (31 chapters)
Free Chapter
Section 1
Section 2
Section 3
Section 4
Chapter 21
License: CyberDojo

Refactoring and the Rule of Three – Baby Steps

Refactoring is missing from the previous rules. We feel that TDD without refactoring is just half of the game. For the time being, in the refactoring phase, just look for duplication. But wait until you are sure you have a duplication pattern. Avoid removing duplication too soon, as this may lead you to extract the wrong abstractions.


Extract duplication only when you see it for the third time.

The Rule of Three defers duplication minimization until there is enough evidence of duplication. Code that does not contain duplication is often referred to as abiding by the Do not Repeat Yourself (DRY) principle.


Duplication is far easier to refactor than the wrong abstraction. Use the Rule of Three if you are not sure what the correct abstraction would look like.