Chapter 6. Acquiring Behavior Through Inheritance

Well-designed applications are constructed of reusable code. Small, trustworthy self-contained objects with minimal context, clear interfaces, and injected dependencies are inherently reusable. This book has, up to now, concentrated on creating objects with exactly these qualities.

Most object-oriented languages, however, have another code sharing technique, one built into the very syntax of the language: inheritance. This chapter offers a detailed example of how to write code that properly uses inheritance. Its goal is to teach you to build a technically sound inheritance hierarchy; its purpose is to prepare you to decide if you should.

Once you understand how to use classical inheritance, the ...

Get Practical Object-Oriented Design in Ruby: An Agile Primer now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.