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#406 Eloquent Ruby

Book notes - Eloquent Ruby, by Russ Olsen. First published January 27, 2011. Second Edition currently in beta - due Q1 2026.

Notes

This was the book that finally helped me crack the core concepts of lambdas, meta-programming and DSLs.

The first edition is showing its age now - written in the ruby 1.9 era, but a new Second Edition is on the way, due later in 2026.

cover

Contents - First Edition

  • Part I. The Basics
    • Chapter 1. Write Code That Looks Like Ruby
    • Chapter 2. Choose the Right Control Structure
    • Chapter 3. Take Advantage of Ruby’s Smart Collections
    • Chapter 4. Take Advantage of Ruby’s Smart Strings
    • Chapter 5. Find the Right String with Regular Expressions
    • Chapter 6. Use Symbols to Stand for Something
    • Chapter 7. Treat Everything Like an Object—Because Everything Is
    • Chapter 8. Embrace Dynamic Typing
    • Chapter 9. Write Specs!
  • Part II. Classes, Modules, and Blocks
    • Chapter 10. Construct Your Classes from Short, Focused Methods
    • Chapter 11. Define Operators Respectfully
    • Chapter 12. Create Classes That Understand Equality
    • Chapter 13. Get the Behavior You Need with Singleton and Class Methods
    • Chapter 14. Use Class Instance Variables
    • Chapter 15. Use Modules as Name Spaces
    • Chapter 16. Use Modules as Mixins
    • Chapter 17. Use Blocks to Iterate
    • Chapter 18. Execute Around with a Block
    • Chapter 19. Save Blocks to Execute Later
  • Part III. Metaprogramming
    • Chapter 20. Use Hooks to Keep Your Program Informed
    • Chapter 21. Use method_missing for Flexible Error Handling
    • Chapter 22. Use method_missing for Delegation
    • Chapter 23. Use method_missing to Build Flexible APIs
    • Chapter 24. Update Existing Classes with Monkey Patching
    • Chapter 25. Create Self-Modifying Classes
    • Chapter 26. Create Classes That Modify Their Subclasses
  • Part IV. Pulling It All Together
    • Chapter 27. Invent Internal DSLs
    • Chapter 28. Build External DSLs for Flexible Syntax
    • Chapter 29. Package Your Programs as Gems
    • Chapter 30. Know Your Ruby Implementation
    • Chapter 31. Keep an Open Mind to Go with Those Open Classes

Source Code - Second Edition

Source code is available from the Pragmatic Programmers listing. Getting the sources:

wget https://media.pragprog.com/titles/eruby2/code/eruby2-code.zip
unzip eruby2-code.zip
rm eruby2-code.zip

Credits and References

About LCK#406
BooksRuby

This page is a web-friendly rendering of my project notes shared in the LittleCodingKata GitHub repository.

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