--- title: "Meaning & Key Takeaway of: When Ruby programmers say that some class…" description: "\"“When Ruby programmers say that some class “quacks like an Array,” they usually mean that it’s not necessarily an Array nor a descendant of Array, but ..." image: "https://sms4smile.com/quotes/i/de0/armando-fox-73504_programming_when-ruby-programmers-say-that-some-clas_1719369.jpg" --- # When Ruby programmers say that some class “quacks like an… ![“When Ruby programmers say that some class “quacks like an Array,” they usually mean that it’s not necessarily an Array nor a descendant of Array, but it responds to most of the same methods as Array and can therefore be used wherever an Array would be used.” quote by Armando Fox](https://sms4smile.com/quotes/i/de0/armando-fox-73504_programming_when-ruby-programmers-say-that-some-clas_1719369.jpg) [Download](https://sms4smile.com/quotes/i/de0/armando-fox-73504_programming_when-ruby-programmers-say-that-some-clas_1719369.jpg) [Open image](https://sms4smile.com/quotes/i/de0/armando-fox-73504_programming_when-ruby-programmers-say-that-some-clas_1719369.jpg) > ““When Ruby programmers say that some class “quacks like an Array,” they usually mean that it’s not necessarily an Array nor a descendant of Array, but it responds to most of the same methods as Array and can therefore be used wherever an Array would be used.”” [Armando Fox](https://sms4smile.com/quotes/author/armando-fox/) ## About This Quote This interpretation was drafted with AI assistance. It is one reading of the quote, not the author's own explanation. A class can be used like an Array if it implements the same methods, even without inheriting from Array. **In simple terms:** Non‑Array class can act like an Array by matching its interface. Key Takeaway Design objects to match required interfaces. Themes polymorphism interface software design Mood technical analytical Type educational explanatory When to use this quote - API design - library usage - code reuse - testing - refactoring Key Concepts duck typing method compatibility Questions to Reflect On - What methods must your class implement to be interchangeable? - How does duck typing affect code safety? A Different Perspective If the class lacks subtle Array behaviors, substitution may fail. ★ ★ ★ ★ ★ No ratings yet [Array Responds](https://sms4smile.com/quotes/about/array-responds-1323712/) [Array Usually](https://sms4smile.com/quotes/about/array-usually-1323711/) [Like Array](https://sms4smile.com/quotes/about/like-array-1323715/) [Methods Array](https://sms4smile.com/quotes/about/methods-array-1323713/) [Necessarily Array](https://sms4smile.com/quotes/about/necessarily-array-1323714/) [Programming](https://sms4smile.com/quotes/about/programming/) [Technology](https://sms4smile.com/quotes/about/technology/) ## Related quotes > [Of everything I have done, 'The Archers' always gets the most excitement; there's a sort of uncontrollable joy from fans of the program.](https://sms4smile.com/quotes/felicity-jones/of-everything-i-have-done-the-archers-always-gets-the-most-excitement/) [Felicity Jones](https://sms4smile.com/quotes/author/felicity-jones/) > [I kind of pride myself on coming onto things that are well-oiled machines and finding a way to bring what I bring and fit…](https://sms4smile.com/quotes/rob-lowe/i-kind-of-pride-myself-on-coming-onto-things-that-are-well-oiled/) [Rob Lowe](https://sms4smile.com/quotes/author/rob-lowe/) > [I loved 'Chicago Code;' I watched that a lot. 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