Method overriding in Ruby - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is method overriding in Ruby?

Method overriding in Ruby is when a subclass provides its own version of a method that is already defined in its superclass. This allows the subclass to change or extend the behavior of that method.

beginner

How does Ruby decide which method to call when a method is overridden?

Ruby calls the method defined in the subclass if it exists. If not, it looks up the inheritance chain to find the method in the superclass.

intermediate

Can you override a method and still call the original method from the superclass in Ruby? How?

Yes, you can use the keyword super inside the overriding method to call the original method from the superclass.

intermediate

What happens if you call super without parentheses and arguments in an overriding method?

Ruby automatically passes all the arguments received by the overriding method to the superclass method when you call <code>super</code> without parentheses.

beginner

Show a simple example of method overriding in Ruby.

class Animal
  def speak
    "Hello"
  end
end

class Dog < Animal
  def speak
    "Woof!"
  end
end

puts Dog.new.speak  # Output: Woof!

What keyword is used in Ruby to call the superclass method from an overriding method?

A base

B parent

C super

D override

The keyword super calls the method with the same name in the superclass.

If a subclass overrides a method but does not call super, what happens?

A The superclass method is called automatically.

B The superclass method is ignored.

C An error occurs.

D Both methods run in sequence.

If super is not called, only the subclass method runs; the superclass method is ignored.

What will this code output? class A def greet "Hi" end end class B < A def greet super + ", there!" end end puts B.new.greet

A Error

B "Hi"

C ", there!"

D "Hi, there!"

The subclass method calls super which returns "Hi", then adds ", there!".

Which of these is true about method overriding?

A It allows a subclass to change the behavior of a method from its superclass.

B It creates a new method unrelated to the superclass.

C It deletes the superclass method.

D It only works with private methods.

Method overriding lets subclasses provide their own version of a method defined in the superclass.

In Ruby, if you want to pass different arguments to the superclass method when overriding, what should you do?

A Call <code>super</code> with the new arguments explicitly.

B Call <code>super</code> without arguments.

C You cannot pass different arguments.

D Use <code>super!</code> keyword.

To pass different arguments, you call super with those arguments explicitly.

Explain method overriding in Ruby and how the super keyword works.

Think about how a child class can change a parent's method but still use the parent's version.

Write a simple Ruby example showing a superclass method, a subclass overriding it, and using super to call the original method.

Start with a class Animal and subclass Dog, override speak method.