Multiple Inheritance in Ruby?

Question

I thought that Ruby only allowed single inheritance besides mixin. However, when I have class Square that inherits class Thing, Thing in t

Answer 1

If class B inherits from class A, then instances of B have the behaviors of both class A and class B

class A
end

class B < A
  attr_accessor :editor
end

Ruby has single inheritance, i.e. each class has one and only one parent class. Ruby can simulate multiple inheritance using Modules(MIXINs)

module A
  def a1
  end

  def a2
  end
end

module B
  def b1
  end

  def b2
  end
end

class Sample
  include A
  include B

  def s1
  end
end


samp=Sample.new
samp.a1
samp.a2
samp.b1
samp.b2
samp.s1

Module A consists of the methods a1 and a2. Module B consists of the methods b1 and b2. The class Sample includes both modules A and B. The class Sample can access all four methods, namely, a1, a2, b1, and b2. Therefore, you can see that the class Sample inherits from both the modules. Thus you can say the class Sample shows multiple inheritance or a mixin.