Ruby.rb

module A
  def initialize
    puts 'A'
  end
end

module B
  def initialize
    puts 'B'
    super
  end
end

module C
  def initialize
    super
    puts 'C'
  end
end

class Stack
  include A
  include B
  include C
  def initialize
    super
    puts 'S'
  end
end

Stack.new