Short quiz to test how well you know the ruby object model. See the [blog post](https://www.vector-logic.com/blog/posts/test-yourself-on-ruby-object-model) to have a go at the quiz

ruby_object_model_quiz.rb

# To test yourself on the actual quiz, see 
# https://www.vector-logic.com/blog/posts/test-yourself-on-ruby-object-model

puts "Question 1"
class First; end
f = First.new
puts f.class.superclass # Object
puts "\n\n"

puts "Question 2"
puts Class.ancestors # [ Class, Module, Object, Kernel, BasicObject ]
puts "\n\n"


puts "Question 3"
class Developer < Array; end
d = Developer.new
puts d.singleton_class.superclass # Developer
puts "\n\n"


puts "Question 4"
module A; end
module B; end
class Foo
  include A
  include B
end
puts Foo.new.class.ancestors[1] # Returns B
puts "\n\n"


puts "Question 5"
class Bar; end
puts Bar.ancestors.map(&:class) # [Class, Class, Module, Class]
puts "\n\n"


puts "Question 6"
puts BasicObject.instance_methods & [:object_id, :equal?, :inspect, :instance_of, :!=] # [ :equal?, :!= ]
puts "\n\n"


puts "Question 7"
class Baz; end
baz = Baz.new
puts baz.singleton_class.ancestors.size # Outputs 5
puts "\n\n"


puts "Question 8"
class Qux; end
Qux.class_eval{ def work; end }
puts Qux.instance_methods(false) # Outputs [:work]
puts "\n\n"


puts "Question 9"
module Italian
  def speak
    "#{super} 🤌"
  end
end

module Boxer
  def speak
    "Grrr, #{super}"
  end
end

class Rocky
  prepend Italian
  include Boxer
  def speak
    "Yo Adrian"
  end
end

puts Rocky.new.speak
puts Rocky.ancestors
puts "\n\n"


puts "Question 10"
class User
  def breathe; end
end
u = User.new
def u.dance; end

puts u.class.instance_methods(false).include?(:breathe) # true
puts u.class.instance_methods(false).include?(:dance) # false
puts u.singleton_class.instance_methods(false).include?(:dance) # true
puts u.singleton_class.instance_methods(false).include?(:breathe) # false