A reminder of how ruby's access scope works in inheritance

ruby_method_access.rb

######
## A reminder of how ruby's access scope works in inheritance
## public: can be called by ownself, any other class
## protected: can be called by ownself, sibling class
## private: can be called by ownself
######

class Animal                                                                                                                                                                                                                     
  attr_reader :breed                                                                                                                                                                                                             
                                                                                                                                                                                                                                 
  def initialize(breed)                                                                                                                                                                                                          
    @breed = breed                                                                                                                                                                                                               
  end                                                                                                                                                                                                                            
                                                                                                                                                                                                                                 
  def speak                                                                                                                                                                                                                      
    p "#{breed} public speak"                                                                                                                                                                                                    
  end                                                                                                                                                                                                                            
                                                                                                                                                                                                                                 
  protected                                                                                                                                                                                                                      
                                                                                                                                                                                                                                 
  def habit                                                                                                                                                                                                                      
    p "#{breed} protected habit"                                                                                                                                                                                                 
  end                                                                                                                                                                                                                            
                                                                                                                                                                                                                                 
  private                                                                                                                                                                                                                        
                                                                                                                                                                                                                                 
  def behave                                                                                                                                                                                                                     
    p "#{breed} private behave"                                                                                                                                                                                                  
  end                                                                                                                                                                                                                            
end                                                                                                                                                                                                                              
                                                                                                                                                                                                                                 
class Dog < Animal                                                                                                                                                                                                               
  def speak                                                                                                                                                                                                                      
    p "Woof!"                                                                                                                                                                                                                    
    habit                                                                                                                                                                                                                        
    behave                                                                                                                                                                                                                       
    cat = Cat.new("orange")                                                                                                                                                                                                      
    cat.habit                                                                                                                                                                                                                    
    #cat.behave                                                                                                                                                                                                                  
  end                                                                                                                                                                                                                            
end                                                                                                                                                                                                                              
                                                                                                                                                                                                                                 
class Cat < Animal                                                                                                                                                                                                               
  def speak                                                                                                                                                                                                                      
    p "Meow!"                                                                                                                                                                                                                    
    habit                                                                                                                                                                                                                        
    behave                                                                                                                                                                                                                       
    dog = Dog.new("husky")                                                                                                                                                                                                       
    dog.habit                                                                                                                                                                                                                    
    #dog.behave                                                                                                                                                                                                                  
  end                                                                                                                                                                                                                            
end                                                                                                                                                                                                                              
                                                                                                                                                                                                                                 
corgi = Dog.new("corgi")                                                                                                                                                                                                         
persian = Cat.new("persian")                                                                                                                                                                                                     
corgi.speak                                                                                                                                                                                                                      
persian.speak

#########
# [2] pry(main)> load 'test_oop.rb'
# "Woof!"
# "corgi protected habit"
# "corgi private behave"
# "orange protected habit"
# "Meow!"
# "persian protected habit"
# "persian private behave"
# "husky protected habit"
# => true
#
# If we try to call the .behave private method of sibling class:
#
# NoMethodError: private method `behave' called for #<Cat:0x0000000107baa6a0 @breed="orange">
# from test_oop.rb:32:in `speak'
#
# We also can't call the .habit protected method from outside of the class:
#                                                                                                                                                                                                     
corgi.habit
# NoMethodError: protected method `habit' called for #<Dog:0x0000000164a2e378 @breed="corgi">
# from test_oop.rb:51:in `<main>'