Ruby Object Model

ruby-object-model.rb

MyModule = Module.new

MyModule.module_eval do
  @module_ivar = 4
  
  class << self
    def my_singleton_method
      @module_ivar
    end
  end
  
  def my_module_method
  end
end

MyClass = Class.new

MyClass.class_eval do
  include MyModule
  
  @class_ivar = 0

  def initialize(ivar)
    @ivar = ivar
  end
  
  class << self
    def my_singleton_method
      @class_ivar
    end
  end
    
  def my_instance_method
    @ivar
  end
end

object_1 = MyClass.new(1)
object_2 = MyClass.new(2)

object_2.instance_eval do
  @another_ivar = 3
  
  def my_singleton_method
    @another_ivar
  end
end