gistfile1.rb

class Hello
  def self.attr_accessor_with_history(*names)
    names.each do |name|
      attr_reader name
      attr_reader "#{name}_with_history"

      define_method("#{name}=") do |v|
        if !instance_variable_defined?("@#{name}_with_history")
          instance_variable_set("@#{name}_with_history", [])
        end
        instance_variable_get("@#{name}_with_history") << instance_variable_set("@#{name}", v)
      end

    end
  end
end


# => nil