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Saving dynamic Ruby classes

I have a question of curiosity. If I have a ruby ​​class, then I dynamically add class methods, class variables, etc. to it. At runtime, do I care to save the changed class definition so that the next time I run the application I can use it again?

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Just sorting an object (as others have said) will not work. Let's look at an example. Consider this class:

class Extras
  attr_accessor :contents
  def test
    puts "This instance of Extras is OK. Contents is: " + @contents.to_s
  end

  def add_method( name )
    self.class.send :define_method, name.to_sym do
      puts "Called " + name.to_s
    end
  end
end

Now let's write a program that creates an instance, adds a method to it and saves it to disk:

require 'extras'

fresh = Extras.new
fresh.contents = 314
fresh.test # outputs "This instance of Extras is OK. Contents is: 314"
fresh.add_method( :foo )
fresh.foo # outputs "Called foo"

serial = Marshal.dump( fresh )
file = File.new "dumpedExample", 'w'
file.write serial

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require 'extras'

file = File.new 'dumpedExample', 'r'
serial = file.read

reheated = Marshal.load( serial )
reheated.test # outputs "This instance of Extras is OK. Contents is 314"
reheated.foo # throws a NoMethodError exception

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