From: Robert <bob.news@...>
Date: 2003-05-01T02:35:23+09:00
Subject: Re: Self modifying systems question


"Sten Kvamme" <skvamme@as4-2-8.an.g.bonet.se> schrieb im Newsbeitrag
news:3DF19A9C-7B0D-11D7-93CD-003065DC4D52@as4-2-8.an.g.bonet.se...
> Hello,
>
> Self modifying code is a well known technology. Has anyone done this in
> Ruby? What I'm seeking for is examples of software that adds to
> itself (methods and variables) in runtime.
>
> I understand from reading the Ruby documentation that it is easy
> to add a method programmatically to a running object instance, but
> is it also possible to maintain changes (persistance) after system
> halts?

I think not directly.  I guess you couls store a map from method name to
method code and recreate the methods after loading.

class Foo
  def initialize()
    @dynamic_methods = []
  end

  # some code that adds to @dynamic_methods

  def after_load()
    @dynamic_methods.each do |code|
      # code is something like "def foo(); puts 'foo'; end"
      instance_eval code
    end
  end
end

Regards

    robert