From: Ehsanul Hoque <ehsanul_g3@...>
Date: 2009-09-19T09:19:28+09:00
Subject: Re: How to derive from DateTime?

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> It looks to me that this is a case where you might be better served by us=
ing
> composition and delegation rather than inheritance: instead of an Event
> being a specialized DateTime=2C it would have a DateTime instance as an
> instance variable and delegate certain methods (e.g.=2C year=2C etc.) to =
that
> instance variable.
>=20

I agree with Christopher here. What you want is a proxy class. Here's a way=
 you might implement it:

class Event

  def self.new( *args )


    class << datetime =3D DateTime.new(*args)

      def sweet

        "what a sweet method"

      end

    end

    datetime


  end

end


You could also try this way:


class Event
    instance_methods.each { |m| undef_method m unless m =3D~ /(^__|^send$|^=
object_id$)/ }

def initialize(*args)


  @date_time =3D DateTime.new(*args)


end

        def method_missing(name=2C *args=2C &block)
          @date_time.send(name=2C *args=2C &block)
        end
end


I'm sure you can figure out what's happening here=2C and how to merge it wi=
th your own code.

- Ehsan
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