From: Dave Thomas <Dave@...>
Date: 2001-05-18T03:51:13+09:00
Subject: [ruby-talk:15338] Re: How to clone an object?

Jim Freeze <jim@freeze.org> writes:

> Sorry for responding to my own post, but the
> text below may be a bit more clear.
> 
> I have run across the following interesting situtation:
> 
> class K
>   attr_accessor :a
>   def initialize
>     @a = [1,2]
>   end
> end

> The question is, how do I get a copy of
> k2 where k2.a is a copy of k1.a and not a reference?


You could do something like:

  class K
    attr_accessor :a
    def initialize
      @a = [1,2]
    end

    def clone
      copy = super
      copy.a = a.clone
      copy
    end
  end

  k1 = K.new
  k2 = k1.clone

  k1.a[0] = 99
  k1.a       #=> [99, 2]
  k2.a       #=> [1, 2]


Regards

Dave