From: Jim Freeze <jim@...>
Date: 2001-05-18T04:01:57+09:00
Subject: [ruby-talk:15339] Re: How to clone an object?

On Fri, 18 May 2001, Dave Thomas wrote:
> 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]
>

Thanks, that works well. But, what if a is private.

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

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

  k1 = K.new
  k2 = k1.clone   #=> NameError: undefined method `a=' for #<K:0x815c25c>

Thanks


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Jim Freeze
jim@freeze.org
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