From: timr <timrandg@...>
Date: 2009-12-29T17:05:04+09:00
Subject: Re: PLEASE HELP...dup is not working correctly in the following code

On Dec 28, 10:49 pm, Rimantas Liubertas <riman...@gmail.com> wrote:
> > #dup creates a copy of an object with a different object_id. As
> > follows:
>
> <…>
>
>
>
>
>
> >> a = ["bar", "baz"]
> => ["bar", "baz"]
> >> b = a.dup
> => ["bar", "baz"]
> >> c = Marshal.load(Marshal.dump(a))
> => ["bar", "baz"]
> >> b[0] << "s"
> => "bars"
> >> b
> => ["bars", "baz"]
> >> a
> => ["bars", "baz"]
> >> c
> => ["bar", "baz"]
> >> a.object_id
> => 2157344160
> >> b.object_id
> => 2157338800
> >> c.object_id
> => 2157328340
> >> a[0].object_id
> => 2157344140
> >> b[0].object_id
> => 2157344140
> >> c[0].object_id
>
> => 2157328320
>
> Regards,
> Rimantas
> --http://rimantas.com

This is in effect the deep copy of a complex array containing strings
that we were pining for. I think it is easier to do it this ways than
to map through all of the nested arrays. Thanks for the irb demo of
its use.