"George Ogata" <g_ogata@[...].au>  schrieb im Newsbeitrag 
news:87zmvfx6u9.fsf@[...]..
>  Eric Mahurin <eric_mahurin@[...].com> writes:
> 
> > Anybody know how to generically copy (shallow like clone) an
> > object into another object?  It would be nice to handle the
> > case where the objects have a different class, but I would at
> > least like to know how to do it when the classes are the same.
> >
> > Here is an example of what I would like to do:
> >
> > dest = Object.new # or String.new if necessary
> > source = "hello world"
> > destid = dest.id
> >
> > source.clone_into(dest)
> >
> > dest             -> "hello world"
> > dest.id==destid  -> true
> > dest.class       -> String
> 
>  I hear that evil.rb has Object#become, which will do that with some
>  caveats.  Search "Object#become" in the list archives for more info.

If you just want to copy state you can do without evil magic (although not 
working for builtins like String, Array, Fixnum etc.):

class Object
  def set_from(o)
    o.instance_variables.each do |var|
      instance_variable_set( var, o.instance_variable_get( var ) )
    end
    self
  end
end

Kind regards

    robert