From: Robert Klemme <shortcutter@...>
Date: 2007-05-10T21:05:08+09:00
Subject: Re: instance_variables doesn't return unassigned variables

On 10.05.2007 12:00, Bernd wrote:
> Hi,
> I wrote a code like this.
> 
> class ABC
>   attr_accesor :first, :second
> end
> 
> when I wrote the following:
> 
> x = ABC.new
> x.first = "test"
> puts x.instance_variables
> 
> the output was only
> 
> @first
> 
> Is there a possibility to get also the unassigned variables? I mean,
> they exist, but they are only nil.

Additionally to the other replies: you can also do something like this:

irb(main):001:0> Pair = Struct.new :first, :second
=> Pair
irb(main):002:0> Pair.new.members
=> ["first", "second"]

Kind regards

	robert