From: "David A. Black" <dblack@...>
Date: 2009-07-02T06:11:58+09:00
Subject: Re: attr_writers within blocks

Hi --

On Thu, 2 Jul 2009, Wijnand Wiersma wrote:

>
> Op 30 jun 2009, om 09:29 heeft Fabian Streitel het volgende geschreven:
>
>> I can only recommend this thread: http://www.ruby-forum.com/topic/190337
>> We had a nice discussion there on those kind of DSLish attr setters and
>> what would be the best way to implement them
>
> I actually like one of the proposed ways in that topic.
> Using a method that is both getter and setter.
> I decided to create a attr_accessor_special like this:
> def attr_accessor_special(*syms)
>   syms.each do | sym |
>     name=sym.to_s
>     send(:define_method, name) do | *args |
>       value = args[0]
>       self.instance_variable_set("@#{name}", value) if value
>       self.instance_variable_get("@#{name}")
>     end
>   end
> end
>
> No way to make a value nil again but I don't think that will be needed in my 
> case.

You could test to see whether args is empty (see my earlier post).


David

-- 
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