From: "ara.t.howard" <ara.t.howard@...>
Date: 2007-10-23T02:12:50+09:00
Subject: Re: Conflicts between using respond_to? and extending Ruby


On Oct 22, 2007, at 10:39 AM, David A. Black wrote:

> The distinction I see is proximity to the object. respond_to? is
> asking the object about its capabilities, whereas kind_of? is asking
> it about its ancestry. So respond_to? is a tighter fit with the object
> as it is at a given point in runtime.

it all depends - consider the case of trying to tell wether or not a  
hash, array, or rbtree is passed to a method.  you can't use  
'respond_to?("[]")', 'respond_to?("size")', etc.  you can sometimes  
pick the 'right' method but, other times you cannot and

   case obj
     when Array
       ...

is safer and more accurate.  i think it really depends on the use  
case - i personally use both.

cheers.


a @ http://codeforpeople.com/
--
we can deny everything, except that we have the possibility of being  
better. simply reflect on that.
h.h. the 14th dalai lama