From: "David A. Black" <dblack@...>
Date: 2009-12-22T20:08:43+09:00
Subject: Re: special cased?

Hi --

On Sun, 20 Dec 2009, Roger Pack wrote:

>
>> Class variables are a very strange beast with bizarre semantics. I would
>> avoid them if I were you.
>
> Yeah they must be special cased so that beginning users can use them
> with abandon and it will "just work."

See this, from Matz:

http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/347355

especially:

  (3) and lastly, and most importantly, do not use class variables,
      unless you really really need them; they are fundamentally global
      variables.

That's the thing; they're really hierarchy globals, but confusingly
similar to instance variables (of which they are essentially the
opposite) in appearance.


David

-- 
David A. Black
Senior Developer, Cyrus Innovation Inc.
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