From: "David A. Black" <dblack@...>
Date: 2007-09-22T18:41:49+09:00
Subject: Re: question re: modules and class variable scope

Hi --

On Sat, 22 Sep 2007, Gary Wright wrote:

> So despite the fact that class variables and instance variables both
> use a similar syntactical sigil (@@ vs @), they are scoped in vastly
> different ways.

I honestly wish that class variables looked like $$this, rather than
@@this. They're so completely unrelated to, and radically different
from, instance variables, whereas they're much more akin to globals.
The @/@@ thing has caused more confusion than anything else in Ruby, I
believe.

> class variables:  resolved at parse time relative to lexical scope
> instance variables: resolved at execution time relative to 'self'
>
> My advice is to just stay away from class variables entirely.  Simply use
> class instance variables instead.

I agree. If you want to maintain state per class, do it the way state
is normally maintained per object.


David

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