From: Jim Freeze <jim@...>
Date: 2003-05-09T08:29:48+09:00
Subject: Re: Can a global be a constant?

On Friday,  9 May 2003 at  8:16:04 +0900, dblack@superlink.net wrote:
> Hi --
> 
> Would this be suitable?
> 
>   class App
>     class << self
>       attr_reader :state
>     end
>     State = Struct.new(:debug, :verbose)
>     @state = State.new(true, false)
>     def main
>       Work.new
>     end
>   end
> 
>   class Work
>     def initialize
>       puts App.state.debug
>     end
>   end
> 
>   App.new.main


Close.
Now, realize, I'm just now learning about this
weird class << self stuff. Is that just a fancy
way of doing:
  class App
    def self.state; @state; end
  end

So, I think the problem with this is that
Work does not know the name of App.
So, maybe I am dreaming here, but it would
be nice if I could do the following:

  class App
    def main
      State.new(true, true)
      Work.new #=> true, true
      State.new(false, false)
      Work.new #=> false, false
    end
  end

I realize that I have not shown the object
that gets tied to the first Work.new and
another object that gets tied to the second
work.new, but you get the idea. This may
not be possible, because, I am implying that I
also want any class that Work creates to use
the same state that Work has.

In leu of this option, I guess I am back to a
single global state, which may best be implemented
in the form of a mix-in.

-- 
Jim Freeze
----------
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