From: "ara.t.howard" <ara.t.howard@...>
Date: 2008-08-05T05:35:19+09:00
Subject: Re: Is it ellegant to use a global variable to store a Logger object?


On Aug 4, 2008, at 1:43 PM, Chuck Remes wrote:

> I hate to resurrect this thread, but I have a problem that I can't  
> seem to solve and I didn't want to rehash the original suggestions.
>
> I need a global Logger within a framework I wrote. The trouble is  
> that I need to be able to instantiate multiple independent copies of  
> this framework within the same Ruby runtime (specifically Jruby).
>
> If I do this it doesn't work for more than one instance:
>
> module Namespace
>  Logger = # instantiate some logger
>
>  module Submodule
>      class Klass
>        def foo
>          Logger.log("in Klass#foo")
>        end
>      end
>    end
> end
>
> I can load and instantiate this only once in the runtime. If I try  
> to do it a second time, it's like I have reopened the class/module  
> and Logger gets redefined. Each instantiation shares the same global  
> Logger which is *not* what I want. I want each one to have their own  
> instance.
>
> Is this possible? Any recommendations for solving it?
>
> cr
>
>

something similar to:



module Namespace
   module Logger
     def Logger.key *key
       @key = key.first unless key.empty?
     end

     def instance
       @instances = Hash.new{|h,k| @instances[key || :default ] ||= new}
     end

      %w( debug info warn error fatal ).each do |method|
       	module_eval <<-code
           def Logger.#{ method }(*a, &b)
             instance.#{ method }(*a, &b)
           end
         end
       end
    end
end


Namespace::Logger.key Thread.current.object_id   # or something unique

Namespace::Logger.info{ 'foobar' }

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