From: Robert Dober <robert.dober@...>
Date: 2008-06-16T19:14:55+09:00
Subject: Re: Fiber variables

On Sun, Jun 15, 2008 at 11:43 AM, Michael Fellinger
<m.fellinger@gmail.com> wrote:
> Hi list,
>
> I've been doing some playing with Fibers as a replacement of Thread
> for usage in Ramaze, and as I'm not the most knowledgable about this
> issue I'd like to request some code review from you guys.
>
> The code in question with some simple usage is at:
> http://p.ramaze.net/1618
>
> I'm not sure if i would run into any issues with this approach or why
> it hasn't been done in the fiber library already, but would you see
> this as a good use of fibers, to avoid having to pass state around for
> every component in the application/framework?
>
> My use case here is that you get a request from servers, possibly
> event driven, which just doesn't work well together with threading as
> it's done in ruby. So i take the request, create a couple of objects
> and put them into the fiber instance, to be accessed by Fiber.current.
> So it's kind of a reimplementation of what Thread.current[:a] = 1
> would do, but much more lightweight.
>
> Thanks in advance, please let me know when you have any more questions
> about this mail
> ^ manveru
>
>

I did not feel qualified to reply, but obviously nobody does :(. Well
it seems a simple and quite efficient solution to your problem. It
somehow is *obviously* right, I beware of the obvious but could not
find any gotchas.

Would it be possible that a different approach like an explicit hash
in Fiber would lead to cleaner code?

YourFiber = Class::new Fiber
   attr_reader :data
   def initialize *args, &blk
       super(*args, &blk)
       @data = {}
  end
end

I know the resulting code would be a little be less elegant as you
would have all the
Fiber.current.data[]
instead of Fiber.current[]

Going back to your original idea, why not using Forwardable?

class Fiber
  extend Forwardable
  def_delegators :@data, :[], :[]=
  alias_method :__old__init__, :initialize
  def initialize *args, &blk
    __old__init__ *args, &blk
    @data = {}
  end
end
class << Fiber
  extend Forwardable
  def_delegators :current, :[], :[]=
end


Just my 2cents

HTH
Robert











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---
As simple as possible, but not simpler.
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