From: Michael Fellinger <m.fellinger@...>
Date: 2008-06-16T21:40:50+09:00
Subject: Re: Fiber variables

On Mon, Jun 16, 2008 at 7:14 PM, Robert Dober <robert.dober@gmail.com> wrote:
> 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?

I actually ended up with just subclassing Fiber:
http://p.ramaze.net/1627

> 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