# Fiber variables

**URL:** <https://www.ruby-forum.com/t/fiber-variables/140509>\
**Category:** Ruby\
**Created:** [June 15, 2008, 11:47am UTC](https://www.ruby-forum.com/t/fiber-variables/140509 "2008-06-15T11:47:00Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![mifi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/7993a0/32.png) [@mifi](https://www.ruby-forum.com/u/mifi)\
**Post date:** [June 15, 2008, 11:47am UTC](https://www.ruby-forum.com/t/fiber-variables/140509/1 "2008-06-15T11:47:00Z")

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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](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

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<div class="post-metadata">

**Author:** ![mifi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/7993a0/32.png) [@mifi](https://www.ruby-forum.com/u/mifi)\
**Post date:** [June 16, 2008, 12:16pm UTC](https://www.ruby-forum.com/t/fiber-variables/140509/2 "2008-06-16T12:16:49Z")

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On Sun, Jun 15, 2008 at 11:43 AM, Michael F.  
[removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:

> it hasn’t been done in the fiber library already, but would you see  
> 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

–  
[http://ruby-smalltalk.blogspot.com/](http://ruby-smalltalk.blogspot.com/)

* * *

As simple as possible, but not simpler.  
Albert Einstein

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<div class="post-metadata">

**Author:** ![mifi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/7993a0/32.png) [@mifi](https://www.ruby-forum.com/u/mifi)\
**Post date:** [June 16, 2008, 2:42pm UTC](https://www.ruby-forum.com/t/fiber-variables/140509/3 "2008-06-16T14:42:59Z")

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On Mon, Jun 16, 2008 at 7:14 PM, Robert D. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)  
wrote:

> > would do, but much more lightweight.  
> > 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](http://p.ramaze.net/1627)

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<div class="post-metadata">

**Author:** ![mifi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/7993a0/32.png) [@mifi](https://www.ruby-forum.com/u/mifi)\
**Post date:** [June 16, 2008, 9:59pm UTC](https://www.ruby-forum.com/t/fiber-variables/140509/4 "2008-06-16T21:59:53Z")

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Michael F. 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](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?

I ended up wrapping evented mongrel calls with a Fiber and it seemed to  
work like a charm for my limited requests. Couple this with an evented  
DB and I think it has a lot of potential 🙂  
[This is what I was trying to do with ramaze on the group the other day,  
but had to give up since it wasn’t user friendly to beginners].

[http://rubyforge.org/pipermail/eventmachine-talk/2008-June/001881.html](http://rubyforge.org/pipermail/eventmachine-talk/2008-June/001881.html)  
lists a few code snippets.