From: Peter Zotov <whitequark@...>
Date: 2011-05-18T21:14:17+09:00
Subject: Re: Making fibers enumerable

 On Wed, 18 May 2011 20:12:43 +0900, Robert Klemme wrote:
> How would your example look if there was another generation that you
> wanted to do concurrently?  Because for the single threaded generator
> case there is already a tool: Enumerator.new.  The example in the
> documentation even uses Fibonacci Numbers as example. :-)
>
> http://www.ruby-doc.org/core/classes/Enumerator.html#M000299
>
> fib_gen = Enumerator.new { |y|
>   a = b = 1
>   loop {
>     y << a
>     a, b = b, a + b
>   }
> }
>
> Now you can do exactly the same as you did with your example
>
> # Find the fibonacci number greater than 1000
> fib_gen.find {|x| x > 1000 }
> # take first 10 fibonacci numbers
> fib_gen.take 10
> # take_while numbers are smaller than 1000
> fib_gen.take_while {|x| x < 1000 }
>
> For this Fiber would be the wrong tool.

 The Enumerator.new uses Fibers internally. Check enumerator.c in the 
 sources;
 besides that, how would you achieve the needed effect without 
 coroutines?

-- 
   WBR, Peter Zotov.