From: Joel VanderWerf <vjoel@...>
Date: 2008-07-15T02:25:42+09:00
Subject: Re: Ruby & Threads

Michael Boutros wrote:
> require 'enumerator'
> 
> holder = []
> 
> array = (1..10).to_a
> puts array.inspect
> 
> array.each_slice(3) do |group|
>   group.each do |number|
>     @thread = Thread.new do
>       puts "Starting #{number}...\n"
>       sleep(5)
>       holder << number
>     end
>   end
> end
> 
> @thread.join

#join is definitely a good idea, because otherwise (as you observed) the 
main thread will exit before the others have finished, but you are 
overwriting the @thread variable on each iteration through the loop.

The usual idiom for this is something like:

threads = array.map { Thread.new {...} }
threads.each {|th| th.join}

-- 
       vjoel : Joel VanderWerf : path berkeley edu : 510 665 3407