From: Robert Klemme <shortcutter@...>
Date: 2008-03-25T20:57:48+09:00
Subject: Re: thread.rb

2008/3/25, Adam Bender <abender@gmail.com>:
> I want to modify the Queue class in thread.rb, so I first searched for

Why?

>  P.S. On a related note, I want to add a method to the Queue class that
>  is similar to pop, but will take a timeout value and return nil if it
>  no item is push'ed before timeout seconds have elapsed.    Can anyone
>  suggest something better than the following:
>
>  class Queue
>   def pop_with_timeout(timeout)
>     elapsed = 0.0
>     while (Thread.critical = true; @que.empty?)
>       @waiting.push Thread.current
>       Thread.critical = false
>       elapsed += sleep(timeout - elapsed)
>       puts elapsed
>       return nil if elapsed >= timeout
>     end
>     @que.shift
>   ensure
>     Thread.critical = false
>   end
>  end
>
>  That was the first thing I came up with, and I'm (again) surprised
>  that it works - why does sleep ever return less than 1?  What
>  interrupts it?

I opt against using Thread.critical because this is a global exclusive
lock on all threads and it is unlikely to continue to exist in the
light of JRuby and others. I'd rather use Mutex#try_lock or Monitor's
#wait with timeout parameter.

Kind regards

robert

-- 
use.inject do |as, often| as.you_can - without end