From: Norman Makoto Su <normsu@...>
Date: 2002-03-28T11:44:20+09:00
Subject: Threads in Iterators

This may be a dumb question with an obvious answer but, is it dangerous to have
threads in iterators?  For example:

arr = [1,2,3,4]
def arr.each
  0.upto(length-1) do |i|
    Thread.new(self[i]) {|val|
      sleep(rand .5) # or something else that may take a while
      yield val
    }
  end
end
vals = []
arr.each {|val|
  vals << val
}
Thread.list.each do |aThread|
  aThread.join if aThread != Thread.current
end
puts vals

My concern is if there is a chance that two yields will happen at the same time
and mess things up (vals will be corrupted).  Is this possible?

Thanks,

--
Norman Makoto Su