async-race.rb

##
# Demonstration of a race condition when using Async.

require "async"

Async {
  x = Async {
    5.times do
      @val = 2
      sleep rand(0.1)  # simulate random amounts of IO
      p({ 2 => @val }) # what is @val?
    end
  }

  y = Async {
    5.times do
      @val = 3
      sleep rand(0.1)  # simulate random amounts of IO
      p({ 3 => @val }) # what is @val?
    end
  }
  z = Async {
    5.times do
      @val = 4
      sleep rand(0.1)  # simulate random amounts of IO
      p({ 4 => @val }) # what is @val?
    end
  }
  x.wait
  y.wait
  z.wait
}