Example Async equivalent to code naftilos76's code that phaul is helping with on #ruby IRC: https://gist.github.com/phaul/2b2166c913452f010b1513a8165ab287

async.rb

require 'async'

condition = Async::Condition.new

Async do
  task_one = Async do
    loop do
      puts 'task one before waiting'
      condition.wait
    end
  end

  Async do
    puts 'task two signalling'
    condition.signal
    puts 'still task two'
    task_one.stop
  end
end
#>> task one before waiting
#>> task two signalling
#>> task one before waiting
#>> still task two
#=> #<Async::Task:0xcefacedfe (complete)>