module EventMachine::Protocols::Redis

def call_command(argv, &blk)
  # async commands are 'a' prefixed
  if (argv.first[0] == 'a') && !SYNC.include?(argv.first.to_s)
    argv[0] = argv[0].to_s.slice(1,argv[0].size)
    old_call_command(argv, &blk)
  else
    # wrap response blocks into fiber callbacks
    # to emulate the sync api
    f = Fiber.current
    blk = proc { |v| v } if !block_given?
    clb = proc { |v| f.resume(blk.call(v)) }
    old_call_command(argv, &clb)
    Fiber.yield
  end
end