class Redis::Distributed

def brpoplpush(source, destination, **options)

until one is available.
Pop a value from a list, push it to another list and return it; or block 
def brpoplpush(source, destination, **options)
  ensure_same_node(:brpoplpush, [source, destination]) do |node|
    node.brpoplpush(source, destination, **options)
  end
end