class Redis::Client

def call_pipelined(commands, options = {})
  options[:raise] = true unless options.has_key?(:raise)
  # The method #ensure_connected (called from #process) reconnects once on
  # I/O errors. To make an effort in making sure that commands are not
  # executed more than once, only allow reconnection before the first reply
  # has been read. When an error occurs after the first reply has been
  # read, retrying would re-execute the entire pipeline, thus re-issueing
  # already succesfully executed commands. To circumvent this, don't retry
  # after the first reply has been read succesfully.
  first = process(commands) { read }
  error = first if first.is_a?(RuntimeError)
  begin
    remaining = commands.size - 1
    if remaining > 0
      replies = Array.new(remaining) do
        reply = read
        error ||= reply if reply.is_a?(RuntimeError)
        reply
      end
      replies.unshift first
      replies
    else
      replies = [first]
    end
  rescue Exception
    disconnect
    raise
  end
  # Raise first error in pipeline when we should raise.
  raise error if error && options[:raise]
  replies
end