bundle agent t
{
  vars:
    any::
      # Lists we get as inputs from ENC
      "ntp_servers"
          slist => {
                     "ntp1.conectiv.com",
                     "208.90.144.72 # ntp0.jrc.us",
                     "bonehed.lcs.mit.edu minpoll 9 # server seems to have a strong rate limiting",
                     "timekeeper.isi.edu"
          } ;

      # Data transformations, as suggested by Ted Zlatanov, to create an
      # index for this list (getindices on plan slist doesn't work, so
      # we build a list in a data container)
      "ntp_data"
          data => mergedata("ntp_servers") ;

      # This list will contain the indexes for all the entries that are
      # now in both ntp_servers and ntp_data. Using these indexes, it's
      # easier to transform the strings into something usable
      "idx" slist => getindices("ntp_data") ;

      # This will first create an array that maps the index, which is a
      # valid array key, to a list of two elements: the first element
      # is the NTP server, the second is whatever follows, if anything.
      "ntp_data_split[$(idx)]"
          slist => string_split(
                                 nth("ntp_data", "$(idx)"), # idx-th element of ntp_data
                                 "\s+", # split at 1 or more spaces
                                 2 # in two pieces at most
          ) ;

      # ...then we dig into ntp_data_split and pull out the first
      # element of each slist into the value, which means: we are
      # mapping each index with the corresponding NTP server
      "server_name[$(idx)]"
          string => nth("ntp_data_split[$(idx)]",0) ;

      # If everything went well thus far, the values of server_name
      # are all our NTP servers by now
      "server_names"
          slist => getvalues("server_name") ;


  reports:
      "DEBUG: server: $(server_names)" ;
}