class Buffer
  new: (limit = 5) =>
    @limit = limit
    @data = {}

  add: (line) =>
    if #data == @limit
      table.remove @data, 0

    table.insert @data, line

with Buffer 10
  while true
    n = io.read!
    if n ~= nil
      \add n
    else
      break

  for _, i in pairs .data
    print i