Receiving Lua Commands

rednet.open("back")
local x = 1
while true do
  sleep(1)
  local monitor = peripheral.wrap("top")
  local senderID, message, distance = rednet.receive()
  if message == "clear()" then
  monitor.clear()
  monitor.setCursorPos(1,1)
  x = 1
  elseif message == "nline()" then
  x = x + 1
  monitor.setCursorPos(1,x)
  else
    local index = string.find(message.." ","/n")
    if index == nil then
        shell.run(message)
    else
        x = x + 1
        monitor.setCursorPos(1,x)
        message = message:gsub("%/n", "")
        shell.run(message)
    end
 end
end