titanlock

I am trying to write a login program and have put it into the /boot directory but I get this error:

/lib/tools/boot.lua:71: /lib/term.lua:104: attempt to compare nil to number

Here is my Code:
 

local io = require("io")
local term = require("term")

term.clear()

while true do
	io.write("Password:")
	pass = io.read()
	if pass == "pass" then
  		print("Welcome!")
  		break
	else
  	print("Try again")
	end
end

I am new to lua so I have no idea what this error is telling me. Can someone please help.