startup:2: attempt to index ? (a nil value)

I made a program to automate my mob farm I am using the MindCrack pack (latest update) and I keep getting the error startup:2: attempt to index ? (a nil value)
The code was:
while true do
turtle.attack()
os.sleep(1)
end
What am I doing wrong?
Edit: Nevermind, I was using an XP melee turtle I guess that made it not work

Split into new topic. Next time, please use the New Members Needing to Ask Questions topic.

Semanari, on 10 May 2013 - 10:31 PM said:

while true do
turtle.attack()
os.sleep(1)
end

should work fine in any turtle with a sword. you must've spelt turtle wrong in the actual game