ComputerCraft Dig Program

local tArgs = {...}

local length = tonumber(tArgs[1])

if #tArgs ~= 1 then
    length = 1
end

for i= 1, length do
    if not turtle.dig() then
        fuel = turtle.getFuelLevel()
        if fuel < 1 then
            while not turtle.refuel() do
                term.clear()
                term.setCursorPos(1,1)
                print("Fuel level is ".. fuel)
                print("Waiting for fuel...")
            end
        end
        turtle.forward()
    end
    if not turtle.forward() then
        turtle.dig()
    end

end