Ruler

-- Advanced Ruler by Henness
-- Version 1.0 1/2/2013

-- Functions
function measure(n)
    term.clear()
    term.setCursorPos(1,1)
    print("Measuring " .. distance .. " blocks...")
    for i=1,n do
        local moved = turtle.forward()
        if not moved and turtle.detect() then
            repeat turtle.dig() until turtle.forward()
            local moved = true
        elseif not moved and not turtle.detect() then
            repeat turtle.attack() until turtle.forward()
        end
    end
    print("Measured " .. n .. " distance.")
end

-- RUN
local tArgs = { ... }
if #tArgs == 1 and tonumber(tArgs[1]) > 0 then
    distance = tonumber(tArgs[1])
    if turtle.getFuelLevel() >= distance then
        measure(distance)
    else
        Print("Please Refuel Turtle.")
    end
else
    print("Usage: " .. shell.getRunningProgram() .. " <Distance>")
end