wally

function moveForward()
    if not turtle.forward() then
                if turtle.detect() then
                        if not turtle.dig() then
                                print("dig returning false after detect")
                                return false
                        else
                                if turtle.forward() == true then
                                        return true
                                else
                                        return moveForward()
                                end
                        end
                else
                        while turtle.attack() do
                                print("Turtle is attacking")
                        end
                        if turtle.forward() == true then
                                return true
                        else
                                return moveForward()
                        end
                end
        else
                return true
    end
end

function moveDown()
    if not turtle.down() then
        if turtle.detectDown() then
            if not turtle.digDown() then
                print("dig down returning false after detect")
                return false
                        else
                                turtle.down()
                                return true
                        end
                else
                        attack = True
                        while turtle.attackDown() do
                                turtle.attackDown()
                        end
                        turtle.down()
            return true
        end
    else
                return true
        end
end

function moveUp()
        if not turtle.up() then
                if turtle.detectUp() then
                        if not turtle.digUp() then
                                print("dig up returning false after detect")
                                return false
                        else
                                turtle.up()
                                return true
                        end
        else
            attack = True
                        while turtle.attackUp() do
                                turtle.attackUp()
            end
            turtle.up()
            return true
        end
    else
        return true
    end
end


local x=0
local z=0

local tArgs = {...}
    if #tArgs ~= 1 then
        print("Requires height")
        return
    end

local a = tonumber(tArgs[1])

--Go forward until you detect a wall.
repeat
moveForward()
x=x+1
until turtle.detect()


print("Wall!")
--Lets replace whatever is here, with whatever is in slot 1.  Lazy version, max of 64.
repeat
    turtle.dig()
    turtle.place()
    moveUp()
    z=z+1
until a==z

--All done, time to go back, on Y, then X.

--Go back on Z
repeat
    moveDown()
    z=z-1
until z==0

--Go back on X
repeat
    turtle.back()
    x=x-1
until x==0

--pastebin get 2mcArL4D test