build_wall.lua

local l,w,h = ... -- 50, 40, 5
local function build_col(h)
    for ih=1,h do
        turtle.up()
        turtle.placeDown()
        if turtle.getItemCount()==0 then
            turtle.select(turtle.getSelectedSlot()+1)
        end
    end
    turtle.forward()
    while turtle.down() do end
end
local function build_wall(n,h)
    for i=1,n do
        build_col(h)
    end
end
--[[
build_wall(l-1)
turtle.turnLeft()
turtle.back()
build_wall(w-1)
turtle.turnLeft()
turtle.back()
build_wall(l-1)
turtle.turnLeft()
turtle.back()
build_wall(w)]]
return {build_wall=build_wall}