--[[
Move functions
version 0.2
--]]

function shiftLeft(len)
  turtle.turnLeft()
  for i = 1,len do
    turtle.forward()dbs l
  end
  turtle.turnRight()
end

function shiftRight(len)
  turtle.turnRight()
  for i = 1,len do
    turtle.forward()
  end
  turtle.turnLeft()
end


-- main

local args = { ... }

if #args < 1 then
  return
end
local command = args[1]

local len = 1
if #args >= 2 then
  len = tonumber(args[2])
end

fnMove = nil
if command == "u" then
  fnMove = turtle.up
elseif command == "d" then
  fnMove = turtle.down
elseif command == "b" then
  fnMove = turtle.back
elseif command == "f" then
  fnMove = turtle.forward
elseif command == "r" then
  fnMove = turtle.turnRight
elseif command == "l" then
  fnMove = turtle.turnLeft
elseif command == "sl" then
  -- shift left
  shiftLeft(len)
  return
elseif command == "sr" then
  -- shift right
  shiftRight(len)
  return
end

if fnMove ~= nil then
  for i = 1,len do
    while not fnMove() do
    end
  end
end