transfer (rotatory)

-- rotatory transfer
-- moves blocks from one direction to another by turning
-- expects a configuration with an opening (air) a left turn from first target
--   2
-- 1 t ?
--   _

local reverse_flow = false -- change the flow of blocks from 1 <- 2 to 1 -> 2
local reverse_side = false -- flip the spin direction so the air is to the right side

local first  = turtle.drop
local second = turtle.suck
local right  = turtle.turnRight
local left   = turtle.turnLeft
local temp

if reverse_flow then
  temp = first
  first = second
  second = temp
end

if reverse_side then
  temp = right
  right = left
  left = temp
end

-- reset direction
while turtle.detect() do right() end
while not turtle.detect() do right() end

-- start the transfer
while true do
  first()
  right()
  second()
  left()
  sleep(0)
end