ComputerCraft Tutorial: rotational boring_testcode

-- ##################################
-- rotational boring
-- this is test code.
-- http://hevohevo.hatenablog.com/

-- main
local MIN_FUEL_LEVEL = 300
local FUEL_SLOT = 16
i=0
function myRefuel()
  print("Fuel slot is ",FUEL_SLOT)
  turtle.select(FUEL_SLOT)
  while true do
    turtle.refuel()
    print("Current fuel level is ", turtle.getFuelLevel())
    if turtle.getFuelLevel() > MIN_FUEL_LEVEL then break end
    os.pullEvent("turtle_inventory")
  end
end

function digAndDown()
  for i=1,4 do
    turtle.dig()
    turtle.turnRight()
  end
  turtle.digDown()
  return turtle.down()
end

function recursive_trip()
  if digAndDown() then
    recursive_trip()
    turtle.up()
  end
  return
end

function trip()
  local depth = 0
  while digAndDown() do
    depth = depth + 1
  end
  for i=1, dpeth do
    turtle.up()
  end
end

myRefuel()
turtle.select(1)
trip()
--recursive_trip()