test = do
  x <- bin (tip 1,tip 2)
  y <- bin (tip 'A',tip 'B')
  return (x, y)
test = do
  x <- bin (tip 1,tip 2)
  y <- bin (tip 'A',tip 'B')
  return (x, y)
test = do
  x <- bin (tip 1,tip 2)
  y <- bin (tip 'A',tip 'B')
  return (x, y)