Task

Write a function to flatten the nesting in an arbitrary list of values.

Your program should work on the equivalent of this list:

  [[1], 2, [[3, 4], 5], [[[]]], [[[6]]], 7, 8, []]

Where the correct result would be the list:

   [1, 2, 3, 4, 5, 6, 7, 8]

Related task

   Tree traversal


def (flatten seq acc)
  if no.seq
       acc
     ~list?.seq
       (cons seq acc)
     :else
       (flatten car.seq (flatten cdr.seq acc))