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


 
flatten: function [
    "Flatten the block"
    block [any-block!]
][
    load form block
]
 
red>> flatten [[1] 2 [[3 4] 5] [[[]]] [[[6]]] 7 8 []]
== [1 2 3 4 5 6 7 8]
 
;flatten a list to a string
>> blk: [1 2 ["test"] "a" [["bb"]] 3 4 [[[99]]]]
>> form blk
== "1 2 test a bb 3 4 99"