1  use <util/flat.scad>
 2  
 3  module test_flat() {
 4      echo("==== test_flat ====");
 5      vt = [[[[1, 2], [3, 4]], [[5, 6], [7, 8]]]];
 6  
 7      assert(
 8          flat([1, 2, [3, 4]]) == [1, 2, 3, 4]
 9      );
10  
11      assert(
12          flat([[1, 2], [3, 4]]) == [1, 2, 3, 4]
13      );
14  
15      assert(
16          flat([[[[1, 2], [3, 4]], [[5, 6], [7, 8]]]]) == [[[1, 2], [3, 4]], [[5, 6], [7, 8]]]
17      );
18  
19      assert(
20          flat([[[[1, 2], [3, 4]], [[5, 6], [7, 8]]]], 2) == [[1, 2], [3, 4], [5, 6], [7, 8]]
21      );
22  
23      assert(
24          flat([[[[1, 2], [3, 4]], [[5, 6], [7, 8]]]], 3) == [1, 2, 3, 4, 5, 6, 7, 8]
25      );
26  }
27  
28  test_flat();