prelude: |
  small_flat_ary = 5.times.to_a
  large_flat_ary = 100.times.to_a
  small_pairs_ary = [[1, 2]] * 5
  large_pairs_ary = [[1, 2]] * 100
  mostly_flat_ary = 100.times.to_a.push([101, 102])

benchmark:
  small_flat_ary.flatten: small_flat_ary.flatten
  small_flat_ary.flatten!: small_flat_ary.flatten!
  large_flat_ary.flatten: large_flat_ary.flatten
  large_flat_ary.flatten!: large_flat_ary.flatten!
  small_pairs_ary.flatten: small_pairs_ary.flatten
  small_pairs_ary.flatten!: small_pairs_ary.dup.flatten!
  large_pairs_ary.flatten: large_pairs_ary.flatten
  large_pairs_ary.flatten!: large_pairs_ary.dup.flatten!
  mostly_flat_ary.flatten: mostly_flat_ary.flatten
  mostly_flat_ary.flatten!: mostly_flat_ary.dup.flatten!
loop_count: 10000