# File lib/backports/1.8.7/array.rb, line 63
    def recursively_flatten_finite(array, out, level)
      ret = nil
      if level <= 0
        out.concat(array)
      else
        array.each do |o|
          if ary = Backports.is_array?(o)
            recursively_flatten_finite(ary, out, level - 1)
            ret = self
          else
            out << o
          end
        end
      end
      ret
    end