    # File lib/standard/facets/random.rb, line 156
        def pick!(n=nil)
          if n
            if n > self.size
              r = self.dup
              self.replace([])
              r
            else
              r = []
              n.times { r << delete_at(Random.number(size)) }
              r
            end
          else
            delete_at(Random.number(size))
          end
        end