    # File lib/facets/more/pqueue.rb, line 186
      def push_all(elements)
        if empty?
          if elements.kind_of?(PQueue)
            initialize_copy(elements)
          else
            replace(elements)
          end
        else
          if elements.kind_of?(PQueue)
            @qarray[@size + 1, elements.size] = elements.qarray[1..-1]
            elements.size.times{ @size += 1; upheap(@size)}
          else
            ary = elements.to_a
            @qarray[@size + 1, ary.size] = ary
            ary.size.times{ @size += 1; upheap(@size)}
          end
        end
        return self
      end