# File lib/xml/xpath.rb, line 3001
    def step(axis)
      iterator = get_iterator(axis)
      lstep = make_location_step
      lstep.set_iterator iterator
      oldnodes = @nodes
      @nodes = []
      oldnodes.each { |node|
        lstep.reuse node
        nodes = yield(lstep).nodes
        nodes.reverse! if iterator.reverse_order?
        merge nodes
      }
      self
    end