# File lib/scrubyt/utils/xpathutils.rb, line 133
    def self.generate_relative_XPath_from_XPaths(parent_xpath, child_xpath)
      original_child_xpath_parts = child_xpath.split('/').reject{|s|s==""}
      pairs = to_general_XPath(child_xpath).split('/').reject{|s|s==""}.zip to_general_XPath(parent_xpath).split('/').reject{|s|s==""}
      i = 0
      pairs.each_with_index do |pair,index|
        i = index
        break if pair[0] != pair[1]
      end
      "/" + original_child_xpath_parts[i..-1].join('/')
    end