code: def every_xsl_doc
        every_page do |page|
          if (block_given? && page.xsl?)
            if (doc = page.doc)
              yield doc
            end
          end
        end
      end
docs: Pass every XML Stylesheet (XSL) that the agent parses to a given
   block.
  
   @yield [doc]
     The block will be passed every XSL Stylesheet (XSL) parsed.
  
   @yieldparam [Nokogiri::XML::Document] doc
     A parsed XML document.
  
   @see http://nokogiri.rubyforge.org/nokogiri/Nokogiri/XML/Document.html