#!/usr/bin/ruby # example script to show a bug in REXML's xpath parsing when parentheses are used in selection criteria, # at least on descendant::node() # # Author: wiebe@halfgaar.net require 'rexml/document' doc = " test

A link.

" xmldoc = REXML::Document.new(doc) puts "The Following xpath expressions works fine..." # Works fine without parentheses xmldoc.elements.each("descendant::node()[local-name()='link' or local-name()='a' and @rel='sub']") do |element| puts "writing element: " puts element.to_s puts "" end puts "The following xpath expression is going to fail..." # This gives "/usr/lib/ruby/1.9.1/rexml/xpath_parser.rb:437:in `expr': undefined method `inject' for true:TrueClass (NoMethodError)" xmldoc.elements.each("descendant::node()[(local-name()='link' or local-name()='a') and @rel='sub']") do |element| puts "writing element: " puts element.to_s puts "" end