Simple demo script for ruby libxml's reader api.

reader.rb

require "rubygems"
require "xml"

#parse the sample.xml ignoring whitespaces and
#performing entity substitution.
doc = XML::Reader.file("sample.xml", :options => XML::Parser::Options::NOBLANKS |
                                            XML::Parser::Options::NOENT
                      )

#display a node's name: local and prefix
def display_name( node )
    puts "\tName: #{node.name}"
    if node.prefix
        puts "\t\tPrefix: #{node.prefix}" if node.prefix
        puts "\t\tLocal: #{node.local_name}"
    end
end

#display attributes of a node
def display_attributes( node )
    node.attribute_count.times do | index |
        puts "Attribute # #{index + 1}"
        node.move_to_next_attribute
        display node
    end
    node.move_to_element
end

#process a node
def display( node )
    display_name node
    puts "\tDepth: #{node.depth}"
    puts "\tEmpty Element" if node.empty_element?
    puts "\tValue: #{node.value}" if node.has_value?
    display_attributes node
    print "\n"
end

#shift through the document.
i = 1
while doc.read
    unless doc.node_type == XML::Reader::TYPE_END_ELEMENT
        puts "Node # #{i}"
        display doc
        i += 1
    end
end

#free the resources
doc.close