From: "Aleksi Niemelä" <aleksi.niemela@...>
Date: 2000-12-11T16:34:24+09:00
Subject: [ruby-talk:7035] RE:  XML-DOM Ruby implementation...

Clemens Wyss asked:

> is there (besides the SAX) a DOM implementaion available, which 
> allows adding/removing elements and writing the DOM-tree?

Well, XMLParser

  http://www.ruby-lang.org/en/raa-list.rhtml?name=XMLParser

does have a file xmltree.rb in it's lib directory. I strongly suspect you
can use it's classes in a DOM way (I've never really used DOM, so can't say
if this is fully compliant).

Here's an example, inserting a xpointer after each element:

	- Aleksi


  require 'xmltreebuilder'

  def annotateWithXPointer(node, recursively = false)
    if recursively
      node.childNodes do |child|
        if child.type == XML::Element
          annotateWithXPointer(child, recursively)
        end
      end
    end
    xpointer = node.makeXPointer(false)
    annotate = XML::Element.new("xpointer", nil, 
                                [XML::Text.new(xpointer)])
    node.insertBefore(annotate, node[0])
  end

  builder = XML::SimpleTreeBuilder.new
  xml = STDIN.read
  begin
    tree = builder.parse(xml)
  rescue XMLParserError => xpe
    line = builder.line
    print "#{$0}: #{xpe} in line #{line}\n"
    exit 1
  end

  root = tree.documentElement
  annotateWithXPointer(root, true)
  puts tree.to_s

Given this input

  <?xml version="1.0"?>

  <news>
  <title>
  Ruby Mine opens
  </title>
  <info>
      <submitter>Aleksi Niemela</submitter>
      <email>Aleksi.Niemela@ale.cx</email>
      <datetime>2000-11-11 02:45</datetime>
  </info>
  <body>
  <p>
  Just when the discussion sprouted on Ruby-talk
  I manage to finally open my site dedicated to Ruby and related biz and
  buzz.
  </p>

  <p>
  Even though there has been no public announcement yet, the site is
  fully accessible. Everything is still heavily under construction, so
  don't be surprised if something doesn't work. Let me know, while we
  probably are already working on it.
  </p>
  </body>
  </news>

it outputs

  <news><xpointer>root()</xpointer>
  <title><xpointer>root().child(1,title)</xpointer>
  Ruby Mine opens
  </title>
  <info><xpointer>root().child(1,info)</xpointer>
      <submitter><xpointer>root().child(1,info).child(1,submitter)
      </xpointer>Aleksi Niemela</submitter>
      <email><xpointer>root().child(1,info).child(1,email)</xpointer>
      Aleksi.Niemela@ale.cx</email>
    <datetime><xpointer>root().child(1,info).child(1,datetime)
     </xpointer>2000-11-11 02:45</datetime>
  </info>
  <body><xpointer>root().child(1,body)</xpointer>
  <p><xpointer>root().child(1,body).child(1,p)</xpointer>
  Just when the discussion sprouted on Ruby-talk
  I manage to finally open my site dedicated to Ruby and related biz and
  buzz.
  </p>

  <p><xpointer>root().child(1,body).child(2,p)</xpointer>
  Even though there has been no public announcement yet, the site is
  fully accessible. Everything is still heavily under construction, so
  don&apos;t be surprised if something doesn&apos;t work. Let me know,
  while we probably are already working on it.
  </p>
  </body>
  </news>