anchor.diff:          pre(data-control='input-jade')
             code
               :jadesrc
  -              h1#title Welcolme to Jade
  +              h1#title Welcome to Jade
                 button.btn(data-action="bea") Awesome
         .col
           pre(data-control='output-html')
             code
               :htmlsrc
  -              <h1 id="title">Welcolme to Jade</h1>
  +              <h1 id="title">Welcome to Jade</h1>
                 <button class="btn" data-action="bea">
                   Awesome
                 </button>
  
positive.code: 
      p
        | The jade source for this file can be viewed (and edited/improved) on 
        a(href='https://github.com/visionmedia/jade/blob/gh-pages/src/pages/tutorial.jade') GitHub
negative.code:         pre
            code.output
              :htmlsrc
                <h1>Welcome to Jade</h1>
                <p>Text can be included in a number of
                   different ways.</p>
                <p>This way is shortest if you need big
  