$def with (form, preview)

$if preview != None:
    $ link = preview
    <div class="preview">
      $if not link.URL:
          <b>$link.title</b>
      $else:
	  <a href="$link.URL">$:link.URL_description</a>
      $:link.description
      $if link.extended:
          <p>$:link.extended
    </div>
<p>

<div id="commentform">
<form name="main" method="post"> 
$:form.render_css()
<br/>
<input type="submit" name="post" value="Post"/>
<input type="submit" name="preview" value="Preview"/>
</form>
</div>