title: Why is the HtmlHelper instance null in a Razor declarative @helper method?
body: <p>Using MVC 3 RTM I'm getting a strange <code>NullReferenceException</code>:</p>
  
  <pre><code>@helper TestHelperMethod() {
      var extra = "class=\"foo\"";
      &lt;div @Html.Raw(extra)&gt;&lt;/div&gt;
  }
  </code></pre>
  
  <p>It turns out that <code>Html</code> (of type <code>HtmlHelper</code>) is <code>null</code>.</p>
  
  <p>I've never seen this before in a regular view.  I'm starting to experiment with declarative helper methods in Razor (so far they seem a little limited) and I'm quite stumped by what I'm seeing here.</p>