title: Convert Expression<Func<T, bool?>> to Expression<Func<T, bool>>
body: <p>Simple question really.</p>
  
  <p>I have MVC view that displays a Nullable Bool, e,g,</p>
  
  <pre><code>Html.CheckBoxFor(model=&gt;model.NullableBoolHere, Model.NullableBoolHere, 
  </code></pre>
  
  <p>and I want to create a new html helper, that will accept this type, and then convert </p>
  
  <pre class="lang-none prettyprint-override"><code>Null || False =&gt; False
  True =&gt; True
  </code></pre>
  
  <p>so I have the following</p>
  
  <pre><code>public static MvcHtmlString CheckBoxFor&lt;TModel&gt;(this HtmlHelper&lt;TModel&gt; htmlHelper, Expression&lt;Func&lt;TModel, bool?&gt;&gt; expression, object htmlAttributes, bool disabled)
      {
          IDictionary&lt;string, object&gt; values = new RouteValueDictionary(htmlAttributes);
  
          if (disabled)
              values.Add("disabled", "true");
  
          Expression&lt;Func&lt;TModel, bool&gt;&gt; boolExpression = CONVERT_TO_BOOL_HERE(expression);
  
  
          return htmlHelper.CheckBoxFor(expression, values);
      }
  </code></pre>
  
  <p>Any help appreciated, I understand I will have to use recursion to copy the expression, but just not sure how to go about navigating the expression itself, find the bool?, convert to bool. </p>