title: How to use bool? in if statement?
body: <p>I want to use a nullable boolean in an if statement. But I get the following compiler error: <code>Cannot implicitly convert type 'bool?' to 'bool'. An explicit conversion exists (are you missing a cast?) csharp(CS0266)</code></p>
  <p>How can I easily cast <code>bool?</code> to <code>bool</code>?</p>
  <p>This is sample code that throws the error:</p>
  <pre class="lang-cs prettyprint-override"><code>bool? nullable = null;
  if(nullable) return;
  </code></pre>