Why wont this conditional work in Swift 3?
<p>Hey prior to Swift 3 I previously used :</p>

<pre><code>if CustomUser.sharedInstance.numberOfCredits &gt; 0 {
}
</code></pre>

<p>Where <code>numberOfCredits</code> is <code>Double?</code>. Now I get the error: <strong><em>Binary operator '>' cannot be applied to operands of type 'Double?' and 'Int'</em></strong>. Why is this? So I change 0 to 0.0 and get <strong><em>Binary operator '>' cannot be applied to operands of type 'Double?' and 'Double'</em></strong>. Why doesn't this line work in Swift 3?</p>