Accessing NS Type class category in swift-3
<p>I've <code>NSData</code> category for <code>base64Encoding</code> written in Obj-C.</p>

<pre><code>@interface NSData (Base64)

+ (NSData*)dataFromBase64String:(NSString*)aString;
- (NSString*)base64EncodedString;

@end
</code></pre>

<p>Initially in Swift 2.2, I was using it as:</p>

<pre><code>let dbPassData = NSData(fromBase64String: password)
</code></pre>

<p>Now, in Swift 3, there is no any <code>NSData</code>, instead have <code>Data</code>.</p>

<p><strong>How to use these category methods in swift 3?</strong></p>

<hr>

<p>After converting project to Swift 3, it converted that line as:</p>

<pre><code>let dbPassData = Data(fromBase64String: password)
</code></pre>

<p>which yields an error:</p>

<blockquote>
  <p>Argument labels do not match any available overloads</p>
</blockquote>