title: convert obj-c block to swift 2 closure
body: <p>I have the following code - </p>
  
  <pre><code>[self.camera capture:^(LLSimpleCamera *camera, UIImage *image, NSDictionary *metadata, NSError *error) {
      if(!error) {    
         }
  }];
  </code></pre>
  
  <p>which, to me, should translate to </p>
  
  <pre><code>self.camera.capture({(camera: LLSimpleCamera, image: UIImage, metadata: [NSObject : AnyObject], error: NSError) -&gt; Void in
      if !error {
      }
  })
  </code></pre>
  
  <p>but it's throwing all the errors about 'cannot convert value of type etc, between the front and the return Void in section. Can someone tell me, is this a place when you have to use unSafeMutablePointers? If so, how would i know that.</p>
  
  <p>Thanks!</p>