title: Dictionary now gives error 'not convertible to BooleanLiteralConvertible' since updating to Swift 1.2
body: <p>I'm was just getting my head around Swift - then came Swift 1.2 (breaking my working code)!</p>
  
  <p>I have a function based on the code sample from <a href="http://nshipster.com/image-resizing/" rel="nofollow">NSHipster - CGImageSourceCreateThumbnailAtIndex</a>.</p>
  
  <p>My previously working code is:</p>
  
  <pre><code>import ImageIO
  
  func processImage(jpgImagePath: String, thumbSize: CGSize) {
  
      if let path = NSBundle.mainBundle().pathForResource(jpgImagePath, ofType: "") {
          if let imageURL = NSURL(fileURLWithPath: path) {
              if let imageSource = CGImageSourceCreateWithURL(imageURL, nil) {
  
                  let maxSize = max(thumbSize.width, thumbSize.height) / 2.0
  
                  let options = [
                      kCGImageSourceThumbnailMaxPixelSize: maxSize,
                      kCGImageSourceCreateThumbnailFromImageIfAbsent: true
                  ]
  
                  let scaledImage = UIImage(CGImage: CGImageSourceCreateThumbnailAtIndex(imageSource, 0, options))
  
                  // do other stuff
              }
          }
      }
  }
  </code></pre>
  
  <p>Since Swift 1.2, the compiler provides two errors relating to the <code>options</code> dictionary:</p>
  
  <ol>
  <li><em>Type of expression is ambiguous without more context</em></li>
  <li><em>'_' is not convertible to 'BooleanLiteralConvertible'</em>  (in ref to 'true' value)</li>
  </ol>
  
  <p>I have tried a variety ways to specifically declare the types in the options dictionary (eg. <code>[String : Any]</code>, <code>[CFString : Any]</code>, <code>[Any : Any]</code> ).  While this may solve one error, they introduce other errors.</p>
  
  <p>Can anyone please illuminate me??
  More importantly, can anyone please explain what changed with Swift 1.2 and dictionaries that stopped this from working.</p>