title: Using UIBezierPath:byRoundingCorners: with Swift 2 and Swift 3
body: <p>I'm using this code to make 2 corners of a button rounded. </p>
  
  <pre><code>let buttonPath = UIBezierPath(roundedRect: button.bounds,
                                byRoundingCorners: .TopLeft | .BottomLeft, 
                                cornerRadii: CGSizeMake(1.0, 1.0))
  </code></pre>
  
  <p>It throws an error:</p>
  
  <blockquote>
    <p>binary operator '|' cannot be applied to two UIRectCorner operands.</p>
  </blockquote>
  
  <p>How do I use this method in Swift 2.0?</p>