title: Swift 4 - expression was too complex to be solved in reasonable time swift
body: <p>I'm getting an error that this expression was too complex to be solved in reasonable time on swift 4
  Can anyone help me?</p>
  
  <pre><code>- AppDelegate.removeGIF(withURL: "images/" + self.currentUID + "/" + self.thisPostId + "." + self.currentGifExt)
  </code></pre>