title: Wrong items order when using .reverse() in Swift
body: <p>I know there are some similar questions here on SO, however I still cannot solve my issue and get to the point.</p>
  <p>The problem is simple: I want to get items from Firebase database in reversed order. I use .reverse() to do so. It works for some meaning of the word, the items are really rearranged, but the second one, for some reason, always goes last.</p>
  <p>Could someone please explain me the proper way to do reversing in such case? I would prefer to make reversing without creating new array. Is it possible? Here is my sample code.</p>
  <p>Any help would be greatly appreciated, thank you!</p>
  <pre><code>        Database.database().reference().child(&quot;posts&quot;).observe(.childAdded) { (snapshot) in
              
              let postId = snapshot.key
              
              guard let dictionary = snapshot.value as? Dictionary&lt;String, AnyObject&gt; else { return }
              
              let post = Post(postid: postId, dictionary: dictionary)
              
              postsArray.append(post)
  
              
              postsArray.reverse()
  
              self.finishedFetching = true
              
              self.collectionView.reloadData()
              
              }
  </code></pre>