title: TableviewDataSource in own file does not conform to protocol UITableViewDataSource in swift
body: <p>Error:   <code>Type "MapListDataSource" does not conform to protocol "UITableViewDataSource"</code></p>
  
  <pre><code>import Foundation
  import UIKit
  import CoreData
  
  class MapListDataSource: NSObject, UITableViewDataSource    {
      func numberOfSectionsInTableView(tableView: UITableView) -&gt; Int {
         return 1
      }
      func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -&gt; UITableViewCell {
          let cell:UITableViewCell=UITableViewCell(style: UITableViewCellStyle.Subtitle, reuseIdentifier: "cell")
          return cell
      }
  }
  </code></pre>
  
  <p>I've tried implementing the minimal amount of functions you need to have UITableViewDatasource, still the compiler won't accept it. This is not implemented in the view controller, the data source is split out to its own file. Why is it not conforming to the protocol? Those two methods are the minimal requirement right?</p>