Cannot convert return expression of type 'AnyObject' to return type 'NSComparisonResult'

Question

I have a Swift based iOS application. I am trying to use one of the Swift sort methods to sort my array of objects by the "createdAt" NSDate property.

My array has a bunch of PFObject - these objects have different properties including an NSDate property called "createdAt".

All I want to do, is to order the array so that the objects which are the oldest, are sent to the bottom of the array.

Here is my code:

let sortedArray = (self.statusData.copy() as! NSArray).sortedArrayUsingComparator { (obj1, obj2) -> NSComparisonResult in

  if (((obj1 as! PFObject).createdAt?.compare((obj2 as! PFObject).createdAt!)) == NSComparisonResult.OrderedDescending) {
      return obj2
  }

  else {
      return obj1
  }
}

However when I try to return the objects, I get the following error:

Cannot convert return expression of type 'AnyObject' to return type 'NSComparisonResult'

I don't understand whats wrong, why can't I just return the date comparison result which is determined my if statement?

Thanks for your time, Dan.

Answer 1

Your problem is that it's expecting a return type of NSComparasonResult and you're returning anAnyObject. However, you are already getting an NSComparasonResult in your existing code. Therefore, simply replace all of that with this:

let sortedArray = (self.statusData.copy() as! NSArray).sortedArrayUsingComparator { (obj1, obj2) -> NSComparisonResult in
    return (obj1 as! PFObject).createdAt?.compare((obj2 as! PFObject).createdAt!)
}