I’m new to swift.

This is a code from this sample becoming_a_now_playable_app, at AssetPlayer‘s handlePlayerItemChange() method.

guard let currentIndex = playerItems.firstIndex(where: { $0 == currentItem }) else { return } 

At here, playerItems is an array of AVPlayerItem, and currentItem is AVPlayerItem.

I can’t understand how this code works. How isEqual() possible for AVPlayerItem? I can’t find any overrided methods like isEqual() or hash() at AVPlayerItem.