title: KVO - How to check if an object is an observer?
body: <p>When observing a value on an object using <code>addObserver:forKeyPath:options:context:</code>, eventually you'll want to call <code>removeObserver:forKeyPath:</code> on that object to clean up later. Before doing that though, is it possible to check if an object actually is observing that property?</p>
  
  <p>I've tried to ensure in my code that an object is only having an observer removed when it needs to be, but there are some cases where it's possible that the observer may try to remove itself twice. I'm working to prevent this, but just in case, I've just been trying to figure out if there's a way to check first if my code actually is an observer of something.</p>