title: Why BlockingCollection doesn't implement IProducerConsumerCollection?
body: <p>I recently needed an <code>IProducerConsumerCollection&lt;T&gt;</code> implementation but I wanted it to block on <code>TryAdd</code> if a certain capacity has been reached and block on <code>TryTake</code> if it's empty. I was certain that <code>BlockingCollection</code> is actually an implementation of <code>IProducerConsumerCollection&lt;T&gt;</code> but realised that this isn't the case. Why is that? </p>
  
  <p>Which property of <code>BlockingCollection</code> doesn't make it fit to implement the <code>IProducerConsumerCollection</code> interface? </p>
  
  <p>I understand that <code>BlockingCollection</code> is a wrapper around <code>IProducerConsumerCollection</code> but irrespective I thought that itself should be implementing the same interface.</p>