title: How to check if my return value is used or was assigned at all to some variable?
body: <p>Why do I need this?</p>
  
  <p>For instance I have a method which returns an object (VKRequest) and looks like this:</p>
  
  <pre><code>VKRequest *request = [[VKUser currentUser] info];
  </code></pre>
  
  <p>A programmer can then initiate request as follows:</p>
  
  <pre><code>[request start];
  </code></pre>
  
  <p>If request should start immediately after method call, programmer should write following code:</p>
  
  <pre><code>[VKUser currentUser].startAllRequestsImmediately = YES;
  [[VKUser currentUser] info];
  </code></pre>
  
  <p>What I really want is to eliminate startAllRequestsImmediately property from VKUser class and perform requests immediately if returned value isn't used.</p>
  
  <p>Is it possible at all?</p>
  
  <p>Thx.</p>