title: std::async - std::launch::async | std::launch::deferred
body: <p>I understand what <code>std::async</code> does with the following parameters.</p>
  
  <ul>
  <li><code>std::launch::async</code></li>
  <li><code>std::launch::deferred</code></li>
  </ul>
  
  <p>However what happens with, <code>std::launch::async | std::launch::deferred</code>?</p>