title: Why there is no std::future::try_wait()?
body: <p>Given that there are <code>std::future::wait_for/until()</code>, I don't see why there is no <code>std::future::try_wait()</code>. I'm currently writing a producer-consumer example, and I want to use <code>std::future</code> as a convenient way to signal the consumer threads to return. My consumer code is like</p>
  
  <pre><code>void consume(std::future&lt;void&gt;&amp; stop) {
    while (!stop.try_wait()) { // alas, no such method
      // try consuming an item in queue
    }
  }
  </code></pre>
  
  <p>I'm thinking to simulate <code>try_wait()</code> with a zero-duration <code>wait_for()</code> which is really ugly. As a side question: any other convenient ways to signal the consumer threads to return?</p>