title: Detecting integer overflow
body: <p>How to detect integer overflow in D? (check carry flag?)</p>
  
  <p>Original example:</p>
  
  <pre><code>ubyte a = 100;
  ubyte b = 200;
  ubyte c = a + b;
  // c can't represent 300; how to detect the overflow now?
  </code></pre>
  
  <p>Revised example:</p>
  
  <pre><code>uint a = 2_000_000_000;
  uint b = 3_000_000_000;
  uint c = a + b;
  // c can't represent 5_000_000_000; how to detect the overflow now?
  </code></pre>
  
  <p>Also with multiplication and pre/post-increment.</p>