title: Is const_cast safe?
body: <p>I can't find much information on <code>const_cast</code>.  The only info I could find (on Stack Overflow) is:</p>
  
  <blockquote>
    <p>The <code>const_cast&lt;&gt;()</code> is used to add/remove const(ness) (or volatile-ness) of a variable.</p>
  </blockquote>
  
  <p>This makes me nervous.  Could using a <code>const_cast</code> cause unexpected behavior?  If so, what?</p>
  
  <p>Alternatively, when is it okay to use <code>const_cast</code>?</p>