title: std::string::back()
body: <p>Why isn't there a <code>std::basic_string&lt;...&gt;::back()</code> member function?</p>
  
  <p>The functionality is obviously there, I mean, one can write</p>
  
  <ul>
  <li><p><code>myString[myString.size()-1]</code>  </p></li>
  <li><p><code>*myString.rbegin()</code> </p></li>
  </ul>
  
  <p>Am I assuming some wrong equivalence between the potential <code>back()</code> and the two methods above? You can say that my second version is concise enough, but then, why not provide a function which is trivial to implement which brings string one step closer to a container? Is there a caveat I am missing?</p>
  
  <p>Thanks.     </p>