title: Behaviour of std::list:begin() when list is empty
body: <p>Does the following give defined results in terms of the C++ standard?</p>
  
  <pre><code>std::list&lt;int&gt; myList;
  std::list&lt;int&gt;::iterator myIter = myList.begin();    // any issues?
  myList.push_back( 123 );
  myIter++;                                  // will myIter point to the 123 I pushed?
  </code></pre>
  
  <p>I can test this out on the compiler I'm using... but I'd like a more definitive answer.    </p>