How to forward declare a class under a namespace in c++, such as std::string?
<blockquote>
  <p><strong>Possible Duplicates:</strong><br>
  <a href="http://stackoverflow.com/questions/920731/c-removing-includevector-or-includestring-in-class-header">C++, removing #include&lt;vector&gt; or #include&lt;string&gt; in class header</a><br>
  <a href="http://stackoverflow.com/questions/307343/forward-declare-an-stl-container">Forward declare an STL container?</a>  </p>
</blockquote>



<p>I want to forward declare std::string, by the way, can I forward declare a struct?</p>
