title: How to alias, declare, and initiate all together
body: <p>I have cases which I make an alias to specific template instance.
  In my code previous to c++11, it was, for example:</p>
  
  <pre><code>typedef std::vector&lt;std::string&gt; My;
  </code></pre>
  
  <p>But I want to use the new language capabilities for making only one instance.
  That would be:</p>
  
  <pre><code>template class std::vector&lt;std::string&gt;;//in source file
  extern template class std::vector&lt;std::string&gt;;//in header file
  using My = std::vector&lt;std::string&gt;;//in header file
  </code></pre>
  
  <p>I have a long list of such typedef's in one header file (they are all in same context). Is there a way to do it without repeating each template 3 times?</p>