title: What is "template<class T> using owner = T;"?
body: <p>Below is excerpted from <code>gsl.h</code> of Microsoft's <code>gsl</code> library (<a href="https://github.com/microsoft/gsl" rel="nofollow">https://github.com/microsoft/gsl</a>):</p>
  
  <pre><code>namespace gsl
  {
      //
      // GSL.owner: ownership pointers 
      //
      using std::unique_ptr;
      using std::shared_ptr;
  
      template&lt;class T&gt;
      using owner = T;
      ...
  };
  </code></pre>
  
  <p>I cannot understand what the following alias template means:</p>
  
  <pre><code>template&lt;class T&gt;
  using owner = T;
  </code></pre>
  
  <p>Any explanations?</p>