title: C++ invoke explicit template constructor
body: <p>Can you tell me how to invoke template constructor explicitly (in initializer list)?
  for example:</p>
  
  <pre><code>struct T { 
      template&lt;class&gt; T();
  };
  
  struct U {
      U() : t&lt;void&gt;() {} //does not work
      T t;
  };
  </code></pre>
  
  <p>thanks</p>