title: How to check if two template parameters are exactly the same?
body: <p><em>How do I modify the following function template so that it returns 42 if template parameters <code>T</code> and <code>U</code> are exactly the same type?</em></p>
  
  <pre><code>template&lt;typename T,typename U&gt;
  int Foo()
  {
    return 0;
  }
  </code></pre>