title: std::holds_alternative variadic template
body: <p>Is it possible to wrap a <code>std::holds_alternative</code> to a variadic template to use it with more types?</p>
  
  <p>For example:</p>
  
  <pre><code>std::variant&lt;bool, int, double, std::string&gt; var = 4;
  bool r = std::holds_alternative&lt;bool, double&gt;(var); // holds either bool or double
  </code></pre>