title: Lambda function with number of arguments determined at compile-time
body: <p>I would like to declare a lambda function with exactly N parameters, where N is a template argument. Something like...</p>
  
  <pre><code>template &lt;int N&gt;
  class A {
      std::function&lt;void (double, ..., double)&gt; func;
                          // exactly n inputs
  };
  </code></pre>
  
  <p>I could not think of a way to do this with the metafunction paradigm.</p>