title: Expand a type N times in template parameter
body: <p>I have the following problem:</p>
  
  <pre><code>template&lt; std::size_t N &gt;
  class A
  {
    std::function&lt; std::size_t( /*std::size_t,....,std::size_t &lt;- N-times*/) &gt; foo;
  };
  </code></pre>
  
  <p>As you can see above, I try to declare an <code>std::function&lt;...&gt; foo</code> as a member of a class <code>A</code>. Here, I want foo to have the return type <code>std::size_t</code> (which is no problem) and as input, I will pass N-times the type <code>std::size_t</code> but I don't know how. Is there any possibility?</p>
  
  <p>Many thanks in advance.</p>