title: How to declare concept function signature with a template type?
body: <p>Is there a way to have a concept function signature that has a template argument?</p>
  <p>Something like this:</p>
  <pre class="lang-cpp prettyprint-override"><code>template&lt;typename SomeTypeT, typename U&gt;
  concept SomeType = requires(SomeTypeT s) {
      { s.SomeFunction&lt;U&gt;() };
  };
  </code></pre>
  <p>?</p>