title: In C++ what does template<> mean?
body: <p>It's not a syntax I'm familiar with, but I saw it in <a href="https://stackoverflow.com/questions/2454905/force-type-of-c-template/2458547#2458547">another question</a>, an example being:</p>
  
  <pre><code>template&lt;&gt; struct Allowed&lt;std::string&gt; { };
  </code></pre>
  
  <p>What does <code>template&lt;&gt;</code> actually mean, with no template type/parameter?</p>