title: Template Argument 2 is invalid
body: <p>I keep getting the following errors :</p>
  
  <pre><code>utils.h:22:39: error: template argument 4 is invalid
  utils.h:21:24: error: template argument 2 is invalid
  </code></pre>
  
  <p>When I try to compile :</p>
  
  <pre><code>class Words { 
      map &lt;string, *Words &gt; synonyms;  
      map &lt;string, map&lt;string, *Words&gt; &gt; translations; 
  };
  </code></pre>
  
  <p>I don't quite understand what makes it an invalid argument. The error arrow is pointing to the ">" symbols. The purpose of the class is to build a dictionary using AVL TreeMaps.</p>