title: Can't access public classes in an other project but the same namespace
body: <p>I have two projects in my solution and in each of them I have a CS file containing a public class. Since both classes are in the same namespace, I was expecting them to be able to see each other. That is not the case. See the setup below.</p>
  
  <p>Project Woof1, file File.CS</p>
  
  <pre><code>namespace MyNameSpace
  {
    public class Foo
    {
      // Doesn't compile
      Faa f;
    }
  }
  </code></pre>
  
  <p>Project Woof2, file File.CS</p>
  
  <pre><code>namespace MyNameSpace
  {
    public class Faa
    {
      // Doesn't compile
      Foo f;
    }
  }
  </code></pre>
  
  <p>NB, both classes are stored in files with the same name <strong>but</strong> in different directories (i.e. not the same file).</p>
  
  <ol>
  <li>Why can't I compile it?</li>
  <li>What can I do about it (except moving the classes to the same project).</li>
  </ol>
  
  <p><em>(I only found <a href="https://stackoverflow.com/questions/7040123/namespace-not-available-in-other-project">this discussion</a> on the subject but in the end it wasn't really my issue.)</em></p>