title: What's the reason of this error (inheriting class whith generic)?
body: <p><a href="https://i.stack.imgur.com/vIn2Z.png" rel="nofollow noreferrer">Error screenshot</a>
  I'm creating a pack of generic classes, gradually specifying generic type from <strong>T</strong> to <strong>example_of_stored_class</strong>. </p>
  
  <pre><code>public class ModifiedList&lt;example_of_stored_class&gt; : AdvancedList&lt;example_of_stored_class&gt; 
  {
      public void someMethod ()
      {
      }
  }
  
  public class AdvancedList&lt;T&gt; : List&lt;T&gt; where T : example_of_stored_class
  {
      public AdvancedList ()
          {
  
          }
  }
  public class example_of_stored_class
  {
      public string s = "Hi, i'm an example_of_stored_class!";
  }
  </code></pre>
  
  <p>Error msg:</p>
  
  <blockquote>
    <p>The type 'example_of_stored_class' cannot be used as type parameter 'T' in the generic type or method 'AdvancedList'. There is no boxing conversion or type parameter conversion from 'example_of_stored_class' to <strong>'R7_app</strong>.example_of_stored_class'.</p>
  </blockquote>
  
  <p>The question is -  what's the difference between 'example_of_stored_class' and 'R7_app.example_of_stored_class'? Why it happens?</p>