title: In the Visual Studio debugger, you can view special 'variables' beginning with '$'. What are they?
body: <p>For instance, write a function such as:</p>
  
  <pre><code>void foo()
  {
      try
      {
          throw new Exception(@"whatever");
      }
      catch
      {
          int n=1; //put a breakpoint here
      }
  }
  </code></pre>
  
  <p>When the debugger is on the line in the catch block, typing <code>$exception</code> will show the exception information.</p>
  
  <p>Are there any more?  What are these things?  There seems to be no official documentation on them.  I've used <code>$exception</code> for quite a while, but was hoping there were others that, for example, would show the <a href="https://stackoverflow.com/questions/268048/can-i-find-out-the-return-value-before-returning-while-debugging-in-visual-studio">return value of a method</a>.</p>