title: Accessing an enum in a namespace
body: <p>In a header I have a setup like this</p>
  
  <pre><code>namespace NS {
      typedef enum { GOOD, BAD, UGLY }enum_thing;
      class Thing {
          void thing(enum_thing elem);
      }
  }
  </code></pre>
  
  <p>and of course another cpp file that goes along with that header. Then I have a thread cpp file that contains main(). In this cpp file I use that enum to pass to the method thing().</p>
  
  <pre><code>using namespace NS;
  int main() {
      Thing t();
      t.thing(BAD);
  }
  </code></pre>
  
  <p>and of course I get other errors from G++ saying BAD was not declared. Any help on how I could overcome this error?</p>