title: C++ replace base class in derived class
body: <p>I believe I'm thinking about this "badly" (non-C++'y).  Here's what I'm trying to do</p>
  
  <pre><code>class AA {
      public:
          AA(const char* name, unsigned short number);
  
          int Write(int x);
      ...
      }
  
  class BB: public AA {
      public:
          BB(const char* name, unsigned short number, const char* other);
          BB(AA aaObj, const char* other);
  
          int Write(double y, int x) {
              /* do something */
              AA::Write(x)
              }
      ...
      }
  </code></pre>
  
  <p>On the second BB constructor I'd like to replace the base object of BB with aaObj.  I don't want a copy, I want the actual base object to the be same (same reference).</p>
  
  <p>Questions: </p>
  
  <ol>
  <li>Is this possible?  </li>
  <li>Is this a bad idea?  </li>
  <li>Is there a better pattern for this (factory producing objects with shared members?</li>
  </ol>