title: Can you have a "pointer to member" to a member of a union?
body: <p>All descriptions that I can find talk about "pointer to member" in the context of a class. Unions are very similar to structures, and in particular have members too. Can you have a pointer to those members too?</p>
  
  <p>E.g.</p>
  
  <pre><code>union x {
      int a;
      float b;
  };
  int x::*p = &amp;x::a;
  </code></pre>
  
  <p>I'm not talking about pointer to the union as a whole, pointers as members of a union, etc. <code>p</code> in the example above would really be an offset, obviously of size 0. I'd need this construct to answer <a href="https://stackoverflow.com/questions/14375558/select-an-union-member-depending-on-a-template-parameter">this question</a>.</p>