title: How do you use the non-default constructor for a member?
body: <p>I have two classes</p>
  <pre><code>class a {
      public:
          a(int i);
  };
  
  class b {
      public:
          b(); //Gives me an error here, because it tries to find constructor a::a()
          a aInstance;
  }
  </code></pre>
  <p>How can I get it so that <code>aInstance</code> is instantiated with <code>a(int i)</code> instead of trying to search for a default constructor?  Basically, I want to control the calling of <code>a</code>'s constructor from within <code>b</code>'s constructor.</p>