title: return type of public IEnumerator GetEnumerator()?
body: <p>To implement collection, I have to complete GeEnumerator(). But the return type of this function is IEnumerator. How can it be done ?
  For example..</p>
  
  <pre><code>class MyList : IEnumerable, IEnumerator
  {
      private int[] array;
      int positino = -1;        
      public IEnumerator GetEnumerator()
      {
          for(int i = 0 ; i &lt; array.Length; ++i)
          {
                yield return array[i];
          }
      }
  }
  </code></pre>
  
  <p>array[i] is integer not IEnumerator type. How can this function return integer?    </p>