Why is this a pointer
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  <p><strong>Possible Duplicate:</strong><br>
  <a href="http://stackoverflow.com/questions/645994/why-this-is-a-pointer-and-not-a-reference">Why &#39;this&#39; is a pointer and not a reference?</a>  </p>
</blockquote>



<p>Why is <code>this</code> a pointer, rather rhan reference?  Can it ever be <code>NULL</code>?</p>
