NS_PRECONDITION(nsnull != aInstancePtr, "null pointer");  if (nsnull == aInstancePtr) {
NS_PRECONDITION(nsnull != aInstancePtrResult, "null pointer"); if (nsnull == aInstancePtrResult) {
nsresult Text::QueryInterface(const nsIID& aIID, void** aInstancePtr){  NS_PRECONDITION(nsnull != aInstancePtr, "null pointer");    if (nsnull == aInstancePtr) {    return NS_ERROR_NULL_POINTER;  }  if (aIID.Equals(kIDOMTextIID)) {    *aInstancePtr = (void*) ((nsIDOMText*)this);    nsHTMLContent::AddRef();    return NS_OK;  }  if (aIID.Equals(kIDOMNodeIID)) {    *aInstancePtr = (void*) ((nsIDOMNode*)(nsHTMLContent*)this);    nsHTMLContent::AddRef();    return NS_OK;  }  if (aIID.Equals(kISupportsIID)) {    *aInstancePtr = (void*) ((nsISupports*)                             ((nsIHTMLContent*)                              ((nsHTMLContent*)this)));    nsHTMLContent::AddRef();    return NS_OK;  }    return nsHTMLContent::QueryInterface(aIID, aInstancePtr);}