NS_NOTYETIMPLEMENTED("write me!"); return NS_ERROR_NOT_IMPLEMENTED;
NS_PRECONDITION(aNextSibling != nsnull, "null ptr"); if (! aNextSibling) return NS_ERROR_NULL_POINTER;  *aNextSibling = nsnull; return NS_OK;
XULDocumentImpl::GetNextSibling(nsIDOMNode** aNextSibling){    NS_NOTYETIMPLEMENTED("write me!");    return NS_ERROR_NOT_IMPLEMENTED;}