*aItem = mRangeList->mRangeArray->ElementAt(mIndex); return NS_OK;
nsCOMPtr<nsISupports> indexIsupports = dont_AddRef(mRangeList->mRangeArray->ElementAt(mIndex)); return indexIsupports->QueryInterface(nsIDOMRange::GetIID(),(void **)aItem);
nsRangeListIterator::CurrentItem(nsISupports **aItem){  if (!aItem)    return NS_ERROR_NULL_POINTER;  PRUint32 cnt;  nsresult rv = mRangeList->mRangeArray->Count(&cnt);  if (NS_FAILED(rv)) return rv;  if (mIndex >=0 && mIndex < (PRInt32)cnt){    *aItem = mRangeList->mRangeArray->ElementAt(mIndex);    return NS_OK;  }  return NS_ERROR_FAILURE;}