NS_IMETHOD Advance() { nsresult rc = NS_ERROR_FAILURE; if( mCurrent) { mCurrent = mCurrent->GetNext(); if( mCurrent) rc = NS_OK; } return rc; }
NS_IMETHODIMP nsFontSizeIterator::Advance() { if (nsnull != mFontInfo->mSizes && mFontInfo->mSizes->Count() > 0 && mSizeIterInx < mFontInfo->mSizes->Count()-2) { mSizeIterInx++; return NS_OK; }  return NS_ERROR_FAILURE; }
   NS_IMETHOD Advance()   {      nsresult rc = NS_ERROR_FAILURE;      if( mCurrent)      {         mCurrent = mCurrent->GetNext();         if( mCurrent) rc = NS_OK;      }      return rc;   }