arseSpec :: Parser [Int]
parseSpec = do
  ranges <- sepBy1 parseRangeSpec (char ',')
  return $ foldr1 merge ranges

parseSpec :: Parser [Int]
parseSpec = do
  ranges <- sepBy1 parseRangeSpec (char ',')
  return $ foldr1 merge ranges
parseSpec = do
  ranges <- sepBy1 parseRangeSpec (char ',')
  return $ foldr1 merge ranges