ny1 parseNot
  (q, vs, a) <- parseQuanForm
  return $ foldr (\_ acc -> Not acc) (foldr (Quantifier q) a vs) nots

parseQuan = do
  (q, vs, a
parseNQuan = do
  nots <- many1 parseNot
  (q, vs, a) <- parseQuanForm
  return $ foldr (\_ acc -> Not acc) (foldr (Quantifier q) a vs) nots
parseNQuan = do
  nots <- many1 parseNot
  (q, vs, a) <- parseQuanForm
  return $ foldr (\_ acc -> Not acc) (foldr (Quantifier q) a vs) nots