import Text.ParserCombinators.Parsec

mah = do
  char '{'
  res <- li
  char '}'
  return res

li = sepBy item (char ',')
item = sepBy foo (char ':')
foo = many (noneOf ",:\n")

-- If this is uncommented it won't compile
-- eol = char '\n'

pli :: String -> Either ParseError [[String]]
pli input = parse li "off" input

test = "{lhs: \"133 + 234\",rhs: \"367\",error: \"\",icc: false}"