float :: Parser Double
float = sign <*> unsigned
  where
    unsigned = read . concat <$> sequence [some digit, string ".", some digit]
float :: Parser Double
float = sign <*> unsigned
  where
    unsigned = read . concat <$> sequence [some digit, string ".", some digit]
float = sign <*> unsigned
  where
    unsigned = read . concat <$> sequence [some digit, string ".", some digit]