lit :: Parser Expr
lit =  (natural >>= (return . Lit . Int))
   <|> (bool    >>= (return . Lit . Bool))
   <|> (bool    >>= (return . Lit . Bool))
   <?> "lit"
lit :: Parser Expr
lit =  (natural >>= (return . Lit . Int))
   <|> (bool    >>= (return . Lit . Bool))
   <|> (bool    >>= (return . Lit . Bool))
   <?> "lit"
lit =  (natural >>= (return . Lit . Int))
   <|> (bool    >>= (return . Lit . Bool))
   <|> (bool    >>= (return . Lit . Bool))
   <?> "lit"