X-Git-Url: https://git.rmz.io/my-scheme.git/blobdiff_plain/d9a59677ebd0595e060978abef79c376c27400eb..ae8ff4666104497a9d6f1d89f044bbb202f10c71:/app/Main.hs diff --git a/app/Main.hs b/app/Main.hs index 03dbb41..fb8294a 100644 --- a/app/Main.hs +++ b/app/Main.hs @@ -65,11 +65,31 @@ parseNumber = do toNum <- radix 'o' -> readOct 'b' -> readInt 2 (\x -> elem x "01") (read . (:[])) +parseList :: Parser LispVal +parseList = liftM List $ sepBy parseExpr spaces + +parseDottedList :: Parser LispVal +parseDottedList = do + head <- endBy parseExpr spaces + tail <- char '.' >> spaces >> parseExpr + return $ DottedList head tail + +parseQuoted :: Parser LispVal +parseQuoted = do + char '\'' + x <- parseExpr + return $ List [Atom "quote", x] + parseExpr :: Parser LispVal parseExpr = parseString - <|> parseCharacter <|> parseNumber <|> parseAtom + <|> try parseCharacter + <|> parseQuoted + <|> do char '(' + x <- try parseList <|> parseDottedList + char ')' + return x readExpr :: String -> String readExpr input = case parse parseExpr "lisp" input of