From: Samir Benmendil <me@rmz.io>
Date: Tue, 23 Jan 2018 20:39:54 +0000 (+0000)
Subject: Add parsers for List, DottedList and Quoted
X-Git-Url: https://git.rmz.io/my-scheme.git/commitdiff_plain/ae8ff4666104497a9d6f1d89f044bbb202f10c71?ds=inline

Add parsers for List, DottedList and Quoted

Nothing really new here.
---

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