3a_asm: FIX: parser fail bei labels aufloesen

[calu.git] / 3a_asm / Expr_eval.hs

diff --git a/3a_asm/Expr_eval.hs b/3a_asm/Expr_eval.hs
index 1b12f4b7b3e1401287e286aa9d9f8ac4d18a7947..71e0f4de63ae06f083fde358ea8a9bb3a64c758f 100644 (file)
--- a/3a_asm/Expr_eval.hs
+++ b/3a_asm/Expr_eval.hs
@@ -1,4 +1,4 @@
-module Expr_eval (expr) where
+module Expr_eval (expr, testExpr) where
 
 import DTFormat
 
@@ -10,6 +10,7 @@ import qualified Text.ParserCombinators.Parsec.Token as P
 import Text.ParserCombinators.Parsec.Language
 import System.IO
 import Data.Word
+import Data.List
 import Data.Bits
 
 lexer :: P.TokenParser ()
@@ -17,7 +18,6 @@ lexer = P.makeTokenParser (haskellDef { reservedOpNames = ["*","/","+","-","<<",
 
 decimal = P.decimal lexer
 hexadecimal = P.hexadecimal lexer
-parens = P.parens lexer
 reservedOp = P.reservedOp lexer
 
 expr :: [DictElem] -> Parser Word32
@@ -48,16 +48,17 @@ factor_spaces d = do
 factor :: [DictElem] -> Parser Word32
 factor d =
        do {
-               parens (expr d);
+               char '('; r <- expr d; char ')';
+               return r
        } <|> do {
                -- define or label
                s <- foldl1 (<|>) (fmap (try . string . fst) d);
                return $ (get_elem s d)
-       } <|> do {
+       } <|> try (do {
                string "0";
                r <- hexadecimal;
                return $ fromInteger r
-       } <|> do {
+       } ) <|> do {
                r <- decimal;
                return $ fromInteger r
        } <?> "factor"