X-Git-Url: https://ruin.nu/git/?a=blobdiff_plain;f=Typecheck.hs;h=1b0baa00ed5d48dc760f029f9759e8bb821eed9c;hb=9625a8a7eb7aebeb161ca15cf66cff5699f89103;hp=cdba298976ad2aefcecaf7e71a52b74ebb6415f0;hpb=fe6d5e0ac088e6b648a5029b101402c017fd04de;p=proglang.git

diff --git a/Typecheck.hs b/Typecheck.hs
index cdba298..1b0baa0 100644
--- a/Typecheck.hs
+++ b/Typecheck.hs
@@ -1,4 +1,4 @@
-module Typecheck (typeCheckExp, typeCheckStm, typeCheckVar) where 
+module Typecheck (typeCheck,typeCheckExp, typeCheckStm, typeCheckVar) where 
 
 
 import Abssyntax
@@ -16,6 +16,9 @@ assert :: Monad m => Bool -> String -> m ()
 assert True _ = return ()
 assert False s = fail s
 
+typeCheck :: [Stm] -> IO ()
+typeCheck s = runStateT (mapM typeCheckStm s) [empty] >> return ()
+
 typeCheckExp :: (MonadState Types m) => Exp -> m Type
 typeCheckExp (BiOpExp e o e') = do
 	t1 <- typeCheckExp e
@@ -75,13 +78,18 @@ typeCheckStm (SIf e s s') = do
 typeCheckStm (SWhile e s) = do
 	TBool <- typeCheckExp e
 	pushAndPop $ typeCheckStm s
+typeCheckStm (SDeclD t i) = addVariable i t
 typeCheckStm (SDecl t i e) = do
 	t2 <- typeCheckExp e
 	assert (t == t2) $ "Illegal to assign an expression of type "++show t2++" to variable "++show i++" of type "++show t
+	addVariable i t
+typeCheckStm (SPrint e) = do
+	typeCheckExp e
+	return ()
+
+addVariable :: (MonadState Types m) => Ident -> Type -> m ()
+addVariable i t = do
 	(m:ms) <- get
 	case insertLookupWithKey (\k a1 a2 -> a1) i t m of
 		(Nothing,m') -> put (m':ms)
 		_ -> fail $ "Duplicate variable declaration: "++show i
-typeCheckStm (SPrint e) = do
-	typeCheckExp e
-	return ()