-module Typecheck (typeCheckExp, typeCheckStm, typeCheckVar, typeCheckFunction, addFunction, emptyState, State(..)) where
+module Typecheck (typeCheck, typeCheckExp, typeCheckStm, typeCheckVar, typeCheckFunction, addFunction, emptyState, State(..)) where
import Abssyntax
emptyState = State{variables=[empty], functions=(empty), function=(Ident "")}
-inList :: Eq a => a -> [a] -> Bool
-inList _ [] = False
-inList a (x:xs) = if a == x then True else inList a xs
-
assert :: Monad m => Bool -> String -> m ()
assert True _ = return ()
assert False s = fail s
+typeCheck :: [Func] -> [Stm] -> IO ()
+typeCheck fun st = do
+ runStateT (do mapM addFunction fun; mapM typeCheckFunction fun; mapM typeCheckStm st) emptyState
+ return ()
+
typeCheckExp :: (MonadState State m) => Exp -> m Type
typeCheckExp (BiOpExp e o e') = do
t1 <- typeCheckExp e
t2 <- typeCheckExp e'
assert (t1 == t2) "The parameters for the binary operator aren't equal"
- if inList o [Eq,NEq] then return TBool
+ if elem o [Eq,NEq] then return TBool
else do
assert (t1 == TInt) "The parameters need to be of type int"
- if inList o [Plus,Minus,Times,Div]
+ if elem o [Plus,Minus,Times,Div]
then return TInt
else return TBool
typeCheckExp (EVar i) = typeCheckVar i
state <- get
modify (\s -> s{variables=[empty], function=i})
mapM (\(Decl t i) -> addVariable i t) d
+ case last s of
+ (SReturn _) -> return ()
+ _ -> fail $ "Function "++show i++" doesn't end with return statement"
mapM typeCheckStm s
put state