X-Git-Url: https://ruin.nu/git/?a=blobdiff_plain;f=Typecheck.hs;h=922264061337362de5dab48dcbdb8163b9bee8d4;hb=93b042040034d199c925248a2dd1c321773ab6d0;hp=cc416e28d8f166dbfc62cf7adc551ccfffad61a3;hpb=a05f5aee2ceddec9721ce04ae596734524b80940;p=proglang.git

diff --git a/Typecheck.hs b/Typecheck.hs
index cc416e2..9222640 100644
--- a/Typecheck.hs
+++ b/Typecheck.hs
@@ -1,29 +1,73 @@
 module Typecheck where 
 
 import Abssyntax
+import Control.Monad.State
+import Data.Map as Map
+import Prelude hiding (lookup)
 
-typeCheckExp :: Exp -> Maybe Type
-BExp e o e' = do
-	TInt <- typeCheck e
-	TInt <- typeCheck e'
+
+type Types = Map Ident Type
+
+typeCheckExp :: (MonadState Types m) => Exp -> m Type
+typeCheckExp (BExp e o e') = do
+	TInt <- typeCheckExp e
+	TInt <- typeCheckExp e'
 	return TBool
-OpExp e o e' = do
-	TInt <- typeCheck e
-	TInt <- typeCheck e'
+typeCheckExp (OpExp e o e') = do
+	TInt <- typeCheckExp e
+	TInt <- typeCheckExp e'
+	return TInt
+typeCheckExp (EVar i) = typeCheckVar i
+typeCheckExp (EAss i e) = do
+	a <- typeCheckVar i
+	b <- typeCheckExp e
+	if a == b then return a else fail "FEL!"
+typeCheckExp (EInt i) = return TInt
+typeCheckExp (EBool b) = return TBool
+typeCheckExp EReadI = return TInt
+typeCheckExp EReadB = return TBool
+typeCheckExp (ExpT t e) = do
+	t2 <- typeCheckExp e
+	if t == t2 then return t else fail "FEL!"
+typeCheckExp EDefault = return NoType
+typeCheckExp (EPost i op) = do
+	TInt <- typeCheckVar i
 	return TInt
+typeCheckExp (ENeg e) = do
+	TInt <- typeCheckExp e
+	return TInt
+
 
-typeCheckStm :: Stm -> Maybe Type
-SNoop = return NoType
-SExp e = typeCheckExp e
-SBlock ss = do 
+typeCheckVar :: (MonadState Types m) => Ident -> m Type 
+typeCheckVar i = do
+	e <- get
+	lookup i e
+
+typeCheckStm :: (MonadState Types m) => Stm -> m Type 
+typeCheckStm SNoop = return NoType
+typeCheckStm (SExp e) = do 
+	typeCheckExp e
+	return NoType
+typeCheckStm (SBlock ss) = do 
 	mapM typeCheckStm ss
 	return NoType
-SIf e s s' = do
+typeCheckStm (SIf e s s') = do
 	TBool <- typeCheckExp e
 	NoType <- typeCheckStm s
 	NoType <- typeCheckStm s
 	return NoType
-SWhile e s = do
+typeCheckStm (SWhile e s) = do
 	TBool <- typeCheckExp e
 	NoType <- typeCheckStm s
+	return NoType
+typeCheckStm (SDecl t i e) = do
+	t2 <- typeCheckExp e
+	if t == t2 || t2 == NoType then do
+		m <- get
+		put (insert i t m)
+		return NoType
+		else fail $ "Illegal to assign an expression of type "++show t2++" to variable "++show i++" of type "++show t
+typeCheckStm (SPrint e) = do
+	typeCheckExp e
+	return NoType