From fe6d5e0ac088e6b648a5029b101402c017fd04de Mon Sep 17 00:00:00 2001
From: Michael Andreen <harv@ruin.nu>
Date: Thu, 2 Mar 2006 20:41:09 +0000
Subject: [PATCH] introduced pushAndPop in the typechecker too

---
 Typecheck.hs | 22 ++++++++++------------
 1 file changed, 10 insertions(+), 12 deletions(-)

diff --git a/Typecheck.hs b/Typecheck.hs
index a78f8f0..cdba298 100644
--- a/Typecheck.hs
+++ b/Typecheck.hs
@@ -56,27 +56,25 @@ findVariable :: (MonadState Types m) => Ident -> Types -> m Type
 findVariable i [] = fail $ "Variable "++show i++" not found in any scope."
 findVariable i (m:ms) = if member i m then lookup i m else findVariable i ms
 
+pushAndPop :: (MonadState Types m) => m a -> m ()
+pushAndPop s = do
+	modify (empty:)
+	s
+	modify tail
+
 typeCheckStm :: (MonadState Types m) => Stm -> m ()
 typeCheckStm SNoop = return ()
 typeCheckStm (SExp e) = do 
 	typeCheckExp e
 	return ()
-typeCheckStm (SBlock ss) = do 
-	modify (empty:)
-	mapM typeCheckStm ss
-	modify tail
+typeCheckStm (SBlock ss) = pushAndPop $ mapM typeCheckStm ss
 typeCheckStm (SIf e s s') = do
 	TBool <- typeCheckExp e
-	modify (empty:)
-	typeCheckStm s
-	modify (\s -> empty:tail s)
-	typeCheckStm s'
-	modify tail
+	pushAndPop $ typeCheckStm s
+	pushAndPop $ typeCheckStm s'
 typeCheckStm (SWhile e s) = do
 	TBool <- typeCheckExp e
-	modify (empty:)
-	typeCheckStm s
-	modify tail
+	pushAndPop $ typeCheckStm s
 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
-- 
2.39.2