start of code generation

[cc1516.git] / sem.icl

diff --git a/sem.icl b/sem.icl
index 082cfe9..68b804d 100644 (file)
--- a/sem.icl
+++ b/sem.icl
@@ -270,10 +270,13 @@ instance infer Stmt where
         pure (compose s3 $ compose s2 s1, subst s3 wht)
 
     AssStmt (VarDef k fs) e =
-        infer e >>= \(s1, et)->
-        applySubst s1 >>|
-        changeGamma (extend k (Forall [] et)) >>| //todo: fieldselectors
-        pure (s1, VoidType)
+        lookup k >>= \expected ->
+        infer e >>= \(s1, given)->
+        lift (unify expected given) >>= \s2->
+        let s = compose s2 s1 in
+        applySubst s >>|
+        changeGamma (extend k (Forall [] given)) >>| //todo: fieldselectors
+        pure (s, VoidType)
 
     FunStmt f es = undef //what is this? 
 
@@ -345,25 +348,6 @@ instance type [a] | type a where
         applySubst (compose s2 s1) >>|
         pure (compose s2 s1, [v_:vs_])
 
-//        mapM processGamma dcls//
-
-////add the infered type in Gamma to AST constructs
-//class processGamma a :: a -> Typing a//
-
-//instance processGamma VarDecl where
-//    processGamma v=:(VarDecl p _ k e) = 
-//        gamma >>= \g -> case 'Map'.member k g of
-//            False = undef
-//            True  = instantiate ('Map'.find k g) >>= \t->
-//                    pure (VarDecl p (Just t) k e)//
-
-//instance processGamma FunDecl where
-//    processGamma v=:(FunDecl p k args _ vds stmts) = 
-//        gamma >>= \g -> case 'Map'.member k g of
-//            False = undef
-//            True  = instantiate ('Map'.find k g) >>= \t->
-//                    pure (FunDecl p k args (Just t) vds stmts) 
-
 introduce :: String -> Typing Type
 introduce k = 
     fresh >>= \tv ->