From 81a27334bdf38fbad6d4e8804abbf0c7db5fac7b Mon Sep 17 00:00:00 2001
From: pimjager <pim@pimjager.nl>
Date: Tue, 21 Jun 2016 11:12:04 +0200
Subject: [PATCH] Fixed checking of lists

---
 examples/old/quickTest.spl |  7 +++++++
 sem.icl                    | 15 +++++++++++----
 2 files changed, 18 insertions(+), 4 deletions(-)
 create mode 100644 examples/old/quickTest.spl

diff --git a/examples/old/quickTest.spl b/examples/old/quickTest.spl
new file mode 100644
index 0000000..da99ac4
--- /dev/null
+++ b/examples/old/quickTest.spl
@@ -0,0 +1,7 @@
+main() {
+    
+    var xs = [2];
+    var ys = [1, True];
+    var ls = [1, 2, True, 'a'];
+
+}
\ No newline at end of file
diff --git a/sem.icl b/sem.icl
index a65bef6..eef2974 100644
--- a/sem.icl
+++ b/sem.icl
@@ -199,11 +199,11 @@ unify t1 t2=:(IdType tv)    | t1 == (IdType tv) = Right zero
                             | otherwise = Right $ 'Map'.singleton tv t1
 unify t1=:(IdType tv) t2 = unify t2 t1
 unify (ta1->>ta2) (tb1->>tb2) = unify ta1 tb1 >>= \s1->
-                                unify ta2 tb2 >>= \s2->
-                                Right $ compose s1 s2
+                                unify (subst s1 ta2) (subst s1 tb2) >>= \s2->
+                                Right $ compose s2 s1
 unify (TupleType (ta1,ta2)) (TupleType (tb1,tb2)) = unify ta1 tb1 >>= \s1->
                                                     unify ta2 tb2 >>= \s2->
-                                                    Right $ compose s1 s2
+                                                    Right $ compose s2 s1
 unify (ListType t1) (ListType t2) = unify t1 t2
 unify (FuncType t1) (FuncType t2) = unify t1 t2
 unify t1 t2 | t1 == t2  = Right zero
@@ -269,21 +269,26 @@ instance infer Expr where
         let given = t1 ->> t2 ->> tv in 
         op2Type op >>= \expected ->
         lift (unify expected given) >>= \s3 ->
+        applySubst s3 >>|
         pure ((compose s3 $ compose s2 s1), subst s3 tv, Op2Expr p e1_ op e2_)
 
     Op1Expr p op e1 =
         infer e1 >>= \(s1, t1, e1_) -> 
+        applySubst s1 >>|
         fresh >>= \tv ->
         let given = t1 ->> tv in 
         op1Type op >>= \expected ->
         lift (unify expected given) >>= \s2 ->
+        applySubst s2 >>|
         pure (compose s2 s1, subst s2 tv, Op1Expr p op e1)
 
-    EmptyListExpr _ = (\tv->(zero,tv,e)) <$> fresh
+    EmptyListExpr _ = (\tv->(zero,ListType tv,e)) <$> fresh
 
     TupleExpr p (e1, e2) = 
         infer e1 >>= \(s1, t1, e1_) -> 
+        applySubst s1 >>|
         infer e2 >>= \(s2, t2, e2_) ->
+        applySubst s2 >>|
         pure (compose s2 s1, TupleType (t1,t2), TupleExpr p (e1_,e2_))
 
     LambdaExpr _ _ _ = liftT $ Left $ Error "PANIC: lambdas should be Unfolded"
@@ -292,6 +297,7 @@ instance infer Expr where
         lookup f >>= \expected ->
         let accST = (\(s,ts,es) e->infer e >>= \(s_,et,e_)-> pure (compose s_ s,ts++[et],es++[e_])) in
         foldM accST (zero,[],[]) args >>= \(s1, argTs, args_)->
+        applySubst s1 >>|
         (case f of
             "print" = case head argTs of
                 IntType = pure "1printint"
@@ -306,6 +312,7 @@ instance infer Expr where
                 //TODO: Fieldselectors!
             _ = (let given = foldr (->>) tv argTs in
                 lift (unify expected given) >>= \s2->
+                applySubst s2 >>|
                 let fReturnType = subst s2 tv in
                 foldM foldFieldSelectors fReturnType fs >>= \returnType ->
                 pure (compose s2 s1, returnType, FunExpr p newF args_ fs))
-- 
2.20.1