diff --git a/a4/db.txt b/a4/db.txt
deleted file mode 100644
index e69de29..0000000
diff --git a/a4/src/APL/InterpIO.hs b/a4/src/APL/InterpIO.hs
index 5706c91..89c8d06 100644
--- a/a4/src/APL/InterpIO.hs
+++ b/a4/src/APL/InterpIO.hs
@@ -78,7 +78,12 @@ runEvalIO evalm = do
       case result of
         Right s -> case (lookup key s) of
           Just val -> runEvalIO' r db $ k val
-          Nothing ->  pure $ Left "Cannot find key :)"
+          Nothing ->  do
+            input <- prompt $ "Invalid key: "++(show key)++". Enter a replacement: "
+            let val = readVal input
+            case val of
+              Just v -> runEvalIO' r db $ (Free (KvGetOp v k))
+              Nothing -> pure $ Left $ "Invalid key: "++input
         Left e -> pure $ Left e
     runEvalIO' r db (Free (KvPutOp key val m)) = do
       result <- readDB db
diff --git a/a4/src/APL/Interp_Tests.hs b/a4/src/APL/Interp_Tests.hs
index e190e88..d7ba523 100644
--- a/a4/src/APL/Interp_Tests.hs
+++ b/a4/src/APL/Interp_Tests.hs
@@ -139,11 +139,35 @@ ioTests =
         r <- evalIO' (Let "_" (KvPut (CstInt 1) (CstInt 2)) (KvGet (CstInt 1)))
         r @?= Right (ValInt 2),
       --
+      testCase "KvGetOp Bool" $ do
+        r <- evalIO' (Let "_" (KvPut (CstBool True) (CstBool False)) (KvGet (CstBool True)))
+        r @?= Right (ValBool False),
+      --
       testCase "KvGetOp shadowing" $ do
         r <- evalIO' (Let "_" (KvPut (CstInt 1) (CstInt 2)) (Let "_" (KvPut (CstInt 1) (CstInt 3)) (KvGet (CstInt 1))))
         r @?= Right (ValInt 3),
       --
       testCase "KvGetOp fail" $ do
-        r <- evalIO' (KvGet (CstInt 1))
-        r @?= Left "Cannot find key :)"
+        (_, r) <-
+          captureIO [":)"] $
+            evalIO' (KvGet (CstInt 1))
+        r @?= Left "Invalid key: :)",
+      --
+      testCase "KvGetOp invalid int" $ do
+        (_, r) <-
+          captureIO ["ValInt 1"] $
+            evalIO' (Let "_" (KvPut (CstInt 1) (CstInt 2)) (KvGet (CstInt 3)))
+        r @?= Right (ValInt 2),
+      --
+      testCase "KvGetOp invalid bool" $ do
+        (_, r) <-
+          captureIO ["ValBool True"] $
+            evalIO' (Let "_" (KvPut (CstBool True) (CstInt 2)) (KvGet (CstInt 3)))
+        r @?= Right (ValInt 2),
+      --
+      testCase "KvGetOp invalid multiple" $ do
+        (_, r) <-
+          captureIO ["ValInt 1","ValInt 2","ValInt 3"] $
+            evalIO' (Let "_" (KvPut (CstInt 3) (CstInt 2)) (KvGet (CstInt 4)))
+        r @?= Right (ValInt 2)
     ]