Type system progress on bus design

bs/Bus.bs

@@ -3,5 +3,18 @@ package Bus(a) where
 import Types
 import BusTypes
 
+interface (TestType :: * -> *) t = {}
+    -- doSomething :: t -> Action
+
+mkTestType :: (Bits t n, Arith t, Eq t) => Module (TestType t)
+mkTestType = do
+    return $ interface TestType {}
+
+mkTestTop :: Module Empty
+mkTestTop = do
+    testType :: TestType (UInt 5)
+    testType <- mkTestType
+    return $ interface Empty { }
+
 a :: UInt 5
 a = 3