Update examples

testsuite/hier/hier4/C.hs

@@ -0,0 +1,12 @@
+
+-- try to construct an orphan module == an instance decl-only module,
+-- that uses classes and types not defined in this module
+
+module C (C) where
+
+import D
+
+instance C a => D (T a) where
+
+class C a where
+