use string for module names

src/Lib/TopContext.newt

@@ -34,7 +34,7 @@ lookupRaw raw top =
     Just entry => Just entry
     Nothing => go top.imported
   where
-    go : List (List String) → Maybe TopEntry
+    go : List String → Maybe TopEntry
     go Nil = Nothing
     go (ns :: nss) = case lookupMap' ns top.modules of
       Nothing => go nss
@@ -47,7 +47,7 @@ instance Show TopContext where
   show top = "\nContext:\n [\{ joinBy "\n" $ map (show ∘ snd) $ toList top.defs}]"
 
 emptyTop : TopContext
-emptyTop = MkTop emptyMap Nil emptyMap Nil emptyMap (MC emptyMap Nil 0 CheckAll) 0 Nil emptyMap
+emptyTop = MkTop emptyMap Nil emptyMap "" emptyMap (MC emptyMap Nil 0 CheckAll) 0 Nil emptyMap
 
 
 setFlag : QName → FC → EFlag → M Unit