write output to file (if -o), cmd line parser, handle dup imports

src/Lib/TopContext.idr

@@ -19,11 +19,11 @@ lookup nm top = go top.defs
 export
 covering
 Show TopContext where
-  show (MkTop defs metas _ _) = "\nContext:\n [\{ joinBy "\n" $ map show defs}]"
+  show (MkTop defs metas _ _ _) = "\nContext:\n [\{ joinBy "\n" $ map show defs}]"
 
 public export
 empty : HasIO m => m TopContext
-empty = pure $ MkTop [] !(newIORef (MC [] 0)) False !(newIORef [])
+empty = pure $ MkTop [] !(newIORef (MC [] 0)) False !(newIORef []) []
 
 ||| set or replace def. probably need to check types and Axiom on replace
 public export

src/Lib/Types.idr

@@ -342,6 +342,8 @@ record TopContext where
   metas : IORef MetaContext
   verbose : Bool
   errors : IORef (List Error)
+  ||| loaded modules
+  loaded : List String
 
 
 -- we'll use this for typechecking, but need to keep a TopContext around too.