From 71a86bdf12e889b31bdec2cbb6822c18214485f7 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Anders=20M=C3=B6rtberg?= <andersmortberg@gmail.com>
Date: Thu, 8 Jun 2017 09:46:27 +0200
Subject: [PATCH] Check if some names were shadowed while loading the file

---
 Main.hs | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/Main.hs b/Main.hs
index c41c03e..fba67a9 100644
--- a/Main.hs
+++ b/Main.hs
@@ -98,10 +98,19 @@ initLoop flags f hist = do
       putStrLn $ "Resolver failed: " ++ err
       runInputT (settings []) (putHistory hist >> loop flags f [] TC.verboseEnv)
     Right (adefs,names) -> do
+
       (merr,tenv) <- TC.runDeclss TC.verboseEnv adefs
       case merr of
         Just err -> putStrLn $ "Type checking failed: " ++ shrink err
-        Nothing  -> putStrLn "File loaded."
+        Nothing  -> do
+          putStrLn "File loaded."
+          -- After loading the file check if some definitions were shadowed:
+          let ns = map fst names
+              uns = nub ns
+              dups = ns \\ uns
+          unless (dups == []) $
+            putStrLn $ "Warning: the following definitions were shadowed [" ++
+                        intercalate ", " dups ++ "]"
       if Batch `elem` flags
         then return ()
         else -- Compute names for auto completion
-- 
2.34.1