From d5d29a4061d6ff573adb692b805c6eed9f324fc5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Janis=20Voigtl=C3=A4nder?=
 <jvoigtlaender@users.noreply.github.com>
Date: Thu, 21 Jan 2016 12:15:06 +0100
Subject: [PATCH] don't show the same unhandled pattern several times in error
 message

---
 src/Reporting/Error/Pattern.hs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/Reporting/Error/Pattern.hs b/src/Reporting/Error/Pattern.hs
index 72a583ad2..b6473c154 100644
--- a/src/Reporting/Error/Pattern.hs
+++ b/src/Reporting/Error/Pattern.hs
@@ -2,6 +2,7 @@
 module Reporting.Error.Pattern where
 
 import Text.PrettyPrint.ANSI.Leijen (text)
+import Data.List (nub)
 
 import qualified Nitpick.Pattern as Pattern
 import qualified Reporting.Error.Helpers as Help
@@ -61,7 +62,7 @@ unhandledError :: [Pattern.Pattern] -> String -> String
 unhandledError unhandledPatterns relevantMessage =
   let
     (visiblePatterns, rest) =
-      splitAt 4 unhandledPatterns
+      splitAt 4 (nub unhandledPatterns)
 
     patternList =
         map (Pattern.toString False) visiblePatterns