From 9b566f2a63690b0adfcfd85d4b550bee46ad123e Mon Sep 17 00:00:00 2001
From: hasufell <hasufell@hasufell.de>
Date: Wed, 8 Oct 2014 22:07:37 +0200
Subject: [PATCH] Improve error handling

---
 Algorithms/ConvexHull.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Algorithms/ConvexHull.hs b/Algorithms/ConvexHull.hs
index ad864af..3a36703 100644
--- a/Algorithms/ConvexHull.hs
+++ b/Algorithms/ConvexHull.hs
@@ -30,6 +30,7 @@ lowestYC (a:b:vs)
 -- P0 and the x-axis.
 grahamSort :: [PT] -- ^ the points to sort
            -> [PT] -- ^ sorted points
+grahamSort [] = []
 grahamSort xs = p0 : sortBy (\a b
   -> noEqual a b                            .
        compare
@@ -59,7 +60,6 @@ grahamSort xs = p0 : sortBy (\a b
 grahamGetCH :: [PT] -> [PT]
 grahamGetCH vs = f . grahamSort $ vs
   where
-    f [] = []
     f (x:y:z:xs)
       | ccw x y z = x : f (y:z:xs)
       | otherwise = f (x:z:xs)