From acca5d89177125967ab19fc33dcc9f423f0e13ce Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 29 Feb 2016 09:33:38 -0500
Subject: [PATCH] Add runLeft/runRight conveniences.

---
 src/Data/Functor/Both.hs | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/Data/Functor/Both.hs b/src/Data/Functor/Both.hs
index 4593dfcae..a71eb2d13 100644
--- a/src/Data/Functor/Both.hs
+++ b/src/Data/Functor/Both.hs
@@ -10,6 +10,14 @@ newtype Both a = Both { runBoth :: (a, a) }
 both :: a -> a -> Both a
 both = curry Both
 
+-- | Runs the left side of a `Both`.
+runLeft :: Both a -> a
+runLeft = fst . runBoth
+
+-- | Runs the right side of a `Both`.
+runRight :: Both a -> a
+runRight = snd . runBoth
+
 zip :: Both [a] -> [Both a]
 zip = zipWith both