From 208551111adaf25d1aaa8c73e6cddb9ca5c78ea4 Mon Sep 17 00:00:00 2001
From: Edsko de Vries <edsko@well-typed.com>
Date: Thu, 12 Feb 2015 12:07:21 +0000
Subject: [PATCH] Add union operation to PSQ
---
cabal-install/Distribution/Client/Dependency/Modular/PSQ.hs | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/cabal-install/Distribution/Client/Dependency/Modular/PSQ.hs b/cabal-install/Distribution/Client/Dependency/Modular/PSQ.hs
index 7197cd3f84..db2e320cd3 100644
--- a/cabal-install/Distribution/Client/Dependency/Modular/PSQ.hs
+++ b/cabal-install/Distribution/Client/Dependency/Modular/PSQ.hs
@@ -57,7 +57,7 @@ casePSQ (PSQ xs) n c =
(k, v) : ys -> c k v (PSQ ys)
splits :: PSQ k a -> PSQ k (a, PSQ k a)
-splits = go id
+splits = go id
where
go f xs = casePSQ xs
(PSQ [])
@@ -92,3 +92,6 @@ null (PSQ xs) = S.null xs
toList :: PSQ k a -> [(k, a)]
toList (PSQ xs) = xs
+
+union :: PSQ k a -> PSQ k a -> PSQ k a
+union (PSQ xs) (PSQ ys) = PSQ (xs ++ ys)
--
GitLab