From 091acfa8480a4726bd279feb689944b7d1fd3f2e Mon Sep 17 00:00:00 2001
From: Neil Brown <neil@twistedsquare.com>
Date: Sat, 7 Feb 2009 18:45:56 +0000
Subject: [PATCH] Added a new helper function to Utils for joining pairs of
 lists with pairs of lists

---
 checks/ArrayUsageCheck.hs | 2 +-
 common/Utils.hs           | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/checks/ArrayUsageCheck.hs b/checks/ArrayUsageCheck.hs
index 93ee02f..85251d1 100644
--- a/checks/ArrayUsageCheck.hs
+++ b/checks/ArrayUsageCheck.hs
@@ -418,7 +418,7 @@ makeSingleEq f e desc = (lift (flatten e) >>* f) >>= makeEquation e ([{-TODO-}],
 
 -- | A helper function for joining two problems
 accumProblem :: (EqualityProblem,InequalityProblem) -> (EqualityProblem,InequalityProblem) -> (EqualityProblem,InequalityProblem)
-accumProblem (a,b) (c,d) = (a ++ c, b ++ d)
+accumProblem = concatPair
 
 
 -- | Given a list of (written,read) expressions, an expression representing the upper array bound, returns either an error
diff --git a/common/Utils.hs b/common/Utils.hs
index acf572b..46569df 100644
--- a/common/Utils.hs
+++ b/common/Utils.hs
@@ -117,6 +117,10 @@ combineCompare (LT:_) = LT
 combineCompare (GT:_) = GT
 combineCompare (EQ:os) = combineCompare os
 
+-- Takes two pairs of lists, returns a pair with the fsts join and the snds joined
+concatPair :: ([a], [b]) -> ([a], [b]) -> ([a], [b])
+concatPair a b = (fst a ++ fst b, snd a ++ snd b)
+
 -- | Maps two functions over members of a pair
 transformPair :: (x -> a) -> (y -> b) -> (x,y) -> (a,b)
 transformPair f g (x,y) = (f x, g y)