From: Matthijs Kooijman <m.kooijman@student.utwente.nl>
Date: Wed, 19 Aug 2009 12:35:06 +0000 (+0200)
Subject: Add mapAccumLM helper function.
X-Git-Url: https://git.stderr.nl/gitweb?a=commitdiff_plain;h=7d3ab3315462e18a84e6d0312dd3c444292e43bb;p=matthijs%2Fmaster-project%2Fc%CE%BBash.git

Add mapAccumLM helper function.
---

diff --git "a/c\316\273ash/CLasH/Utils.hs" "b/c\316\273ash/CLasH/Utils.hs"
index 822bd55..94da854 100644
--- "a/c\316\273ash/CLasH/Utils.hs"
+++ "b/c\316\273ash/CLasH/Utils.hs"
@@ -50,3 +50,10 @@ isJustM = Monad.liftM Maybe.isJust
 andM, orM :: (Monad m) => m [Bool] -> m Bool
 andM = Monad.liftM and
 orM = Monad.liftM or
+
+mapAccumLM :: (Monad m) => (acc -> x -> m (acc, y)) -> acc -> [x] -> m (acc, [y])
+mapAccumLM _ s []        =  return (s, [])
+mapAccumLM f s (x:xs)    =  do
+  (s',  y ) <- f s x
+  (s'', ys) <- mapAccumLM f s' xs
+  return (s'', y:ys)