From d2fb80c516fc1ff0acd7337ce63bb0eca96cec8b Mon Sep 17 00:00:00 2001
From: Neil Brown <neil@twistedsquare.com>
Date: Wed, 8 Apr 2009 15:33:36 +0000
Subject: [PATCH] Added a foldM1 function to the Utils module

---
 common/Utils.hs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/common/Utils.hs b/common/Utils.hs
index f598878..fcfbe20 100644
--- a/common/Utils.hs
+++ b/common/Utils.hs
@@ -393,3 +393,8 @@ liftWrapStateT wrap m
        (x, st') <- lift $ wrap (runStateT m st)
        put st'
        return x
+
+-- The foldM equivalent of foldl1:
+foldM1 :: Monad m => (a -> a -> m a) -> [a] -> m a
+foldM1 f (x:xs) = foldM f x xs
+foldM1 _ [] = fail "Empty list in foldM1"