From 3be88ad6b52ad380ae1c10dc42a633a9851c376a Mon Sep 17 00:00:00 2001
From: Simon Michael <simon@joyful.com>
Date: Tue, 13 Oct 2015 11:49:51 -0700
Subject: [PATCH] simplify combineJournalUpdates

I really don't see why that extra x parameter is needed or works..
rewrite it in simpler form.

I also might be introducing breakage for older GHC's by using
unconditionally <$>, but I'm not seeing that for some reason
(tested back to ghc 7.6).
---
 hledger-lib/Hledger/Read/JournalReader.hs | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/hledger-lib/Hledger/Read/JournalReader.hs b/hledger-lib/Hledger/Read/JournalReader.hs
index ec3861c57..225d8ce04 100644
--- a/hledger-lib/Hledger/Read/JournalReader.hs
+++ b/hledger-lib/Hledger/Read/JournalReader.hs
@@ -101,10 +101,14 @@ parse _ = parseJournalWith journal
 genericSourcePos :: SourcePos -> GenericSourcePos
 genericSourcePos p = GenericSourcePos (sourceName p) (sourceLine p) (sourceColumn p)
 
--- | Flatten a list of JournalUpdate's into a single equivalent one.
+-- | Flatten a list of JournalUpdate's (journal-transforming
+-- monadic actions which can do IO or raise an exception) into a
+-- single equivalent action.
 combineJournalUpdates :: [JournalUpdate] -> JournalUpdate
 combineJournalUpdates us = liftM (foldl' (\acc new x -> new (acc x)) id) $ sequence us
 -- XXX may be contributing to excessive stack use
+--combineJournalUpdates us = foldl' (flip (.)) id <$> sequence us
+
 -- cf http://neilmitchell.blogspot.co.uk/2015/09/detecting-space-leaks.html
 -- $ ./devprof +RTS -K576K -xc
 -- *** Exception (reporting due to +RTS -xc): (THUNK_STATIC), stack trace: