From f2e20e3279db7d4817a10474e7e9fe0237746fcb Mon Sep 17 00:00:00 2001
From: Kazu Yamamoto <kazu@iij.ad.jp>
Date: Thu, 3 Jul 2014 14:26:39 +0900
Subject: [PATCH] comments.

---
 Language/Haskell/GhcMod/Monad.hs | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/Language/Haskell/GhcMod/Monad.hs b/Language/Haskell/GhcMod/Monad.hs
index 3a5a619..7457d72 100644
--- a/Language/Haskell/GhcMod/Monad.hs
+++ b/Language/Haskell/GhcMod/Monad.hs
@@ -26,12 +26,18 @@ import Exception
 import GHC
 import GHC.Paths (libdir)
 import GhcMonad
-import MonadUtils
 #if __GLASGOW_HASKELL__ <= 702
 import HscTypes
 #endif
 
+-- MonadUtils of GHC 7.6 or earlier defines its own MonadIO.
+-- RWST does not automatically become an instance of MonadIO.
+-- MonadUtils of GHC 7.8 or later imports MonadIO in Monad.Control.IO.Class.
+-- So, RWST automatically becomes an instance of MonadIO.
+import MonadUtils
+
 #if __GLASGOW_HASKELL__ < 708
+-- To make RWST an instance of MonadIO.
 import Control.Monad.Trans.Class (lift)
 import Data.Monoid (Monoid)
 #endif