From 7619e4e9dd88c152d1e00b6fea073c3d52dc797f Mon Sep 17 00:00:00 2001
From: Michael Snoyman <michael@snoyman.com>
Date: Mon, 5 Dec 2011 10:04:33 +0200
Subject: [PATCH] monad-control 0.3

---
 yesod-core/Yesod/Widget.hs  | 28 +++++++++++++++++++++++++++-
 yesod-core/yesod-core.cabal |  3 ++-
 2 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/yesod-core/Yesod/Widget.hs b/yesod-core/Yesod/Widget.hs
index ead6e285..a47d58cd 100644
--- a/yesod-core/Yesod/Widget.hs
+++ b/yesod-core/Yesod/Widget.hs
@@ -5,6 +5,7 @@
 {-# LANGUAGE MultiParamTypeClasses #-}
 {-# LANGUAGE TypeSynonymInstances #-}
 {-# LANGUAGE UndecidableInstances #-}
+{-# LANGUAGE CPP #-}
 -- | Widgets combine HTML with JS and CSS dependencies with a unique identifier
 -- generator, allowing you to create truly modular HTML components.
 module Yesod.Widget
@@ -78,16 +79,41 @@ import qualified Data.Map as Map
 import Language.Haskell.TH.Quote (QuasiQuoter)
 import Language.Haskell.TH.Syntax (Q, Exp (InfixE, VarE, LamE), Pat (VarP), newName)
 
+#if MIN_VERSION_monad_control(0, 3, 0)
+import Control.Monad.Trans.Control (MonadTransControl (..), MonadBaseControl (..), defaultLiftBaseWith, defaultRestoreM, ComposeSt)
+#else
 import Control.Monad.IO.Control (MonadControlIO)
+#endif
 import qualified Text.Hamlet as NP
 import Data.Text.Lazy.Builder (fromLazyText)
 import Text.Blaze (toHtml, preEscapedLazyText)
+import Control.Monad.Base (MonadBase (liftBase))
 
 -- | A generic widget, allowing specification of both the subsite and master
 -- site datatypes. This is basically a large 'WriterT' stack keeping track of
 -- dependencies along with a 'StateT' to track unique identifiers.
 newtype GGWidget m monad a = GWidget { unGWidget :: GWInner m monad a }
-    deriving (Functor, Applicative, Monad, MonadIO, MonadControlIO)
+    deriving (Functor, Applicative, Monad, MonadIO
+#if !MIN_VERSION_monad_control(0, 3, 0)
+    , MonadControlIO
+#endif
+    )
+
+instance MonadBase b m => MonadBase b (GGWidget master m) where
+    liftBase = lift . liftBase
+#if MIN_VERSION_monad_control(0, 3, 0)
+instance MonadTransControl (GGWidget master) where
+    newtype StT (GGWidget master) a = StRWS {unStRWS :: (a, Int, GWData (Route master))}
+    liftWith f = GWidget $ RWST $ \r s -> liftM (\x -> (x, s, mempty))
+                                     (f $ \t -> liftM StRWS $ runRWST (unGWidget t) r s)
+    restoreT mSt = GWidget $ RWST $ \_ _ -> liftM unStRWS mSt
+    {-# INLINE liftWith #-}
+    {-# INLINE restoreT #-}
+instance MonadBaseControl b m => MonadBaseControl b (GGWidget master m) where
+     newtype StM (GGWidget master m) a = StMT {unStMT :: ComposeSt (GGWidget master) m a}
+     liftBaseWith = defaultLiftBaseWith StMT
+     restoreM     = defaultRestoreM   unStMT
+#endif
 
 instance MonadTrans (GGWidget m) where
     lift = GWidget . lift
diff --git a/yesod-core/yesod-core.cabal b/yesod-core/yesod-core.cabal
index a79c4099..d42b5a9a 100644
--- a/yesod-core/yesod-core.cabal
+++ b/yesod-core/yesod-core.cabal
@@ -64,7 +64,8 @@ library
                    , old-locale            >= 1.0.0.2  && < 1.1
                    , failure               >= 0.1      && < 0.2
                    , containers            >= 0.2      && < 0.5
-                   , monad-control         >= 0.2      && < 0.3
+                   , monad-control         >= 0.2      && < 0.4
+                   , transformers-base     >= 0.4
                    , enumerator            >= 0.4.8    && < 0.5
                    , cookie                >= 0.3      && < 0.4
                    , blaze-html            >= 0.4.1.3  && < 0.5