monad-extras 0.5.1 → 0.5.2

raw patch · 2 files changed

+33/−2 lines, 2 filesdep +mmorphdep +transformers-base

Dependencies added: mmorph, transformers-base

Files

• Control/Monad/Extra.hs +30/−1
• monad-extras.cabal +3/−1

@@ -1,10 +1,16 @@ {-# LANGUAGE FlexibleContexts #-}+{-# LANGUAGE GeneralizedNewtypeDeriving #-}+{-# LANGUAGE KindSignatures #-}+{-# LANGUAGE MultiParamTypeClasses #-}+{-# LANGUAGE TypeFamilies #-}  module Control.Monad.Extra where  import Control.Applicative import Control.Monad+import Control.Monad.Base import Control.Monad.IO.Class+import Control.Monad.Morph import Control.Monad.Trans.Cont import Control.Monad.Trans.Control import Data.IORef@@ -172,7 +178,7 @@         readIORef result  -- | Draw monadic actions from a list until one of them yields a value---   satisfying the predicate, and then return all the values up to and +--   satisfying the predicate, and then return all the values up to and --   including the first that succeeds in a list within that monad. sequenceUntil :: Monad m => (a -> Bool) -> [m a] -> m [a] sequenceUntil _ [] = return []@@ -183,3 +189,26 @@         else do             as <- sequenceUntil p ms             return (a:as)++-- | A type wrapper for composing monad transformers.  This is very similar to+--   'Data.Functor.Compose', just one level up.+newtype ComposeT (f :: (* -> *) -> * -> *) (g :: (* -> *) -> * -> *) m a+    = ComposeT { getComposeT :: f (g m) a }+    deriving (Functor, Applicative, Monad, MonadIO)++instance (MFunctor f, MonadTrans f, MonadTrans g)+         => MonadTrans (ComposeT f g) where+    lift = ComposeT . hoist lift . lift++instance (MonadIO (f (g m)), Applicative (f (g m)))+         => MonadBase IO (ComposeT f g m) where+    liftBase = liftIO++instance (Applicative (f (g m)), MonadBaseControl IO (f (g m)),+          MonadIO (f (g m)))+         => MonadBaseControl IO (ComposeT f g m) where+    newtype StM (ComposeT f g m) a = StMComposeT (StM (f (g m)) a)+    liftBaseWith f =+        ComposeT $ liftBaseWith $ \runInBase -> f $ \k ->+            liftM StMComposeT $ runInBase $ getComposeT k+    restoreM (StMComposeT m) = ComposeT . restoreM $ m

@@ -1,5 +1,5 @@ name:           monad-extras-version:        0.5.1+version:        0.5.2 synopsis:       Extra utility functions for working with monads -- description: homepage:       http://github.com/jwiegley/monad-extras@@ -18,5 +18,7 @@         Control.Monad.Extra     build-depends:         base >= 4 && < 5+      , mmorph       , monad-control       , transformers+      , transformers-base