diff options
Diffstat (limited to 'compiler/main/GhcMonad.hs')
| -rw-r--r-- | compiler/main/GhcMonad.hs | 11 |
1 files changed, 3 insertions, 8 deletions
diff --git a/compiler/main/GhcMonad.hs b/compiler/main/GhcMonad.hs index f72cacc7ef..846744c439 100644 --- a/compiler/main/GhcMonad.hs +++ b/compiler/main/GhcMonad.hs @@ -1,4 +1,4 @@ -{-# LANGUAGE CPP, RankNTypes #-} +{-# LANGUAGE CPP, DeriveFunctor, RankNTypes #-} {-# OPTIONS_GHC -funbox-strict-fields #-} -- ----------------------------------------------------------------------------- -- @@ -90,7 +90,7 @@ logWarnings warns = do -- | A minimal implementation of a 'GhcMonad'. If you need a custom monad, -- e.g., to maintain additional state consider wrapping this monad or using -- 'GhcT'. -newtype Ghc a = Ghc { unGhc :: Session -> IO a } +newtype Ghc a = Ghc { unGhc :: Session -> IO a } deriving (Functor) -- | The Session is a handle to the complete state of a compilation -- session. A compilation session consists of a set of modules @@ -98,9 +98,6 @@ newtype Ghc a = Ghc { unGhc :: Session -> IO a } -- interactive evaluation, and various caches. data Session = Session !(IORef HscEnv) -instance Functor Ghc where - fmap f m = Ghc $ \s -> f `fmap` unGhc m s - instance Applicative Ghc where pure a = Ghc $ \_ -> return a g <*> m = do f <- g; a <- m; return (f a) @@ -158,13 +155,11 @@ reifyGhc act = Ghc $ act -- -- Note that the wrapped monad must support IO and handling of exceptions. newtype GhcT m a = GhcT { unGhcT :: Session -> m a } + deriving (Functor) liftGhcT :: m a -> GhcT m a liftGhcT m = GhcT $ \_ -> m -instance Functor m => Functor (GhcT m) where - fmap f m = GhcT $ \s -> f `fmap` unGhcT m s - instance Applicative m => Applicative (GhcT m) where pure x = GhcT $ \_ -> pure x g <*> m = GhcT $ \s -> unGhcT g s <*> unGhcT m s |