diff options
Diffstat (limited to 'compiler/utils/Exception.hs')
| -rw-r--r-- | compiler/utils/Exception.hs | 24 |
1 files changed, 4 insertions, 20 deletions
diff --git a/compiler/utils/Exception.hs b/compiler/utils/Exception.hs index b4908997a8..850393e359 100644 --- a/compiler/utils/Exception.hs +++ b/compiler/utils/Exception.hs @@ -21,11 +21,11 @@ tryIO = try -- | A monad that can catch exceptions. A minimal definition -- requires a definition of 'gcatch'. -- --- Implementations on top of 'IO' should implement 'gblock' and 'gunblock' to --- eventually call the primitives 'Control.Exception.block' and --- 'Control.Exception.unblock' respectively. These are used for +-- Implementations on top of 'IO' should implement 'gmask' to +-- eventually call the primitive 'Control.Exception.mask'. +-- These are used for -- implementations that support asynchronous exceptions. The default --- implementations of 'gbracket' and 'gfinally' use 'gblock' and 'gunblock' +-- implementations of 'gbracket' and 'gfinally' use 'gmask' -- thus rarely require overriding. -- class MonadIO m => ExceptionMonad m where @@ -46,20 +46,6 @@ class MonadIO m => ExceptionMonad m where -- exception handling monad instead of just 'IO'. gfinally :: m a -> m b -> m a - -- | DEPRECATED, here for backwards compatibilty. Instances can - -- define either 'gmask', or both 'block' and 'unblock'. - gblock :: m a -> m a - -- | DEPRECATED, here for backwards compatibilty Instances can - -- define either 'gmask', or both 'block' and 'unblock'. - gunblock :: m a -> m a - -- XXX we're keeping these two methods for the time being because we - -- have to interact with Haskeline's MonadException class which - -- still has block/unblock; see GhciMonad.hs. - - gmask f = gblock (f gunblock) - gblock f = gmask (\_ -> f) - gunblock f = f -- XXX wrong; better override this if you need it - gbracket before after thing = gmask $ \restore -> do a <- before @@ -76,8 +62,6 @@ class MonadIO m => ExceptionMonad m where instance ExceptionMonad IO where gcatch = Control.Exception.catch gmask f = mask (\x -> f x) - gblock = block - gunblock = unblock gtry :: (ExceptionMonad m, Exception e) => m a -> m (Either e a) gtry act = gcatch (act >>= \a -> return (Right a)) |