Merge branch 'joeyconfig'

1 files changed, 16 insertions, 0 deletions

diff --git a/Propellor/Exception.hs b/Propellor/Exception.hs
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+{-# LANGUAGE PackageImports #-}
+
+module Propellor.Exception where
+
+import qualified "MonadCatchIO-transformers" Control.Monad.CatchIO as M
+import Control.Exception
+import Control.Applicative
+
+import Propellor.Types
+
+-- | Catches IO exceptions and returns FailedChange.
+catchPropellor :: Propellor Result -> Propellor Result
+catchPropellor a = either (\_ -> FailedChange) id <$> tryPropellor a
+
+tryPropellor :: Propellor a -> Propellor (Either IOException a)
+tryPropellor = M.try