clean up some ugly code

This commit is contained in:
Joey Hess 2013-09-27 19:52:36 -04:00
parent d6883dcd7f
commit c6032b0dab
5 changed files with 40 additions and 24 deletions

View file

@ -14,6 +14,7 @@ import qualified Control.Exception as E
import Control.Applicative
import Control.Monad
import System.IO.Error (isDoesNotExistError)
import Utility.Data
{- Catches IO errors and returns a Bool -}
catchBoolIO :: IO Bool -> IO Bool
@ -54,5 +55,5 @@ tryNonAsync a = (Right <$> a) `catchNonAsync` (return . Left)
{- Catches only DoesNotExist exceptions, and lets all others through. -}
tryWhenExists :: IO a -> IO (Maybe a)
tryWhenExists a = either (const Nothing) Just <$>
tryWhenExists a = eitherToMaybe <$>
tryJust (guard . isDoesNotExistError) a