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{-# LANGUAGE ExistentialQuantification #-}
module Web.Scotty.Exceptions (
Handler(..)
-- * catching
, catch
, catchAny
, catches
, catchesOptionally
-- * trying
, try
, tryAny
) where
import Data.Maybe (maybeToList)
import UnliftIO (MonadUnliftIO(..), catch, catchAny, catches, try, tryAny, Handler(..))
-- | Handlers are tried sequentially
catchesOptionally :: MonadUnliftIO m =>
m a
-> Maybe (Handler m a) -- ^ if present, this 'Handler' is tried first
-> [Handler m a] -- ^ these are tried in order
-> m a
catchesOptionally io mh handlers = io `catches` (maybeToList mh <> handlers)
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