Control.Monad.Supervisor.Session

Documentation

onNothing :: Monad m => m (Maybe b) -> m b -> m b

type SessionData = Map TypeRep Dynamic

Set user-defined data in the context of the session.

The data is indexed by type in a map. So the user can insert-retrieve different kinds of data in the session context to add different behaviours to the supervisor monad.

emptySessionData :: Map k a

setSessionData :: (MonadState SessionData m, Typeable a) => a -> m ()

delSessionData :: (MonadState SessionData m, Typeable a) => a -> m ()

getSessionData :: (Typeable a, MonadState SessionData m) => m (Maybe a)

Get the session data of the desired type if there is any.

runs :: b -> StateT b IO a -> IO a

main :: IO ()