Safe Haskell	Safe-Inferred
Language	GHC2021

Conduit.App.Monad

Synopsis

newtype AppM a = AppM {
- runAppM :: ReaderT Env IO a
}
class Monad m => MonadApp m where
- liftApp :: AppM a -> m a
runService :: FeatureError e => AppM (Either e a) -> ActionT AppM a

Documentation

newtype AppM a Source #

The app monad. woo.

Constructors

AppM
Fields runAppM :: ReaderT Env IO a

Instances

Instances details

MonadIO AppM Source #
Instance details Defined in Conduit.App.Monad Methods liftIO :: IO a -> AppM a #
Applicative AppM Source #
Instance details Defined in Conduit.App.Monad Methods pure :: a -> AppM a # (<>) :: AppM (a -> b) -> AppM a -> AppM b # liftA2 :: (a -> b -> c) -> AppM a -> AppM b -> AppM c # (>) :: AppM a -> AppM b -> AppM b # (<*) :: AppM a -> AppM b -> AppM a #
Functor AppM Source #
Instance details Defined in Conduit.App.Monad Methods fmap :: (a -> b) -> AppM a -> AppM b # (<$) :: a -> AppM b -> AppM a #
Monad AppM Source #
Instance details Defined in Conduit.App.Monad Methods (>>=) :: AppM a -> (a -> AppM b) -> AppM b # (>>) :: AppM a -> AppM b -> AppM b # return :: a -> AppM a #
MonadApp AppM Source #
Instance details Defined in Conduit.App.Monad Methods liftApp :: AppM a -> AppM a Source #
MonadUnliftIO AppM Source #
Instance details Defined in Conduit.App.Monad Methods withRunInIO :: ((forall a. AppM a -> IO a) -> IO b) -> AppM b #
MonadReader Env AppM Source #
Instance details Defined in Conduit.App.Monad Methods ask :: AppM Env # local :: (Env -> Env) -> AppM a -> AppM a # reader :: (Env -> a) -> AppM a #
MonadApp (ActionT AppM) Source #
Instance details Defined in Conduit.App.Monad Methods liftApp :: AppM a -> ActionT AppM a Source #

class Monad m => MonadApp m where Source #

Lifts computations to the app monad level. (MonadApp m) shouldn't be used directly as a constraint; Rather, just use liftApp and see Has.

Methods

liftApp :: AppM a -> m a Source #

Instances

Instances details

MonadApp AppM Source #
Instance details Defined in Conduit.App.Monad Methods liftApp :: AppM a -> AppM a Source #
MonadApp (ActionT AppM) Source #
Instance details Defined in Conduit.App.Monad Methods liftApp :: AppM a -> ActionT AppM a Source #

runService :: FeatureError e => AppM (Either e a) -> ActionT AppM a Source #

Runs a service in the App monad and converts its potentially failed result to the appropriate error if neccesary.

data MyErr = Aw Text
data MyResult = Yay Text deriving (Generic, ToJSON)

instance FeatureError MyErr where
  handleFeatureError (ResultErr msg) = do 
    status status500
    text msg

endpoint = get "/" $ do
  (result :: MyResult) <- runService (someAppService :: AppM (Either MyErr MyResult))
  json result