Safe Haskell | None |
---|---|
Language | Haskell2010 |
MonadState without the function dependency m -> s
.
- module Control.Monad.Trans.Reader
- class Monad m => MonadReaders r m where
- askPoly :: m r
- localPoly :: (r -> r) -> m a -> m a
- readerPoly :: (r -> a) -> m a
- viewPoly :: forall r m a. MonadReaders r m => Getting a r a -> m a
Documentation
module Control.Monad.Trans.Reader
class Monad m => MonadReaders r m where Source
localPoly :: (r -> r) -> m a -> m a Source
:: (r -> a) | The selector function to apply to the environment. |
-> m a |
Retrieves a function of the current environment.
MonadReaders r m => MonadReaders r (MaybeT m) Source | |
MonadReaders r m => MonadReaders r (ListT m) Source | |
MonadReaders r m => MonadReaders r (IdentityT m) Source | |
MonadReaders r ((->) r) Source | |
(Monoid w, MonadReaders r m) => MonadReaders r (WriterT w m) Source | |
(Monoid w, MonadReaders r m) => MonadReaders r (WriterT w m) Source | |
MonadReaders r m => MonadReaders r (StateT s m) Source | |
MonadReaders r m => MonadReaders r (StateT s m) Source | |
MonadReaders r m => MonadReaders r (ExceptT e m) Source | |
(Error e, MonadReaders r m) => MonadReaders r (ErrorT e m) Source | |
MonadReaders r' m => MonadReaders r' (ContT r m) Source | Modiifed copies of instances from mtl. |
Monad m => MonadReaders r (ReaderT r m) Source | |
(Monad m, Monoid w) => MonadReaders r (RWST r w s m) Source | |
(Monad m, Monoid w) => MonadReaders r (RWST r w s m) Source |
viewPoly :: forall r m a. MonadReaders r m => Getting a r a -> m a Source
Modified view function that works if there is a MonadReaders r instance