Serokell.Util.Lens

Extra operators on Lens

Documentation

(%%=) :: Lens' s a -> State a b -> State s b infix 4

Similar to %= operator, but takes State action instead of (a -> a)

(%?=) :: Lens' s a -> ExceptT t (State a) b -> ExceptT t (State s) b infix 4

Like %%= but with possiblity of failure

class Monad m => WrappedM m where

Similar to Wrapped, but for Monads.

Associated Types

type UnwrappedM m :: * -> *

Methods

_WrappedM :: Iso' (m a) (UnwrappedM m a)

packM :: m a -> UnwrappedM m a

unpackM :: UnwrappedM m a -> m a

Instances

Monad m => WrappedM (LoggerNameBox m)

Associated Types

type UnwrappedM (LoggerNameBox m :: * -> *) :: * -> *

Methods

_WrappedM :: (Profunctor p, Functor f) => p (UnwrappedM (LoggerNameBox m) a) (f (UnwrappedM (LoggerNameBox m) a)) -> p (LoggerNameBox m a) (f (LoggerNameBox m a))

packM :: LoggerNameBox m a -> UnwrappedM (LoggerNameBox m) a

unpackM :: UnwrappedM (LoggerNameBox m) a -> LoggerNameBox m a

_UnwrappedM :: WrappedM m => Iso' (UnwrappedM m a) (m a)

zoom' :: MonadState s m => LensLike' (Zoomed (State s) a) s t -> StateT t Identity a -> m a

A zoom which works in arbitrary MonadState.

See https://github.com/ekmett/lens/issues/580. You might be surprised but actual zoom doesn't work in any MonadState, it only works in a handful of state monads and their combinations defined by Zoom.

magnify' :: MonadReader s m => LensLike' (Magnified (Reader s) a) s t -> ReaderT t Identity a -> m a

A magnify which works in arbitrary MonadReader.

listL :: (IsList (t a), IsList (t b)) => Iso (t a) (t b) [Item (t a)] [Item (t b)]

This isomorphism can be used to convert to or from an instance of IsList.

Note that this function is quite general but doesn't allow to switch container - in most cases such behavious eliminates need in specifing container type manually.