Safe Haskell	Safe
Language	Haskell2010

Control.Monad.Trans.Lift.Catch

Description

Lifting the catch operation.

Synopsis

Documentation

class MonadTrans t => LiftCatch t where Source #

The class of monad transformers capable of lifting catch.

Minimal complete definition

liftCatch

Methods

liftCatch :: Monad m => Catch e m (StT t a) -> Catch e (t m) a Source #

Lift the catch operation. Should satisfy the uniformity property

lift (cf m f) = liftCatch (lift . cf) (lift f)

Instances

LiftCatch MaybeT Source #
Methods liftCatch :: Monad m => Catch * e m (StT MaybeT a) -> Catch * e (MaybeT m) a Source #
LiftCatch ListT Source #
Methods liftCatch :: Monad m => Catch * e m (StT ListT a) -> Catch * e (ListT m) a Source #
Monoid w => LiftCatch (WriterT w) Source #
Methods liftCatch :: Monad m => Catch * e m (StT (WriterT w) a) -> Catch * e (WriterT w m) a Source #
Monoid w => LiftCatch (WriterT w) Source #
Methods liftCatch :: Monad m => Catch * e m (StT (WriterT w) a) -> Catch * e (WriterT w m) a Source #
LiftCatch (StateT s) Source #
Methods liftCatch :: Monad m => Catch * e m (StT (StateT s) a) -> Catch * e (StateT s m) a Source #
LiftCatch (StateT s) Source #
Methods liftCatch :: Monad m => Catch * e m (StT (StateT s) a) -> Catch * e (StateT s m) a Source #
LiftCatch (IdentityT *) Source #
Methods liftCatch :: Monad m => Catch * e m (StT (IdentityT ) a) -> Catch e (IdentityT * m) a Source #
LiftCatch (ExceptT e) Source #
Methods liftCatch :: Monad m => Catch * e m (StT (ExceptT e) a) -> Catch * e (ExceptT e m) a Source #
Monoid w => LiftCatch (WriterT w) Source #
Methods liftCatch :: Monad m => Catch * e m (StT (WriterT w) a) -> Catch * e (WriterT w m) a Source #
LiftCatch (ReaderT * r) Source #
Methods liftCatch :: Monad m => Catch * e m (StT (ReaderT * r) a) -> Catch * e (ReaderT * r m) a Source #
Monoid w => LiftCatch (RWST r w s) Source #
Methods liftCatch :: Monad m => Catch * e m (StT (RWST r w s) a) -> Catch * e (RWST r w s m) a Source #
Monoid w => LiftCatch (RWST r w s) Source #
Methods liftCatch :: Monad m => Catch * e m (StT (RWST r w s) a) -> Catch * e (RWST r w s m) a Source #
Monoid w => LiftCatch (RWST r w s) Source #
Methods liftCatch :: Monad m => Catch * e m (StT (RWST r w s) a) -> Catch * e (RWST r w s m) a Source #

type Catch k e m a = m a -> (e -> m a) -> m a #

Signature of the catchE operation, introduced in Control.Monad.Trans.Except. Any lifting function liftCatch should satisfy

lift (cf m f) = liftCatch (lift . cf) (lift f)

defaultLiftCatch Source #

Arguments

:: (Monad m, LiftCatch n)
=> (forall x. n m x -> t m x)	Monad constructor
-> (forall o x. t o x -> n o x)	Monad deconstructor
-> Catch e m (StT n a)
-> Catch e (t m) a

Default definition for the liftCatch method.

module Control.Monad.Trans.Class