Safe Haskell	Safe
Language	Haskell2010

FreeC.Monad.Class.Hoistable

Description

This module defines type classes for converting between monads and their monad transformer counterparts.

Synopsis

class MonadTrans t => Hoistable t where
- hoist :: Monad m => t Identity a -> t m a
class Hoistable t => UnHoistable t where
- unhoist :: Monad m => t m a -> m (t Identity a)
hoistMaybe :: Monad m => Maybe a -> MaybeT m a

Documentation

Type class for monad transformers whose inner monad can be lifted from Identity to some arbitrary Monad.

Methods

Lifts the transformed identity monad to any transformed monad.

Instances

Hoistable ReporterT Source #	The reporter monad can be lifted to any reporter transformer.
Instance details Defined in FreeC.Monad.Reporter Methods hoist :: Monad m => ReporterT Identity a -> ReporterT m a Source #
Hoistable ConverterT Source #	The converter monad can be lifted to any converter transformer.
Instance details Defined in FreeC.Monad.Converter Methods hoist :: Monad m => ConverterT Identity a -> ConverterT m a Source #

Type class for Hoistable types whose hoist method can be undone.

Methods

unhoist :: Monad m => t m a -> m (t Identity a) Source #

Undoes hoist.

Instances

UnHoistable ReporterT Source #	`hoist` can be undone for reporters.
Instance details Defined in FreeC.Monad.Reporter Methods unhoist :: Monad m => ReporterT m a -> m (ReporterT Identity a) Source #

Lifts a Maybe value to an arbitrary monad.

Since Maybe and MaybeT Identity are distinct types, no equivalent Hoistable instance can be specified.