planet-mitchell-0.0.0: Planet Mitchell

Safe HaskellSafe
LanguageHaskell2010

Monad.Fix

Synopsis

Documentation

class Monad m => MonadFix (m :: * -> *) where #

Monads having fixed points with a 'knot-tying' semantics. Instances of MonadFix should satisfy the following laws:

purity
mfix (return . h) = return (fix h)
left shrinking (or tightening)
mfix (\x -> a >>= \y -> f x y) = a >>= \y -> mfix (\x -> f x y)
sliding
mfix (liftM h . f) = liftM h (mfix (f . h)), for strict h.
nesting
mfix (\x -> mfix (\y -> f x y)) = mfix (\x -> f x x)

This class is used in the translation of the recursive do notation supported by GHC and Hugs.

Minimal complete definition

mfix

Methods

mfix :: (a -> m a) -> m a #

The fixed point of a monadic computation. mfix f executes the action f only once, with the eventual output fed back as the input. Hence f should not be strict, for then mfix f would diverge.

Instances
MonadFix []

Since: base-2.1

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> [a]) -> [a] #

MonadFix Maybe

Since: base-2.1

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> Maybe a) -> Maybe a #

MonadFix IO

Since: base-2.1

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> IO a) -> IO a #

MonadFix Par1

Since: base-4.9.0.0

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> Par1 a) -> Par1 a #

MonadFix Min

Since: base-4.9.0.0

Instance details

Defined in Data.Semigroup

Methods

mfix :: (a -> Min a) -> Min a #

MonadFix Max

Since: base-4.9.0.0

Instance details

Defined in Data.Semigroup

Methods

mfix :: (a -> Max a) -> Max a #

MonadFix First

Since: base-4.9.0.0

Instance details

Defined in Data.Semigroup

Methods

mfix :: (a -> First a) -> First a #

MonadFix Last

Since: base-4.9.0.0

Instance details

Defined in Data.Semigroup

Methods

mfix :: (a -> Last a) -> Last a #

MonadFix Option

Since: base-4.9.0.0

Instance details

Defined in Data.Semigroup

Methods

mfix :: (a -> Option a) -> Option a #

MonadFix Identity

Since: base-4.8.0.0

Instance details

Defined in Data.Functor.Identity

Methods

mfix :: (a -> Identity a) -> Identity a #

MonadFix First

Since: base-4.8.0.0

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> First a) -> First a #

MonadFix Last

Since: base-4.8.0.0

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> Last a) -> Last a #

MonadFix Dual

Since: base-4.8.0.0

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> Dual a) -> Dual a #

MonadFix Sum

Since: base-4.8.0.0

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> Sum a) -> Sum a #

MonadFix Product

Since: base-4.8.0.0

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> Product a) -> Product a #

MonadFix NonEmpty

Since: base-4.9.0.0

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> NonEmpty a) -> NonEmpty a #

MonadFix Tree

Since: containers-0.5.11

Instance details

Defined in Data.Tree

Methods

mfix :: (a -> Tree a) -> Tree a #

MonadFix Seq

Since: containers-0.5.11

Instance details

Defined in Data.Sequence.Internal

Methods

mfix :: (a -> Seq a) -> Seq a #

MonadFix Eval 
Instance details

Defined in Control.Parallel.Strategies

Methods

mfix :: (a -> Eval a) -> Eval a #

MonadFix SmallArray 
Instance details

Defined in Data.Primitive.SmallArray

Methods

mfix :: (a -> SmallArray a) -> SmallArray a #

MonadFix Array 
Instance details

Defined in Data.Primitive.Array

Methods

mfix :: (a -> Array a) -> Array a #

MonadFix Moment 
Instance details

Defined in Reactive.Banana.Types

Methods

mfix :: (a -> Moment a) -> Moment a #

MonadFix MomentIO 
Instance details

Defined in Reactive.Banana.Types

Methods

mfix :: (a -> MomentIO a) -> MomentIO a #

MonadFix Element 
Instance details

Defined in Control.Concurrent.Chan.Unagi.NoBlocking.Types

Methods

mfix :: (a -> Element a) -> Element a #

MonadFix (Either e)

Since: base-4.3.0.0

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> Either e a) -> Either e a #

MonadFix (ST s)

Since: base-2.1

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> ST s a) -> ST s a #

MonadFix (Grammar r) 
Instance details

Defined in Text.Earley.Grammar

Methods

mfix :: (a -> Grammar r a) -> Grammar r a #

MonadFix m => MonadFix (MaybeT m) 
Instance details

Defined in Control.Monad.Trans.Maybe

Methods

mfix :: (a -> MaybeT m a) -> MaybeT m a #

Functor f => MonadFix (Free f) 
Instance details

Defined in Control.Monad.Free

Methods

mfix :: (a -> Free f a) -> Free f a #

MonadFix m => MonadFix (Yoneda m) 
Instance details

Defined in Data.Functor.Yoneda

Methods

mfix :: (a -> Yoneda m a) -> Yoneda m a #

MonadFix f => MonadFix (Rec1 f)

Since: base-4.9.0.0

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> Rec1 f a) -> Rec1 f a #

MonadFix f => MonadFix (Alt f)

Since: base-4.8.0.0

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> Alt f a) -> Alt f a #

MonadFix m => MonadFix (IdentityT m) 
Instance details

Defined in Control.Monad.Trans.Identity

Methods

mfix :: (a -> IdentityT m a) -> IdentityT m a #

MonadFix m => MonadFix (ExceptT e m) 
Instance details

Defined in Control.Monad.Trans.Except

Methods

mfix :: (a -> ExceptT e m a) -> ExceptT e m a #

(MonadFix m, Error e) => MonadFix (ErrorT e m) 
Instance details

Defined in Control.Monad.Trans.Error

Methods

mfix :: (a -> ErrorT e m a) -> ErrorT e m a #

MonadFix (Indexed i a) 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

mfix :: (a0 -> Indexed i a a0) -> Indexed i a a0 #

MonadFix m => MonadFix (StateT s m) 
Instance details

Defined in Control.Monad.Trans.State.Lazy

Methods

mfix :: (a -> StateT s m a) -> StateT s m a #

MonadFix (STE e s) 
Instance details

Defined in Control.Monad.STE.Internal

Methods

mfix :: (a -> STE e s a) -> STE e s a #

MonadFix m => MonadFix (StateT s m) 
Instance details

Defined in Control.Monad.Trans.State.Strict

Methods

mfix :: (a -> StateT s m a) -> StateT s m a #

MonadFix m => MonadFix (WriterT w m) 
Instance details

Defined in Control.Monad.Trans.Writer.CPS.Internal

Methods

mfix :: (a -> WriterT w m a) -> WriterT w m a #

MonadFix ((->) r :: * -> *)

Since: base-2.1

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> r -> a) -> r -> a #

(MonadFix f, MonadFix g) => MonadFix (f :*: g)

Since: base-4.9.0.0

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> (f :*: g) a) -> (f :*: g) a #

(MonadFix f, MonadFix g) => MonadFix (Product f g)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Product

Methods

mfix :: (a -> Product f g a) -> Product f g a #

MonadFix m => MonadFix (ReaderT r m) 
Instance details

Defined in Control.Monad.Trans.Reader

Methods

mfix :: (a -> ReaderT r m a) -> ReaderT r m a #

(Stream s, MonadFix m) => MonadFix (ParsecT e s m)

Since: megaparsec-6.0.0

Instance details

Defined in Text.Megaparsec.Internal

Methods

mfix :: (a -> ParsecT e s m a) -> ParsecT e s m a #

MonadFix f => MonadFix (M1 i c f)

Since: base-4.9.0.0

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> M1 i c f a) -> M1 i c f a #