Safe Haskell	None
Language	GHC2021

GHC.Utils.Monad.State.Strict

Contents

Description

A state monad which is strict in its state.

Synopsis

newtype State s a where
- State' (s -> (# a, s #))
- pattern State :: (s -> (# a, s #)) -> State s a
state :: (s -> (a, s)) -> State s a
evalState :: State s a -> s -> a
execState :: State s a -> s -> s
runState :: State s a -> s -> (a, s)
get :: State s s
gets :: (s -> a) -> State s a
put :: s -> State s ()
modify :: (s -> s) -> State s ()

The State monad

newtype State s a Source #

A state monad which is strict in the state s, but lazy in the value a.

See Note [Strict State monad] for the particular notion of strictness and implementation details.

Constructors

State' (s -> (# a, s #))

Bundled Patterns

pattern State :: (s -> (# a, s #)) -> State s a

Instances details

Applicative (State s) Source #
Instance details Defined in GHC.Utils.Monad.State.Strict Methods pure :: a -> State s a # (<>) :: State s (a -> b) -> State s a -> State s b # liftA2 :: (a -> b -> c) -> State s a -> State s b -> State s c # (>) :: State s a -> State s b -> State s b # (<*) :: State s a -> State s b -> State s a #
Functor (State s) Source #
Instance details Defined in GHC.Utils.Monad.State.Strict Methods fmap :: (a -> b) -> State s a -> State s b # (<$) :: a -> State s b -> State s a #
Monad (State s) Source #
Instance details Defined in GHC.Utils.Monad.State.Strict Methods (>>=) :: State s a -> (a -> State s b) -> State s b # (>>) :: State s a -> State s b -> State s b # return :: a -> State s a #

state :: (s -> (a, s)) -> State s a Source #

runState :: State s a -> s -> (a, s) Source #

Operations

gets :: (s -> a) -> State s a Source #

put :: s -> State s () Source #

modify :: (s -> s) -> State s () Source #