Safe Haskell	Safe-Inferred
Language	Haskell98

Data.Monoid.State

Synopsis

newtype T s a = Cons {
- run :: s -> (a, s)
}
pure :: a -> T s a
evaluate :: s -> T s a -> a
execute :: s -> T s a -> s
put :: Monoid a => s -> T s a
modify :: Monoid a => (s -> s) -> T s a
mapFst :: (a -> c) -> (a, b) -> (c, b)

Documentation

newtype T s a Source #

This resembles the pure State monad. However, State in transformers is a StateT and mtl is not Haskell 98.

I hope I have the more natural parameter order for evaluate in contrast to mtl and transformers. However, it is different from the parameter order of run.

Could also be written as Monoid.Applicative (Monad.Trans.State s) a.

Constructors

Cons
Fields run :: s -> (a, s)

Instances

Instances details

Functor (T s) Source #
Instance details Defined in Data.Monoid.State Methods fmap :: (a -> b) -> T s a -> T s b (<$) :: a -> T s b -> T s a
C (T s) Source #
Instance details Defined in Data.Monoid.State Methods lift :: Monoid m => m -> T s m Source #
Monoid a => Monoid (T s a) Source #
Instance details Defined in Data.Monoid.State Methods mempty :: T s a mappend :: T s a -> T s a -> T s a mconcat :: [T s a] -> T s a
Semigroup a => Semigroup (T s a) Source #
Instance details Defined in Data.Monoid.State Methods (<>) :: T s a -> T s a -> T s a sconcat :: NonEmpty (T s a) -> T s a stimes :: Integral b => b -> T s a -> T s a

pure :: a -> T s a Source #

evaluate :: s -> T s a -> a Source #

execute :: s -> T s a -> s Source #

put :: Monoid a => s -> T s a Source #

modify :: Monoid a => (s -> s) -> T s a Source #

mapFst :: (a -> c) -> (a, b) -> (c, b) Source #