Struct State 

pub struct State<S, A> { /* private fields */ }

A State monad: transforms state S into (A, S).

Implementations

impl<S: 'static, A: 'static> State<S, A>

pub fn new(f: impl FnOnce(S) -> (A, S) + 'static) -> Self

Create a State from a state transformation function.

pub fn pure(a: A) -> Self

where A: Clone,

Lift a pure value into the State monad.

pub fn bind<B: 'static>( self, f: impl FnOnce(A) -> State<S, B> + 'static, ) -> State<S, B>

Monadic bind.

pub fn map<B: 'static>(self, f: impl FnOnce(A) -> B + 'static) -> State<S, B>

Map over the result value.

pub fn run(self, initial: S) -> (A, S)

Run the state computation with an initial state.

pub fn eval(self, initial: S) -> A

Run and return only the value.

pub fn exec(self, initial: S) -> S

Run and return only the final state.

pub fn get() -> State<S, S>

where S: Clone,

Read the current state.

pub fn put(new_s: S) -> State<S, ()>

where S: 'static,

Set a new state.

pub fn modify(f: impl FnOnce(S) -> S + 'static) -> State<S, ()>

Modify the state with a function.