Struct Reader 

pub struct Reader<E, A> { /* private fields */ }

A Reader monad: a computation that depends on an environment E.

Wraps a function E -> A.

Implementations

impl<E: Clone + 'static, A: 'static> Reader<E, A>

pub fn new(f: impl Fn(E) -> A + 'static) -> Self

Create a reader from a function.

pub fn run_reader(self, env: E) -> A

Run the reader with the given environment.

pub fn map<B: 'static>(self, f: impl Fn(A) -> B + 'static) -> Reader<E, B>

Map a function over the result.

pub fn pure(a: A) -> Self

where A: Clone,

Create a reader that ignores its environment and returns a.