Struct RecursiveStep 

pub struct RecursiveStep;

A builder that converts a two-argument accumulator-style recursion into a trampolined computation.

// factorial via recursive step
let result = RecursiveStep::run(10u64, 1u64, |n, acc| {
    if n == 0 { None } else { Some((n - 1, n * acc)) }
});
assert_eq!(result, 3628800);

Implementations

impl RecursiveStep

pub fn run<I, A, F>(initial: I, acc: A, step: F) -> A

where I: Clone + 'static, A: Clone + 'static, F: Fn(I, A) -> Option<(I, A)> + Clone + 'static,

Run the accumulator loop.

• initial: the initial input value.
• acc: the initial accumulator.
• step: given (input, acc), returns Some((next_input, next_acc)) to continue, or None to stop and return acc.