Crate iter_utils 

iter-utils

Iterator utilities for infinite sequences, lazy creation, and termination.

Features

• Perpetuity: A trait for infinite sequences where next_item() returns T directly (no Option).
• delay: Lazy iterator creation for recursive patterns (e.g., Fibonacci).
• stop_once: Like take_while, but includes the terminal item.

Usage

use iter_utils::{Perpetuity, delay, Stopper};

// Infinite sequences without .unwrap()
let mut ids = 1..;
let id = ids.next_item(); // Returns i32, not Option<i32>

// Lazy recursive iterators
fn fibs() -> Box<dyn Iterator<Item = u32>> {
    Box::new([0, 1].into_iter()
        .chain(delay(fibs).zip(delay(fibs).skip(1)).map(|(a, b)| a + b)))
}

// Inclusive termination
let items: Vec<_> = (1..10).stop_once(|&x| x == 5).collect();
// [1, 2, 3, 4, 5] - includes the 5

Structs

Delayed

StopOnce

Successors

Take

Traits

Delay

Lets you call fibs.delay() instead of delay(fibs), if such is your wont.

Perpetuity

Like Iterator, but returns items directly, rather than Options.

Stopper

Functions

assimilate

Returns the specified Perpetuity, erasing any further type information.

delay

Wraps an iterator created by new on the first call to next().