An iterator adapter that allows you to efficiently peek the nth item of an iterator.
Itermediate values are memoized and heap allocations are avoided when possible.
First, add peek-nth to the dependencies section of your Cargo.toml:
[dependencies]
peek-nth = "0.2"Next, add the following snippet to the entry point of your crate (lib.rs or main.rs):
extern crate peek_nth;extern crate peek_nth;
use peek_nth::IteratorExt;
fn main() {
let mut iter = "Hello, world!".chars().peekable_nth();
assert_eq!(iter.peek_nth(4), Some(&'o')); // Cache Miss
assert_eq!(iter.peek_nth(3), Some(&'l')); // Cache Hit
assert_eq!(iter.peek_nth(2), Some(&'l')); // Cache Hit
assert_eq!(iter.peek_nth(1), Some(&'e')); // Cache Hit
assert_eq!(iter.peek_nth(0), Some(&'H')); // Cache Hit
assert_eq!(iter.peek_nth(7), Some(&'w')); // Cache Miss
assert_eq!(iter.collect::<String>(), "Hello, world!");
}Licensed under either of
- Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
- MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)
at your option.
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.