CountNonZero

Overview

The CountNonZeroExt crate provides an extension trait for Rust's standard Iterator trait, enabling the counting of non-zero elements in iterators in a way that returns an Option<NonZeroUsize>. This approach optimally integrates with Rust's type system to offer a compile-time guarantee that the result, when present, is indeed non-zero. This functionality is particularly useful in scenarios where distinguishing between zero and non-zero counts is critical and can lead to more efficient code by leveraging the NonZeroUsize type's ability to optimize memory layouts and conditional logic.

Features

Extends the Iterator trait with the count_non_zero method. The count_non_zero method counts the elements for which the iterator yields values, returning an Option<NonZeroUsize>.

Usage

use std::num::NonZeroUsize;

use count_non_zero_ext::CountNonZeroExt;

fn main() {
    let data = vec![1, 2, 0, 4];
    let count = data.into_iter().filter(|el| el % 2 == 0).count_non_zero();
    
    match count {
        Some(non_zero_count) => println!("Non-zero count of elements: {}", non_zero_count),
        None => println!("Iterator is empty"),
    }
}