vrd 0.0.10

A lightweight, no_std-friendly random number generator backed by Xoshiro256++ with optional Mersenne Twister support.
Documentation 
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// Copyright © 2023-2026 vrd. All rights reserved.
// SPDX-License-Identifier: Apache-2.0 OR MIT

//! Fisher-Yates shuffle in place.
//!
//! Run: `cargo run --example shuffle`

#[path = "support.rs"]
mod support;

use vrd::Random;

fn main() {
    support::header("vrd -- shuffle");

    support::task_with_output(
        "shuffle reorders without dropping elements",
        || {
            let mut rng = Random::from_u64_seed(7);
            let mut deck: Vec<u32> = (1..=10).collect();
            let original: Vec<_> = deck.to_vec();
            rng.shuffle(&mut deck);
            let mut sorted = deck.clone();
            sorted.sort_unstable();
            vec![
                format!("original = {original:?}"),
                format!("shuffled = {deck:?}"),
                format!("multiset preserved = {}", sorted == original),
            ]
        },
    );

    support::task_with_output("Same seed -> same shuffle", || {
        let mut a = Random::from_u64_seed(42);
        let mut b = Random::from_u64_seed(42);
        let mut da: Vec<u32> = (1..=8).collect();
        let mut db: Vec<u32> = (1..=8).collect();
        a.shuffle(&mut da);
        b.shuffle(&mut db);
        vec![
            format!("a = {da:?}"),
            format!("b = {db:?}"),
            format!("equal = {}", da == db),
        ]
    });

    support::summary(2);
}