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

//! `Random` implements `rand_core::TryRng` (with `Error = Infallible`),
//! so the blanket-implemented `Rng` trait works on it too.
//!
//! Run: `cargo run --example traits`

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

use rand::rand_core::{Rng, TryRng};
use vrd::Random;

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

    support::task_with_output(
        "Rng methods (next_u32, next_u64, fill_bytes)",
        || {
            let mut rng = Random::from_u64_seed(1);
            let u32_v = rng.next_u32();
            let u64_v = rng.next_u64();
            let mut buf = [0u8; 8];
            rng.fill_bytes(&mut buf);
            vec![
                format!("next_u32  = {u32_v}"),
                format!("next_u64  = {u64_v}"),
                format!("fill_bytes = {buf:02x?}"),
            ]
        },
    );

    support::task_with_output(
        "TryRng methods (try_next_u32, try_fill_bytes)",
        || {
            let mut rng = Random::from_u64_seed(1);
            let v = rng.try_next_u32().expect("Infallible");
            let mut buf = [0u8; 8];
            rng.try_fill_bytes(&mut buf).expect("Infallible");
            vec![
                format!("try_next_u32 = {v}"),
                format!("try_fill_bytes -> {buf:02x?}"),
            ]
        },
    );

    support::task_with_output(
        "SeedableRng plugs Random into the wider rand ecosystem",
        || {
            let seed = [9u8; 32];
            let mut rng = Random::from_seed(seed);
            vec![format!(
                "from_seed(seed[..32]) -> first u32 = {}",
                rng.next_u32()
            )]
        },
    );

    support::summary(3);
}